Agilent N8932A Users Guide N89000 Series Power Supplies

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Keysight N8900 Series Autoranging System DC Power Supply

Operating and Service Guide

1 Preliminary Information 5

Documentation and Firmware Revisions 5 Contacting Keysight Technologies 5

Legal and Safety Information 6

Legal Notices 6 Safety Symbols 8 Safety Notices 9

Models and Options 12

Model Ratings 12 Accsssories/Options 12

Specifications and Characteristics 13

Specifications 13 Supplemental Characteristics 5 kW 15 Supplemental Characteristics 10 kW 16 Supplemental Characteristics 15 kW 17 Common Characteristics 18 Autoranging Characteristics 19 Dimension Diagrams 20

2 Operating Information 21

Introduction to the Instrument 22

Front Panel at a Glance 23 Front Panel Display at a Glance 23 Front Panel Keys at a Glance 24 Rear Panel at a Glance 25

Front Panel Menu 26 Installing the Instrument 28

Before Installation or Use 29 AC Mains Connections 31 Single Unit Connections 35 Multiple Unit Connections 42 External Control Signal Connections (Analog) 46 Interface Connections 47

Getting Started 50

Turn the Unit On 50 Set the Output Voltage 50 Set the Output Current 51 Set the Over-Voltage Protection 52 Enable the Output 54 Use the Built-in Help System 54

Remote Interface Configuration 55

USB Configuration 55 GPIB Configuration 55 LAN Configuration 56 Modifying the LAN Settings 57 Using the Web Interface 59 Using Telnet 60

2 Keysight N8900 Series Operating and Service Guide

Using Sockets 61 Interface Lockout 61

Using the Power Supply 62

Programming the Output 63 Programming Output Protection 64 Programming Output Steps 66 MakingMeasurements 69 Parallel Operation 70 External Control Signal Programming 73 System-Related Operations 81 Operating Mode Tutorial 83 SAS Operation 85

3 SCPI Programming Reference 91

Related Information 92 Introduction to the SCPI Language 93

Command Types 93 Keywords 94 Queries 94 Command Separators and Terminators 94 Syntax Conventions 95 Parameter Types 96 Device Clear 97

Commands by Subsystem 98

Subsystem 98 Common Commands 98 Additional Commands 98 Calibrate Commands 99 Current Commands 102 Digital Commands 104 Display/LXI Commands 105 Measure Commands 106 Output Commands 107 Solar Array Simulator Commands 109 Status Commands 114 System Commands 121 Trigger Commands 127 Voltage Commands 129 Status Tutorial 130

Command Quick Reference 135

ABORt Command 135 CALibrate Commands 135 CURRent Commands 135 DIGital Command 136 DISPlay Command 136 IEEE-488 Commands 136 INITiate Commands 136 LXI Command 137

Keysight N8900 Series Operating and Service Guide 3

MEASure Commands 137 MEMory Commands 137 OUTPut Commands 137 SASimulator Commands 138 STATus Commands 138 SYSTem Commands 139 TRIGger Commands 139 VOLTage Commands 139

Reset State (*RST) 140 SCPI Error Messages 142 Compatibility Commands 148

Channel Parameter 148 Code Compatible Commands 148

4 Service and Maintenance 149

Introduction 150

Types of Service Available 150 Before Returning the Unit 150 Repackaging for Shipment 150

Verification and Calibration 151

Verification 151 Calibration Interval 151 Test Considerations 151 Measurement Techniques 152 Recommended Test Equipment and Setups 153 Performance Verification 155 Calibration Procedure 160 Test Record Forms 165

Self-Test Procedure 180

Power-On Self-Test 180 User-Initiated Self-Test 180

Firmware Update 181

Software Required 181 Update Procedure 181 Restricting Access 181

Instrument Sanitize 182 Calibration Switches 183

Accessing the Calibration Switch 183 Switch Functions 183

Disassembly 185

Electrostatic Discharge (ESD) Precautions 185 Cover Removal 185

Manual Backdating 187

Output Terminal Isolation 187 Analog Control Operation 187 SAS Operation 188

Index 189

4 Keysight N8900 Series Operating and Service Guide

Keysight N8900 Series Operating and Service Guide

1 Preliminary Information

Legal and Safety Information

Models and Options

Specifications and Characteristics

This document includes user, service, and programming information for the Keysight N8900 Series Autoranging System DC Power Supply.

Documentation and Firmware Revisions

You can download the latest version of this document at

www.keysight.com/find/n8900-doc. The latest version is also available for

mobile devices at www.keysight.com/find/n8900-mobilehelp. If you have feedback on this document, please contact Keysight at

www.keysight.com/find/n8900-docfeedback.

For the latest firmware revision go to Firmware Updates.

Contacting Keysight Technologies

Use www.keysight.com/find/assist for information on contacting Keysight worldwide, or contact your Keysight Technologies representative.

1 Preliminary Information

Legal and Safety Information

Legal Notices

Safety Symbols

Safety Notices

Legal Notices

No part of this manual may be reproduced in any form or by any means (including electronic storage and retrieval or translation into a foreign language) without prior agreement and written consent from Keysight Technologies Inc. as governed by United States and international copyright laws.

Manual Part Number

Manual part number N8900-90901

Edition

Edition 6, updated December 2017

Published By

Keysight Technologies 550 Clark Drive, Suite 101 Budd Lake, New Jersey 07828 USA

Warranty

The material contained in this document is provided "as is," and is subject to being changed, without notice, in future editions. Further, to the maximum extent permitted by applicable law, Keysight disclaims all warranties, either express or implied, with regard to this manual and any information contained herein, including but not limited to the implied warranties of merchantability and fitness for a particular purpose. Keysight shall not be liable for errors or for incidental or consequential damages in connection with the furnishing, use, or performance of this document or of any information contained herein. Should Keysight and the user have a separate written agreement with warranty terms covering the material in this document that conflict with these terms, the warranty terms in the separate agreement shall control.

6 Keysight N8900 Series Operating and Service Guide

1 Preliminary Information

U.S. Government Rights

The Software is “commercial computer software,” as defined by Federal Acquisition Regulation (“FAR”) 2.101. Pursuant to FAR 12.212 and 27.405-3 and Department of Defense FAR Supplement (“DFARS”) 227.7202, the U.S. government acquires commercial computer software under the same terms by which the software is customarily provided to the public. Accordingly, Keysight provides the Software to U.S. government customers under its standard commercial license, which is embodied in its End User License Agreement (EULA), a copy of which can be found at http://www.keysight.com/find/sweula. The license set forth in the EULA represents the exclusive authority by which the U.S. government may use, modify, distribute, or disclose the Software. The EULA and the license set forth therein, does not require or permit, among other things, that Keysight: (1) Furnish technical information related to commercial computer software or commercial computer software documentation that is not customarily provided to the public; or (2) Relinquish to, or otherwise provide, the government rights in excess of these rights customarily provided to the public to use, modify, reproduce, release, perform, display, or disclose commercial computer software or commercial computer software documentation. No additional government requirements beyond those set forth in the EULA shall apply, except to the extent that those terms, rights, or licenses are explicitly required from all providers of commercial computer software pursuant to the FAR and the DFARS and are set forth specifically in writing elsewhere in the EULA. Keysight shall be under no obligation to update, revise or otherwise modify the Software. With respect to any technical data as defined by FAR 2.101, pursuant to FAR 12.211 and 27.404.2 and DFARS 227.7102, the U.S. government acquires no greater than Limited Rights as defined in FAR 27.401 or DFAR 227.7103-5 (c), as applicable in any technical data

Declaration of Conformity

Declarations of Conformity for this product and for other Keysight products may be downloaded from the Web. Go to http://www.keysight.com/go/conformity and click on “Declarations of Conformity.” You can then search by product number to find the latest Declaration of Conformity.

Waste Electrical and Electronic Equipment (WEEE) Directive 2002/96/EC

This product complies with the WEEE Directive 2002/96/EC marketing requirement. The affixed product label (see below) indicates that you must not discard this electrical/electronic product in domestic household waste.

Product Category: With reference to the equipment types in the WEEE directive Annex 1, this product is classified as “Monitoring and Control instrumentation” product.

Do not dispose in domestic household waste.

To return unwanted products, contact our local Keysight office, or see http://www.keysight.com/environment/product for more information.

Keysight N8900 Series Operating and Service Guide 7

1 Preliminary Information

Safety Symbols

A WARNING notice denotes a hazard. It calls attention to an operating procedure, practice, or the like that, if not correctly performed or adhered to, could result in personal injury or DEATH. Do not proceed beyond a WARNING notice until the indicated conditions are fully understood and met.

A CAUTION notice denotes a hazard. It calls attention to an operating procedure, practice, or the like that, if not correctly performed or adhered to, could result in damage to the product or loss of important data. Do not proceed beyond a CAUTION notice until the indicated conditions are fully understood and met.

Direct current

Alternating current

Frame or chassis terminal

Standby supply. Unit is not completely disconnected from AC mains when switch is off.

Caution, risk of electric shock

Caution, refer to accompanying documents

Earth ground terminal

The CE mark is a registered trademark of the European Community.

The TUV mark is a registered trademark of the European community.

The C-tick mark is a registered trademark of the Spectrum Management Agency of Australia. This signifies compliance with the Australian EMC Framework regulations under the terms of the Radio Communications Act of 1992.

South Korean Class A EMC Declaration This equipment is Class A suitable for professional use and is for use in electromagnetic environments outside of the home.

Contains one or more of the 6 hazardous substances above the maximum concentration value (MCV), 40 Year EPUP.

8 Keysight N8900 Series Operating and Service Guide

1 Preliminary Information

ISM1-A This text indicates that the instrument is an Industrial Scientific and Medical Group 1 Class A

product (CISPER 11, Clause 4).

ICES/NMB-001 This text indicates product compliance with the Canadian Interference- Causing Equipment Stand-

ard (ICES-001).

Safety Notices

The following general safety precautions must be observed during all phases of operation of this instrument. Failure to comply with these precautions or with specific warnings or instructions elsewhere in this manual violates safety standards of design, manufacture, and intended use of the instrument. Keysight Technologies assumes no liability of the customer’s failure to comply with the requirements.

The equipment is for industrial use. It is not applicable for IT mains supply systems. Equipment operators are subject to all applicable safety regulations. Along with the warning and safety notices in this manual, all relevant safety, accident prevention, and environmental regulations must also be followed. In particular, the operators of the equipment:

l Must be informed of the relevant safety requirements.

l Must have read and understood the operating manual before using the equipment.

l Must use the designated and recommended safety equipment.

General Do not use this product in any manner not specified by the manufacturer. The protective features of this product may be impaired if it is used in a manner not specified in the operating instructions. Only operate the product at the rated mains voltage and phase as stipulated on the input label.

Environmental Conditions Never use the instrument outside of the specified environmental conditions described under Common Characteristics.

Ground the Instrument This product is provided with protective earth terminals. To minimize shock hazard, the instrument must be connected to the AC mains through a grounded power cable, with the ground wire firmly connected to an electrical ground (safety ground) at the power outlet. Any interruption of the protective (grounding) conductor or disconnection of the protective earth terminal will cause a potential shock hazard that could result in injury or death.

Keysight N8900 Series Operating and Service Guide 9

1 Preliminary Information

Before Applying Power Verify that all safety precautions are taken. All rear panel connections must be made with the unit turned off, and must be performed by qualified personnel who are aware of the hazards involved. Improper actions can cause fatal injury as well as equipment damage. Note the instrument's external markings described under "Safety Symbols".

HAZARDOUSVOLTAGES All models generate voltages above 60 VDC, with some models rated at up to 1,500 VDC! Ensure that all instrument connections, load wiring, and load connections are insulated or covered -so that no accidental contact with lethal voltages can occur.

SHOCK HAZARD Turn off AC power before making rear panel connections. Ensure that any residual voltages present at the + and -output terminals are discharged before touching the output terminals. To fully discharge the output terminals, momentarily connect a DVM rated at 1,000 VDC between the + output terminal and ground. Repeat this procedure for the – output terminal. Do not use this DVM on units that are powered ON with voltages >1000 VDC.

EQUIPMENTDAMAGE and SHOCK HAZARD Do not connect anything other than the Sharing wires from other units to the Sharing inputs. Do not connect or disconnect wires when the unit is on or damage may occur. The Sharing connections are not for voltage sensing. Voltages greater than 18 VDC will permanently damage the Sharing inputs. Damaged Sharing inputs cause unknown voltages at the output terminals that may exceed hazardous levels.

External Voltage Sources Do not connect voltage sources to the output of the power supply with voltage ratings that are greater than the nominal voltage rating of the supply. Under no circumstances can you connect an external voltage with reversed polarity to the output terminal. Equipment damage will result.

Do Not Operate in an Explosive Atmosphere Do not operate the instrument in the presence of flammable gases or fumes.

Do Not Remove the Instrument Cover Only qualified, service-trained personnel who are aware of the hazards involved should remove instrument covers. Always disconnect the power cable and any external circuits before removing the instrument cover.

10 Keysight N8900 Series Operating and Service Guide

1 Preliminary Information

Do Not Modify the Instrument Do not install substitute parts or perform any unauthorized modification to the product. Return the product to a Keysight Sales and Service Office for service and repair to ensure that safety features are maintained.

Fuses The instrument contains internal fuses, which are not customer accessible.

Cleaning To prevent electric shock, disconnect the AC mains before cleaning. Clean the outside of the instrument with a soft, lint-free, slightly damp cloth. Do not use detergent. Disassembly is not required or recommended for cleaning.

In Case of Damage Instruments that are not functioning correctly, appear damaged or defective should be made inoperative and secured against unintended operation until they can be repaired by qualified service personnel.

Keysight N8900 Series Operating and Service Guide 11

1 Preliminary Information

Models and Options

Model Ratings

5 kW Models Voltage Current AC mains

Keysight N8920A Keysight N8921A Keysight N8923A Keysight N8924A

Keysight N8940A Keysight N8941A Keysight N8943A Keysight N8944A

10 kW Models Voltage Current AC mains

Keysight N8925A Keysight N8926A Keysight N8928A Keysight N8929A Keysight N8930A

Keysight N8945A Keysight N8946A Keysight N8948A Keysight N8949A Keysight N8950A

80 V 200 V 500 V 750 V

1000 V

80 V 200 V 500 V 750 V

1000 V

170 A

70 A 30 A 20 A

170 A

70 A 30 A 20 A

340 A 140 A

60 A 40 A 30 A

340 A 140 A

60 A 40 A 30 A

208 VAC 208 VAC 208 VAC 208 VAC

400 VAC 400 VAC 400 VAC 400 VAC

208 VAC 208 VAC 208 VAC 208 VAC 208 VAC

400 VAC 400 VAC 400 VAC 400 VAC 400 VAC

15 kW Models Voltage Current AC mains

Keysight N8931A Keysight N8932A Keysight N8934A Keysight N8935A

Keysight N8937A,

Keysight N8937APV

Keysight N8951A Keysight N8952A Keysight N8954A Keysight N8955A

Keysight N8957A,

Keysight N8957APV

80 V 200 V 500 V 750 V

1500 V 1500 V

80 V 200 V 500 V 750 V

1500 V 1500 V

Accsssories/Options

Accessory/Option Number Description

Keysight N8958A SAS Curve Generator software

Rack Mount Kit for all models N8937APV/N8957APV only: www.keysight.com/find/N8900APVsoftware

510 A 210 A

90 A 60 A 30 A 30 A

510 A 210 A

90 A 60 A 30 A 30 A

208 VAC 208 VAC 208 VAC 208 VAC 208 VAC 208 VAC

400 VAC 400 VAC 400 VAC 400 VAC 400 VAC 400 VAC

12 Keysight N8900 Series Operating and Service Guide

1 Preliminary Information

Specifications and Characteristics

Specifications

Supplemental Characteristics

CommonCharacteristics

Autoranging Characteristics

DimensionDiagrams

Unless otherwise noted, specifications are warranted over the ambient temperature range of 0°C to 45°C after a 30-minute warm-up period. Specifications apply from >2% to 100% of the rated voltage and from >1% to 100% of the rated current, measured at the output terminals with local sensing (sense terminals not connected).

Supplemental characteristics are not warranted but are descriptions of performance determined either by design or by type testing. All supplemental characteristics are typical unless otherwise noted.

Specifications and characteristics are subject to change without notice.

Specifications

Specification 5 kW N8920A/

N8940A

DC Ratings Voltage: Current: Power:

Output ripple & noise CV rms: CV peak-to-peak:

Load regulation Voltage: Current:

Voltage programming & measurement accuracy

Current programming & measurement accuracy

0 - 80 V

0 - 170 A

5 kW

16 mV

200 mV

40 mV

255 mA

≤ 80 mV ≤ 200 mV ≤ 500 mV ≤ 750 mV

≤ 340 mA ≤ 140 mA ≤ 60 mA ≤ 40 mA

N8921A/

N8941A

0 - 200 V

0 - 70 A

5 kW

40 mV

375 mV/300 mV

100 mV 105 mA

N8923A/

N8943A

0 - 500 V

0 - 30 A

5 kW

70 mV

350 mV

250 mV

45 mA

N8924A/

N8944A

0 - 750 V

0 - 20 A

5 kW

200 mV 800 mV

375 mV

30 mA

Transient response Recovery Time: Settling band:

From 20 Hz to 300 kHz for rms noise; from 20 Hz to 20 MHz for peak-to-peak noise

Accuracy specifications are warranted at 23°C ±5°C

Time to recover to within the settling band following aload change from 10% to 90% of full load

≤ 1.5 ms

0.8 V

≤ 1.5 ms

2 V

≤ 1.5 ms

5 V

≤ 1.5 ms

7.5 V

Keysight N8900 Series Operating and Service Guide 13

1 Preliminary Information

Specification 10 kW N8925A/

N8945A

DC Ratings Voltage: Current: Power:

Output ripple & noise CV rms: CV peak-to-peak:

Load regulation Voltage: Current:

Voltage programming & measurement accuracy

Current programming & measurement accuracy

Transient response Recovery Time: Settling band:

0 - 80 V

0 - 340 A

10 kW

25 mV

320 mV

40 mV

510 mA

≤ 80 mV ≤ 200 mV ≤ 500 mV ≤ 750 mV ≤ 1 V

≤ 680 mA ≤ 280 mA ≤ 120 mA ≤ 80 mA ≤ 60 mA

≤ 1.5 ms

0.8 V

N8926A/

N8946A

0 - 200 V 0 - 140 A

10 kW

40 mV

375 mV/300 mV

100 mV 210 mA

≤ 1.5 ms

2 V

N8928A/

N8948A

0 - 500 V

0 - 60 A

10 kW

70 mV

350 mV

250 mV

90 mA

≤ 1.5 ms

5 V

N8929A/

N8949A

0 - 750 V

0 - 40 A

10 kW

200 mV 800 mV

375 mV

60 mA

≤ 1.5 ms

7.5 V

N8930A/

N8950A

0 - 1000 V

0 - 30 A

10 kW

350 mV

1600 mV

500 mV

53 mA/45 mA

≤ 1.5 ms

10 V

Specification 15 kW N8931A/

N8951A

DC Ratings Voltage: Current: Power:

Output ripple & noise CV rms: CV peak-to-peak:

Load regulation Voltage: Current:

Voltage programming & measurement accuracy

Current programming & measurement accuracy

Transient response Recovery Time: Settling band:

0 - 80 V

0 - 510 A

15 kW

25 mV

320 mV

40 mV

765 mA

≤ 80 mV ≤ 200 mV ≤ 500 mV ≤ 750 mV ≤ 1.5 V

≤ 1.1 A ≤ 420 mA ≤ 180 mA ≤ 120 mA ≤ 60 mA

≤ 1.5 ms

0.8 V

N8932A/

N8952A

0 - 200 V 0 - 210 A

15 kW

40 mV

375 mV/300 mV

100 mV 315 mA

≤ 1.5 ms

2 V

N8934A/

N8954A

0 - 500 V

0 - 90 A

15 kW

70 mV

350 mV

250 mV 135 mA

≤ 1.5 ms

5 V

N8935A/

N8955A

0 - 750 V

0 - 60 A

15 kW

200 mV 800 mV

375 mV

90 mA

≤ 1.5 ms

7.5 V

N8937A/

N8937APV

N8957A/

N8957APV

0 - 1500 V

0 - 30 A

15 kW

400 mV

2400 mV

750 mV

53 mA/45 mA

≤ 1.5 ms

15 V

From 20 Hz to 300 kHz for rms noise; from 20 Hz to 20 MHz for peak-to-peak noise

Accuracy specifications are warranted at 23°C ±5°C

Time to recover to within the settling band following aload change from 10% to 90% of full load

14 Keysight N8900 Series Operating and Service Guide

Supplemental Characteristics 5 kW

1 Preliminary Information

Characteristic 5 kW N8920A/

N8940A

Voltage programming range Current programming range

Programming and Measurement Resolution Voltage: Current:

Temperature Coefficient Voltage: Current:

Output response time Up, full load: Down, full load: Down, no load:

Over-voltage protect range 0 to 88 V 0 to 220 V 0 to 550 V 0 to 825 V

Remote sense compensation per load lead

Source regulation Voltage: Current:

0 to 81.6 V

0 to 173.4 A

4 mV 7 mA

4 mV

8.5 mA

≤ 30 ms ≤ 80 ms

≤ 30 s

2 V 5 V 10 V 18 V

16 mV 85 mA

N8921A/

N8941A

0 to 204 V

0 to 71.4 A

9 mV 3 mA

10 mV

3.5 mA

≤ 30 ms ≤ 80 ms

≤10 s

40 mV 35 mA

N8923A/

N8943A

0 to 510 V

0 to 30.6 A

21 mV

2 mA

25 mV

1.5 mA

≤ 30 ms ≤ 80 ms

≤10 s

100 mV

15 mA

N8924A/

N8944A

0 to 765 V

0 to 20.4 A

31 mV

1 mA

37.5 mV 1 mA

≤ 30 ms ≤ 80 ms

≤10 s

150 mV

10 mA

CC rms ripple & noise 80 mA 22 mA 16 mA 16 mA

OutputTerminal Isolation Positive Terminal: Negative Terminal:

AC Input Nominal Rating: Input Range: Frequency: Phase: Input Current: Max. Inrush Current: Power Factor: Efficiency:

Weight ≤18.5 kg (41 lbs) / ≤17 kg (38 lbs)

Per °C, at rated voltage andcurrent

From 10% to 90% or from 90% to 10% of total voltageexcursion

+/-10% of nominal ACinput rating

Refer to Manual Updates for additional information

Version 2

+ 400 V ± 400 V

87.5%/91.5% 90%/91.5% 91%/93.5% 88%/90%

Version 2

+ 600 V ± 400 V

208/220/230/240 VAC or 400 VAC

± 10 % of nominal rating

45 - 65 Hz

3-phase

L2, L3 - 32 A / L2, L3 - 16 A

41 A / 28 A

> 0.99 at nominal input and rated power

Version 2 + 1000 V

± 725 V

Version 2 + 1000 V

± 725 V

Keysight N8900 Series Operating and Service Guide 15

1 Preliminary Information

Supplemental Characteristics 10 kW

Characteristic 10 kW N8925A/

N8945A

Voltage programming range Current programming range

Programming and Measurement Resolution Voltage: Current:

Temperature Coefficient Voltage: Current:

Output response time Up, full load: Down, full load: Down, no load:

Over-voltage protect range 0 to 88 V 0 to 220 V 0 to 550 V 0 to 825 V 0 - 1100 V

Remote sense compensation per load lead

Source regulation Voltage: Current:

0 to 81.6 V

0 to 346.8 A

4 mV

14 mA

4 mV

17 mA

≤ 30 ms ≤ 80 ms

≤ 30 s / 40 s

2 V 5 V 10 V 18 V 22 V

16 mV

170 mA

N8926A/

N8946A

0 to 204 V

0 to 142.8 A

9 mV 6 mA

10 mV

7 mA

≤ 30 ms ≤ 80 ms

≤10 s

40 mV 70 mA

N8928A/

N8948A

0 to 510 V

0 to 61.2 A

21 mV

3 mA

25 mV

3 mA

≤ 30 ms ≤ 80 ms

≤10 s

100 mV

30 mA

N8929A/

N8949A

0 to 765 V

0 to 40.8 A

31 mV

2 mA

37.5 mV 2 mA

≤ 30 ms ≤ 80 ms

≤10 s

150 mV

20 mA

N8930A/

N8950A

0 to 1020 V

0 to 30.6 A

41 mV

2 mA

50 mV

1.5 mA

≤ 30 ms ≤ 80 ms

≤10 s

200 mV

15 mA

CC rms ripple & noise 160 mA 44 mA 32 mA 32 mA 22 mA

OutputTerminal Isolation Positive Terminal: Negative Terminal:

Weight ≤ 27 kg (60 lbs) / ≤ 25.5 kg (55 lbs)

Per °C, at rated voltage andcurrent

From 10% to 90% or from 90% to 10% of total voltageexcursion

+/-10% of nominal ACinput rating

Refer to Manual Updates for additional information

Version 2

+ 400 V ± 400 V

87.5%/89.5% 89.5%/91.5% 91%/91% 88%/90% 91%/93.5%

Version 2

+ 600 V ± 400 V

208/220/230/240 VAC or 400 VAC

± 10 % of nominal rating

L1 - 56 A; L2, L3 - 32 A / L1 - 28 A; L2, L3 - 16 A

> 0.99 at nominal input and rated power

Version 2 + 1000 V

± 725 V

45 - 65 Hz

3-phase

97 A / 49 A

Version 2 + 1000 V

± 725 V

Version 2 + 1000 V

± 725 V

16 Keysight N8900 Series Operating and Service Guide

Supplemental Characteristics 15 kW

1 Preliminary Information

Characteristic 15 kW N8931A/

N8951A

Voltage programming range Current programming range

Programming and Measurement Resolution Voltage: Current:

Temperature Coefficient Voltage: Current:

Output response time Up, full load: Down, full load: Down, no load:

Over-voltage protect range 0 to 88 V 0 to 220 V 0 to 550 V 0 to 825 V 0 - 1650 V

Remote sense compensation per load lead

Source regulation Voltage: Current:

0 to 81.6 V

0 to 520.2 A

4 mV

21 mA

4 mV

25.5 mA

≤ 30 ms ≤ 80 ms

≤ 30 s

2 V 5 V 10 V 18 V 30 V

16 mV

255 mA

N8932A/

N8952A

0 to 204 V

0 to 214.2 A

9 mV 9 mA

10 mV

10.5 mA

≤ 30 ms ≤ 80 ms

≤10 s

40 mV

105 mA

N8934A/

N8954A

0 to 510 V

0 to 91.8 A

21 mV

4 mA

25 mV

4.5 mA

≤ 30 ms ≤ 80 ms

≤10 s

100 mV

45 mA

N8935A/

N8955A

0 to 765 V

0 to 61.2 A

31 mV

3 mA

37.5 mV 3 mA

≤ 30 ms ≤ 80 ms

≤10 s

150 mV

30 mA

N8937A/

N8937APV

N8957A/

N8957APV

0 to 1530 V

0 to 30.6 A

61 mV

2 mA

75 mV

1.5 mA

≤ 30 ms ≤ 80 ms

≤10 s

300 mV

15 mA

CC rms ripple & noise 240 mA 66 mA 48 mA 48 mA 26 mA

OutputTerminal Isolation Positive Terminal: Negative Terminal:

Weight ≤ 35.5 kg (78 lbs) / ≤ 32 kg (70 lbs)

Per °C, at rated voltage andcurrent

From 10% to 90% or from 90% to 10% of total voltageexcursion

+/-10% of nominal ACinput rating

Refer to Manual Updates for additional information

Version 2

+ 400 V ± 400 V

87.5%/89.5% 89.5%/91.5% 91%/93.5% 88%/90% 91%/93%

Version 2

+ 600 V ± 400 V

208/220/230/240 VAC or 400 VAC

± 10 % of nominal rating

L1, L2, L3 - 56 A / L1, L2, L3 - 28 A

> 0.99 at nominal input and rated power

Version 2 + 1000 V

± 725 V

45 - 65 Hz

3-phase

97 A / 49 A

Version 2 + 1000 V

± 725 V

Version 3 + 1500 V ± 1000 V

Keysight N8900 Series Operating and Service Guide 17

1 Preliminary Information

Common Characteristics

Characteristic All Models

Command Response Time: < 25 ms

Savable States: 10

Analog Programming Input range: Accuracy: Input impedance:

Computer Interfaces LXI Core 2011: USB: GPIB: Language:

0 to 5 V or 0 to 10 V (selectable) Specified instrument accuracy ±0.2% of rating 150 kΩ (referenced to ground)

10/100 Base-T Ethernet (Sockets, VXI-11 protocol, Web user interface) USB 2.0 (USB-TMC488) GPIB IEEE 488 SCPI - 1993, IEEE 488.2 compliant

Regulatory Compliance: EMC:

Safety:

Environmental Operating environment: Temperature range: Relative humidity: Altitude: Storage temperature:

Acoustic Noise - 5 kW models At maximum fan speed: At idle:

Acoustic Noise - 10 kW models At maximum fan speed: At idle:

Acoustic Noise - 15 kW models At maximum fan speed: At idle:

Complies with European EMC Directive for test and measurement products Complies with Australian standard and carries C-Tick mark This ISM device complies with Canadian ICES-001 Cet appareil ISM est conforme à la norme NMB-001 du Canada

Complies with European Low Voltage Directive and carries the CE-marking. Conforms to US and Canadian safety regulations.

Not applicable for IT mains supply systems

Indoor use, installation category II (for AC input), pollution degree 2 0°C to 45°C 80% or less (non-condensing) Up to 2000 meters

-20°C to 70°C

76 dBA max. for 208 VAC input; 57 dBA max. for 400 VAC input 55 dBA max. for 208 VAC input; 48 dBA max. for 400 VAC input

77 dBA max. for 208 VAC input; 62 dBA max. for 400 VAC input 55 dBA max. for 208 VAC input; 51 dBA max. for 400 VAC input

79 dBA max. for 208 VAC input; 72.6 dBA max. for 400 VAC input 56 dBA max. for 208 VAC input; 52 dBA max. for 400 VAC input

18 Keysight N8900 Series Operating and Service Guide

Autoranging Characteristics

1 Preliminary Information

5 kW

Models

V1 80 V 200 V 500 V 750 V

I1 62.5 A 25 A 10 A 6.667 A

V2 29.4 V 71.43 V 166.67 V 250 V

I2 170 A 70 A 30 A 20 A

10 kW

Models

V1 80 V 200 V 500 V 750 V 1000 V

I1 125 A 50 A 20 A 13.33 A 10 A

V2 29.4 V 71.43 V 166.67 V 250 V 333.33 V

I2 340 A 140 A 60 A 40 A 30 A

15 kW

Models

N8920A N8940A

N8925A N8945A

N8931A N8951A

N8921A N8941A

N8926A N8946A

N8932A N8952A

N8923A N8943A

N8928A N8948A

N8934A N8954A

N8924A N8944A

N8929A N8949A

N8935A N8955A

N8930A N8950A

N8937A

N8937APV

N8957A

N8957APV

V1 80 V 200 V 500 V 750 V 1500 V

I1 187.5 A 75 A 30 A 20 A 10 A

V2 29.4 V 71.43 V 166.67 V 250 V 500 V

I2 510 A 210 A 90 A 60 A 30 A

Keysight N8900 Series Operating and Service Guide 19

1 Preliminary Information

Dimension Diagrams

20 Keysight N8900 Series Operating and Service Guide

Keysight N8900 Series Operating and Service Guide

2 Operating Information

Introduction to the Instrument

Front Panel Menu

Installing the Instrument

Getting Started

Remote Interface Configuration

Using the Power Supply

2 Operating Information

Introduction to the Instrument

Front Panel at a Glance

Front Panel Display at a Glance

Front Panel Keys at a Glance

Rear Panel at a Glance

The Keysight N8900 Series is a family of autoranging system DC power supplies with performance and features that are optimized for automated test systems. They are available in power levels of 5 kW, 10 kW, and 15 kW. Voltage levels range from 80 to 1500 V. Current levels range from 20 to 510 A.

Keysight N8937APV and N8957APV models simulate the output characteristics of a photovoltaic array. This capability lets you quickly and comprehensively test solar inverter maximum power point tracking (MPPT) algorithms and inverter efficiency. The SAS Curve Generator software is a free application that simplifies programming the photovoltaic (PV) models. It is available at

www.keysight.com/find/N8900APVsoftware.

Output and system features that are common to all N8900 Series power supplies are described as follows. Refer to the Models and Options section for a description of the output ratings of the various models.

Output features

l Full programming capability is provided for the entire range of output voltage and current

l Paralleling capability for increased output power

l Protection capability includes over-voltage, over-current, over-temperature, and other protections

l Solar array simulator operation - only applies to N8937APV and N8957APV models

Measurement features

l Voltage, current, and power measurements

l Combined output current of paralleled units

System features

l Save and recall up to 10 instrument states in non-volatile memory

l GPIB (IEEE-488), LAN, and USB remote programming interfaces are built in

l Front panel menu setup for GPIB and LANparameters

l LXI Core 2011 compliant, including a built-in Web server

l SCPI (Standard Commands for Programmable Instruments) compatibility

22 Keysight N8900 Series Operating and Service Guide

Front Panel at a Glance

Front Panel Display at a Glance

2 Operating Information

Output voltage and current Displays the actual output voltage and current.

Connection status A = analog programming is enabled

M = the paralleled unit is configured as the master S = the paralleled unit is configured as a slave

Operating status Indicates one of the following:

OFF = the output is off CV = the output is in constant voltage mode CC = the output is in constant current mode CP = the output is limited by the power limit boundary OV = the output is disabled by the over-voltage protection OC = the output is disabled by the over-current protection OT = the output is disabled by the over-temperature protection INH = the output is disabled by an external control signal PF = the output is disabled because of a low voltage on the AC mains MSP = the output is disabled by the master/slave protection UNR = the output is unregulated

Voltage and Current settings Displays the programmed voltage and current settings.

Keysight N8900 Series Operating and Service Guide 23

2 Operating Information

Interface status Indicates the following remote interface activity:

Err = an error has occurred (press Error key to display error message) Lan = the LAN is connected and has been configured IO = there is activity on one of the remote interfaces

Front Panel Keys at a Glance

The AC line switch turns the unit on or off (off = 0). The indicator above the On/Off switch shows the display status. Green indicates normal operation. Amber indicates that the display is in screen saver mode. It is also on during the boot-up process. Press any key to exit screen saver mode.

The system keys access the following front panel meter and command menus: Meter returns the display to metering mode. Repeatedly press this key to cycle through the following measurement functions: Voltage, Current Voltage, Power Voltage, Current, Power

Menu accesses the command menu. Function key is reserved for future use. Back backs out of a menu without activating any changes. Help accesses information about the displayed menu control. Error displays any error messages in the error queue.

The navigation keys do the following:

Arrows let you move around in the command menus. Select lets you make a selection in the command menus. It also lets

you enter edit mode for editing the numeric parameters.

The output keys do the following:

On/Off enables or disables the output. Voltage lets you change the voltage setting. Current lets you change the current setting.

The numeric entry keys do the following: The 0 through 9 keys enter numbers. The (.) key is the decimal point. The – key is used to enter a minus sign. The up/down arrow keys increment or decrement voltage or current settings.They also select letters in alphabetic entry fields. The E key enters an exponent. Add the value to the right of the E. The back arrow key deletes digits as it backspaces over them. The Enter key enters a value. If you exit a field without pressing the Enter key, the value is ignored.

24 Keysight N8900 Series Operating and Service Guide

Rear Panel at a Glance

2 Operating Information

GPIB GPIB interface connector

LAN LAN interface connector

Sharing Current sharing connections - for parallel operation

+/–Sense Remote sense connections (if not used, local sensing is internally connected)

–Output; +Output Negative and positive output terminals

AC input AC line input

USB USB interface connector

Analog External control signal connector

Master/Slave (Group) Master/slave connectors - for grouping paralleled units

For electrical shock protection, always connect the AC input earth ground terminal.

Keysight N8900 Series Operating and Service Guide 25

2 Operating Information

Front Panel Menu

This is an overview of the front-panel menus. For a brief tutorial, refer to Use the front panel menu.

Press the Menu key to access the front panel menus.

1st Menu

Level

Output Fixed

Transient Mode Selects voltage and current transient modes

Protect OVP Configures over-voltage protection settings

States Reset Resets all instrument settings to the reset (*RST) state

2nd Level 3rd & 4th

Levels

SAS

Mode Selects the operating mode: Fixed, Curve. or Table

Step Programs the voltage and current step settings

OCP Configures over-current protection settings

Clear Clears protection conditions and displays output status

Voltage Programs the output voltage settings

Current Programs the output current settings

Curve

Scale

Description

Programs the SAS curve parameters: Imp, Isc, Vmp, and Voc

Selects a scale factor for the current and voltage curves

SaveRecall Saves and recalls instrument settings

PowerOn Selects the power-on instrument state

System IO LAN Displays LAN commands

Settings View the currently active network settings

Modify Modifies the network configuration

Apply Applies the configuration changes and restarts

Cancel Cancels the configuration changes

Reset Performs an LXI LCI reset of LANsettings and restarts

Defaults Resets the network to the as-shipped defaults and restarts

USB Displays USB identification string

GPIB Display or change the GPIB address

Analog Sets the analog interface amplitude (5 V or 10 V)

Only applies to Models N8737APV and N8957APV.

26 Keysight N8900 Series Operating and Service Guide

2 Operating Information

1st Menu

Level

System Group Function Defines the function of each unit in the paralleled group

2nd Level 3rd & 4th

Levels

Master Displays the configured slave addresses

Slave Specifies the slave address

Preferences Display Configures the screen saver and wake on IO timer

Admin Login/Logout Enter a password to access the Admin functions

Cal Displays calibration commands

Voltage Calibrates voltage programming and measurement

Current Calibrates current programming and measurement

Count View the calibration count

Date View and modify the calibration date

Save Saves the calibration data

IO Enables/disable the LAN, USB, and GPIB

Description

Sanitize Performs NISPOM secure erase of all user data

Update Password protect firmware update

Password Changes the admin password

About Displays model, output ratings, serial number, and firm-

ware

Keysight N8900 Series Operating and Service Guide 27

2 Operating Information

Installing the Instrument

Before Installation or Use

AC Mains Connections

Single Unit Connections

Multiple Unit Connections

External Control Signal Connections (Analog)

Interface Connections

28 Keysight N8900 Series Operating and Service Guide

2 Operating Information

Before Installation or Use

Inspect the Unit

When you receive your power supply, inspect it for any obvious damage that may have occurred during shipment. If there is damage, notify the shipping carrier and nearest Keysight Sales and Support Office immediately. Refer to www.keysight.com/find/assist.

Until you have checked out the power supply, save the shipping carton and packing materials in case the unit has to be returned. Check the list below and verify that you have received these items with your unit. If anything is missing, please contact your nearest Keysight Sales and Support Office.

Check for Items Supplied

Before getting started, check the following list and verify that you have received these items with your unit. If anything is missing, please contact your nearest Keysight Sales and Support Office.

Item Description Part Number

DC covers Safety covers for DC output terminals 5003-2051

Sense cover Safety covers for sense terminals (≥750 V units) 5066-1913

2 position plug Connector plug for Sharing terminals 5003-2038

4 position plug Connector plug for Sense terminals (≤500 V units) 5003-2037

4 position plug Connector plug for Sense terminals (≥750 V units) 0360-3120

AC plug Connector plug for AC input 5003-2053 for 400 VAC inputs

5003-2091 for 208 VAC inputs

Hardware Kit 1-set mounting hardware for low current terminals

1-set mounting hardware for high current terminals

5003-2089 for ≥ 500 VAC outputs 5003-2090 for < 500 VAC outputs

Review Safety Information

This power supply is a Safety Class 1 instrument, which means it has a protective earth terminal. That terminal must be connected to earth ground through a power source equipped with an earth ground. Refer to the Safety Notices section at the beginning of this guide for general safety information. Before installation or operation, check the power supply and review this guide for safety warnings and instructions. Safety warnings for specific procedures are located at appropriate places throughout this guide.

Keysight N8900 Series Operating and Service Guide 29

2 Operating Information

Observe Environmental Conditions

Do not operate the instrument in the presence of flammable gases or fumes.

The environmental conditions of the power supply are documented under Specifications. Basically, the unit should only be operated indoors in a controlled environment. Do not operate the unit in areas where the ambient temperature exceeds +45 degrees Celsius. This applies for rack-mounting as well as for bench use.

Use Caution when Transporting the Unit

Two people are required when handling units. Because of the unit’s weight, do not lift or move it alone. Moving by hand should be avoided where possible. If unavoidable, lift only the instrument’s chassis; do not lift the unit using the exterior handles, knobs, or output terminals.

Provide Adequate Air Flow

Do not block the air intake at the front, or the exhaust at the rear of the unit.

The dimensions of your power supply, an outline diagram, and airflow direction are given under

Dimension Diagrams. Fans cool the power supply by drawing air through the front and exhausting it

out the back. Allows at least 8 inches (20 cm) of space at the front and back of the unit for adequate air circulation.

30 Keysight N8900 Series Operating and Service Guide

AC Mains Connections

AC Mains Phase Distribution

Phase Balancing with Multiple Units

Power Cables

AC Mains Phase Distribution

SHOCK HAZARD The instrument requires a chassis ground connection through a separate conductor. The AC mains must include an earth ground connection.

AC mains connections must be made by a qualified electrician who knows about 3phase mains circuits and all applicable safety standards and requirements.

400 VAC, 3-phase

5 kW units only

2 Operating Information

400 VAC, 3-phase

10 kW units only

400 VAC, 3-phase

15 kW units only

Keysight N8900 Series Operating and Service Guide 31

2 Operating Information

208 VAC, 3-phase

5 kW units only

208 VAC, 3-phase

10 kW units only

208 VAC, 3-phase

15 kW units only

Note that either delta-type or Y-type AC mains distribution can be used, provided that the correct lineto-line voltage is applied.

Phase Balancing with Multiple Units

The previous figures illustrate the phase current distribution. The N8900 power supplies can have from one to three internal 5.6 kW power blocks, each of which is connected across a separate phase of the 3-phase AC mains. For 5 kW and 10 kW units this will result in a current imbalance when installing one or two units. Installing three units will result in a balanced current distribution. For 15 kW units, there is no current imbalance, as all phases draw approximately the same current.

The following figures illustrate how to install three 5 kW units or three 10 kW units in order to obtain a balanced current draw on the 3-phase AC mains.

32 Keysight N8900 Series Operating and Service Guide

2 Operating Information

5 kW, 208 VAC and 400 VAC, phase balancing scheme

10 kW, 208 VAC and 400 VAC, phase balancing scheme

Power Cables

An AC mains power cable is not provided with the unit. Refer to the following table for the maximum current capacity requirements for each cable conductor.

If required by local electrical codes, install a fuse or circuit breaker between the ac mains and the unit. Refer to the following table for current ratings.

Keep the AC mains cables as short as possible. The longer the cable, the greater the voltage loss due to cable resistance.

The cable cross-section must be suitable for the maximum input current of the instrument. The ground cable must have the same cross-section as the phase cable.

Safety agency requirements dictate that there must be a way to physically disconnect the AC mains cable from the unit. A disconnect device, either a switch or circuit breaker must be provided in the final installation. The disconnect device must be close to the equipment, must be easily accessible, and must be marked as the disconnect device for this equipment. It must meet the input ratings requirements listed in the following table.

Unit Rating L1 I

5 kW - 208 Vac NA 32 A 32 A

5 kW - 400 Vac NA 16 A 16 A

10 kW - 208 Vac 56 A 32 A 32 A

10 kW - 400 Vac 28 A 16 A 16 A

max

L2 I

max

L3 I

max

15 kW - 208 Vac 56 A 56 A 56 A

15 kW - 400 Vac 28 A 28 A 28 A

Keysight N8900 Series Operating and Service Guide 33

2 Operating Information

Power Connector

Remove the strain relief to access the connector plug. Connect the AC mains cable to the connector plug as shown in the following illustrations. Insert the cable wires into the connector plug. On 400 VAC connectors, insert a flat blade screwdriver to release the internal wire clamp. On 208 VAC connectors, turn the screw to open or close the clamp. Tighten all wires securely. The safety ground wire must be green. Other colors are for illustration purposes.

Ensure that double insulation is used on the area between the cable jacket and the connector. Refer to the area inside the dashed lines in the following figures.

400 VAC Connector

Maximum wire size: 8 AWG or 10 mm Maximum insulation diameter: 6.8 mm Wire stripping length: 13 - 15 mm

Optional ferrule suggestion: For 8 AWG: WAGO 216-289 For 10 AWG: WAGO 216-288 For 12 AWG: WAGO 216-287 For 14 AWG: WAGO 216-286 (Refer to manufacturer for details.)

208 VAC Connector

Maximum wire size: 6 AWG or 16 mm Maximum insulation diameter: 8.1 mm Wire stripping length: 12 mm

Strain Relief Bracket

You must install the strain relief bracket to ensure that the connector plug does not detach from the instrument during operation.

Fasten the power cable to the strain relief bracket as shown below, using the supplied tie wraps. This reduces weight and movement of the AC mains cable at the connector plug.

Make sure the connector plug is fully inserted.

Install the strain relief bracket using the four hex nuts.

Fasten the AC mains cable to the strain relief using the tie wraps.

34 Keysight N8900 Series Operating and Service Guide

Single Unit Connections

Output Connections

Single Load Connections

Multiple Load Connections

Remote Sense Connections

Positive and Negative Voltages

Output Connections

SHOCK HAZARD Turn off AC power before making rear panel connections.

All models generate voltages above 60 VDC, with some models rated at up to 1,500 VDC! Ensure that all instrument connections, load wiring, and load connections are insulated or covered -so that no accidental contact with lethal voltages can occur.

2 Operating Information

All rear panel connections must be made with the unit turned off, and must be performed by qualified personnel who are aware of the hazards involved. Improper actions can cause fatal injury as well as equipment damage.

Never touch cables or connections immediately after turning off the unit. Lethal voltages can remain between the output terminals up to 10 seconds after turn-off.

Ensure that any residual voltages present at the + and -output terminals are discharged before touching the output terminals. To fully discharge the output terminals, momentarily connect a DVM rated at 1,000 VDC between the + output terminal and ground. Repeat this procedure for the – output terminal. Do not use this DVM on units that are powered ON with voltages >1000 VDC.

Positive output terminal isolation is up to +1,500 V from ground and varies by model. Negative output terminal isolation is up to ±1,000 V from ground and varies by model.

The following factors should be considered when wiring the load to the power supply:

l Load wire current carrying capacity

l Load wire insulation rating (must be equivalent to the maximum output voltage)

l Load wire voltage drop

l Load wire noise and impedance effect

Keysight N8900 Series Operating and Service Guide 35

2 Operating Information

Wire Sizes

FIRE HAZARD To satisfy safety requirements, load wires must be large enough not to overheat when carrying the maximum short circuit current of the power supply. With more than one load, any pair of load wires must be capable of safely carrying the fullrated current of the supply.

The following table lists the characteristics of AWG (American Wire Gauge) copper wire. Paralleled wires may be substituted for single wires. For example, two AWG 3/0 (95 mm2) cables may be paralleled for units rated at 510 A. Paralleled load wires may be required for larger-ampacity power supplies.

AWG Nearest Metric size Ampacity (Note1) Resistance (Note2)

12 4 mm

10 6 mm

8 10 mm

6 16 mm

2 35 mm

1/0 50 mm

2/0 70 mm

3/0 95 mm

4/0 120 mm

up to 30 A 1.59

up to 40 A 1.0

up to 60 A 0.63

up to 80 A 0.395

up to 140 A 0.156

up to 195 A 0.098

up to 225 A 0.078

up to 260 A 0.062

up to 300 A 0.049

Note 1. Ampacity is based on a single conductor in free air, 26-30 °C ambient temperature, with the conductor rated at 60 °C. Ampacity ratings decrease when wires are bundled an at higher ambient temperatures. Note 2. Resistance is in ohms/1000 feet, at 20 °C wire temperature.

Along with conductor temperature, you must also consider voltage drop when selecting wire sizes. Although the power supply will compensate for the voltage in the load wires, it is recommended to minimize the voltage drop as much as possible to prevent excessive output power consumption from the power supply and poor dynamic response to load changes. Larger diameter wire sizes will help minimize load-wire voltage drops. Twisting or bundling load wires will help reduce transient voltage drops.

Single Load Connections

Ensure that the insulation rating of the load cables is greater than the voltage rating of the unit, which on some models is rated at up to 1500 VDC.

As shown in the following figure, terminate all load wires with the proper wire terminal lugs securely attached. DO NOT use unterminated wires when making connections at the power supply.

36 Keysight N8900 Series Operating and Service Guide

2 Operating Information

The following figures illustrates the recommended hardware sizes. A hardware kit is shipped with your unit. You must provide the cables and terminations. Ensure that the cable-mounting hardware does not short the output terminals.

Use the M8 diameter bolts, nuts, ring lugs, and washers - for models rated under 500 V. Maximum torque: 12.4 Nm (9.2 lb-ft).

Use the M6 diameter bolts, nuts, ring lugs, and washers - for models rated 500 V and up. Maximum torque: 7.3 Nm (5.4 lb-ft).

Route the load leads through the safety cover before attaching the safety cover to the rear panel. The following figures illustrate the two types of safety covers installed.

Large safety cover - for all models. Small safety cover - for models rated 500 V and up.

Units units rated 500 V and up use both safety cov-

ers.

Keysight N8900 Series Operating and Service Guide 37

2 Operating Information

Knockouts are provided on the large safety cover so that the load wires can be run in various directions. Note that heavy load cables must have some form of strain relief to prevent bending the safety cover or bus-bars.

Always twist or bundle the load wires to reduce lead inductance and noise pickup. The goal is to always minimize the loop area or physical space between the + and - load wires from the power supply to the load.

Multiple Load Connections

If you are using local sensing and are connecting multiple loads to one output, connect each load to the output terminals using separate load wires as shown in the following figure. This minimizes mutual coupling effects and takes full advantage of the power supply's low output impedance. Keep each wire-pair as short as possible and twist or bundle the wires to reduce lead inductance and noise pickup. The goal is to always minimize the loop area or physical space between the + and -load wires from the power supply to the load.

If load considerations require the use of distribution terminals that are located away from the power supply, twist or bundle the wires from the output terminals to the remote distribution terminals. Connect each load to the distribution terminals separately. Remote voltage sensing is recommended under these circumstances. Sense either at the remote distribution terminals or, if one load is more sensitive than the others, directly at the critical load.

38 Keysight N8900 Series Operating and Service Guide

2 Operating Information

Remote Sense Connections

When the sense leads are not connected to the load, the power supply will internally sense the voltage at the output terminals (referred to as local sensing), which regulates the output voltage at the output terminals. This does not compensate for the load lead voltage drop.

Remote sensing improves the voltage regulation at the load by monitoring the voltage at the load rather than at the output terminals. This lets the power supply compensate for the voltage drop in the load leads. Remote sensing is useful for CV operation with load impedances that vary or have significant lead resistance. It has no effect during CC operation. Because sensing is independent of other power supply functions, remote sensing can be used regardless of how the power supply is programmed.

Equipment Damage Always connect the + sense lead to the + terminal of the load and the - sense lead to the - terminal of the load. If a sense lead opens during operation the output may momentarily overshoot. The two center sense terminals are not used.

Connect the unit for remote sensing by connecting the sense leads as close as possible to the load. The power supply will automatically detect that the remote sense terminals are being used and will compensate for the load lead voltage drop.

Do NOT bundle the sense wire-pair together with the load wires; keep the load wires and sense wires separate. Keep the sense wire-pair as short as possible and twist or bundle it to reduce lead inductance and noise pickup.

Note that the sense leads carry only a few milliamperes of current and can be a much lighter gauge than the load cables. However, note that any voltage drop in the sense leads can degrade the output voltage regulation. Try to keep the sense lead resistance less than about 0.5 Ω per lead (this requires 20 AWG/1.0 mm2or heavier for a 50 foot length).

Keysight N8900 Series Operating and Service Guide 39

2 Operating Information

750 V to 1500 V Remote Sense Safety Cover

A remote-sense safety cover is provided and is required installation for all 750 V to 1500 V rated models. Always install the sense connector and safety cover even if you are not using the remote sense connections or the sharing connections.

Ensure that the insulation rating of the sense wires is greater than the voltage rating of the unit, which may be rated at up to 1500 VDC.

1. Route the sense wires (and the sharing wires if used) through the safety cover as shown in the figure.

2. Push the wires straight into the connector. Keysight recommends that you use a ferrule at the end of stranded wires to facilitate insertion. If you do not have a ferrule, use solid wire, or open the connector clamp by inserting a small flat-bladed screwdriver (a) as shown below. Then insert the wire (b), and remove the screwdriver. If you are using the sharing connections, insert the sharing wires at this time.

Important: Because of the pressure required, do not try to open the connector clamp while the connector is installed in the unit.

Wire cross section: 0.2 - 10 mm² (24 – 8 AWG)

Wire stripping length 15 mm

3. Install the sense connector. Push on the connector until it clicks into place. Also install the sharing

connector.

4. Install the safety cover on the rear panel as shown in the figure. First remove the screw next to the sharing connector. Hook the right side of the safety cover in the vent opening. Attach the left side of the cover using the captive Torx screw.

40 Keysight N8900 Series Operating and Service Guide

2 Operating Information

Over-voltage Protection

Remote over-voltage protection (OVP) provides a customer-configurable over-voltage protection. When combined with remote voltage sensing, this allows for more precise voltage protection directly at the load. The OVP circuit monitors the voltage at the + and – sense terminals if they are connected to the load, or at the output terminals if the sense terminals are not being used. Refer to Programming

Output Protection for further information.

Output Noise

Any noise picked up on the sense leads will appear at the output terminals and may adversely affect CV load regulation. Twist the sense leads or use a ribbon cable to minimize the pickup of external noise. In extremely noisy environments it may be necessary to shield the sense leads. Ground the shield at the power supply end only; do not use the shield as one of the sensing conductors.

Positive and Negative Voltages

Either positive or negative voltages with respect to ground can be obtained from the output by grounding (or "commoning") one of the output terminals. Always use two wires to connect the load to the output regardless of where or how the system is grounded.

Positive output terminal isolation is up to +1,500 V from ground and varies by model. Negative output terminal isolation is up to ±1,000 V from ground and varies by model.

Equipment Damage Before grounding any output terminal, check to see if the load is already grounded. Incorrect grounding could result in a short circuit.

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Multiple Unit Connections

Parallel Connections

Series Connections

Sharing Connections

Group Connections

SHOCK HAZARD Turn off AC power before making rear panel connections.

Never touch cables or connections immediately after turning off the unit. Lethal voltages can remain between the output terminals up to 10 seconds after turn-off.

Positive output terminal isolation is up to +1,500 V from ground and varies by model. Negative output terminal isolation is up to ±1,000 V from ground and varies by model.

Parallel Connections

SHOCK HAZARD Using bus bars negates the safety function of the safety covers, as the exposed portion of the bus bar creates a shock hazard.

Equipment Damage Only connect power supplies that have identical voltage and current ratings in parallel.

Connecting power supplies in parallel provides a greater current capability than can be obtained from a single unit. The figure below shows how to connect three units in parallel. If desired, up to 10 units may be connected in parallel. For model N8957APV, up to 14 units may be connected in parallel.

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If remote sensing is desired to compensate for the lead drops, connect the remote sense leads of the Master unit directly to the load (see Group Operation). Remote sensing is recommended, but not required.

Bus bars can be used instead of cables to parallel the output terminals in a stacked configuration. Place the bus bars on the inside of the output terminals. Keep the wiring from the power supply to the load as short as possible and twist or bundle the leads to reduce lead inductance and noise pickup. The goal is to always minimize the loop area or physical space between the + and - output leads from the power supply to the load.

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Series Connections

SHOCK HAZARD Series connections are not allowed as floating voltages must not exceed the ratings given in the specifications table.

Sharing Connections

Only N8900A units labeled Version 2b, 2c, 3b, or 3c on the rear label can current-share with other units similarly labeled. This limitation does not affect N8937APV or N8957APV models.

The Sharing terminals must be connected for parallel operation as shown in the previous figure. For further information about current sharing, refer to Current Sharing Operation. The following figure details the Sharing bus connections for multiple units.

Group Connections

A Group or master/slave configuration can also be used when connecting units in parallel as shown in the figure. This allows one designated unit to be the master controller of all of the units connected in the group. Grouped connections use a digital RS485 bus. Connections are made using standard CAT5 or better cables. For further information about group configurations, refer to Group Operation.

Do not connect an Ethernet port to a Group connector.

The following figure details the termination switch settings for the grouped units. Only the first and last units in the connection chain need to have the switch set to the "terminated" position.

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Group Connections

Switches up -unterminated, normal

Switches down - terminated, only for units at the beginning and end of the instrument chain

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External Control Signal Connections (Analog)

External control signal connections are made through the 15 pin "Analog" connector (Type: Sub-D, DSub) on the rear of the unit. Use a standard connector plug (customer-supplied) to make all connections. Remember to turn of the unit before making any rear panel connections.

Equipment Damage The external control interface is galvanically separated from DC output and referenced to earth ground. Therefore never connect a ground from the external control interface to the +DC or -DC outputs. Use an isolated, ungrounded, programming source to prevent ground loops when using the external control interface.

Pin Assignments

The following figure identifies the pins on the external control signal connector (labeled "Analog" on the rear panel).

You must provide the mating plug that for the external control signal connector. Use a 15-pin Dsubminiature connector.

For information on using the external control functions refer to External Control Signal Programming.

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Interface Connections

GPIB Connections

USB Connections

LAN Connections - site and private

This section describes how to connect to the various communication interfaces on your power supply. For further information about configuring the remote interfaces, refer to Remote Interface

Configuration.

If you have not already done so, install the Keysight IO Libraries Suite, which can be found at

www.keysight.com/find/iolib.

For detailed information about interface connections, refer to the documentation included with the Keysight IO Libraries Suite.

GPIB Connections

The following figure illustrates a typical GPIB interface system.

1. Connect your instrument to the GPIB interface card using a GPIB interface cable.

2. Use the Connection Expert utility of the Keysight IO Libraries Suite to configure the GPIB card’s parameters.

3. You can now use Interactive IO within the Connection Expert to communicate with your instrument, or you can program your instrument using the various programming environments.

USB Connections

The following figure illustrates a typical USB interface system.

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1. Connect your instrument to the USB port on your computer.

2. With the Connection Expert utility of the Keysight IO Libraries Suite running, the computer will automatically recognize the instrument. This may take several seconds. When the instrument is recognized, your computer will display the VISA alias, IDN string, and VISA address. This information is located in the USB folder.

3. You can now use Interactive IO within the Connection Expert to communicate with your instrument, or you can program your instrument using the various programming environments.

LAN Connections - site and private

Equipment DamageNever insert a network cable which is connected to Ethernet or its components into the master- slave socket on the back side of the unit.

A site LAN is a local area network in which LAN-enabled instruments and computers are connected to the network through routers, hubs, and/or switches. They are typically large, centrally-managed networks with services such as DHCP and DNS servers. The following figure illustrates a typical site LAN system.

A private LAN is a network in which LAN-enabled instruments and computers are directly connected, and not connected to a site LAN. They are typically small, with no centrally-managed resources. The following figure illustrates a typical private LAN system.

1. Connect the instrument to the site LAN or to your computer using a LAN cable. The as-shipped instrument LAN settings are configured to automatically obtain an IP address from the network using a DHCP server (DHCP is set On). The DHCP server will register the instrument’s hostname with the dynamic DNS server. The hostname as well as the IP address can then be used to communicate with the instrument. If you are using a private LAN, you can leave all LAN settings as they are. Most Keysight products and most computers will automatically choose an IP address using auto-IP if a DHCP server is not present. Each assigns itself an IP address from the block 169.254.nnn. The front panel Lan indicator will come on when the LAN port has been configured.

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2. Use the Connection Expert utility of the Keysight IO Libraries Suite to add the Keysight N8900 models and verify a connection. To add the instrument, you can request the Connection Expert to discover the instrument. If the instrument cannot be found, add the instrument using the instrument’s hostname or IP address.

3. You can now use Interactive IO within the Connection Expert to communicate with your instrument, or you can program your instrument using the various programming environments. You can also use the Web browser on your computer to communicate with the instrument as described under Using the

Web Interface.

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2 Operating Information

Getting Started

Turn the Unit On

Set the Output Voltage

Set the Output Current

Set the Over-Voltage Protection

Enable the Output

Use the Built-in Help System

Turn the Unit On

Verify that the line cord is connected and plugged in to the correct AC line voltage.

Turn the unit on with the front panel power switch. Rotate the knob from 0 to 1. The front panel display will light up after a few seconds. A power-on self-test occurs automatically when you turn the unit on. This test assures you that the power supply is operational.

It may take about 30 seconds or so for the power supply to initialize before it is ready for use.

If the instrument does not turn on, verify that the power cord is firmly connected. Also make sure that the instrument is connected to an energized power source.

If the power-on self test fails, the display shows ERR in the lower right corner. See SCPI Error

Messages for information on error codes. See Service and Repair -Introduction for instructions on

returning the instrument for service.

Set the Output Voltage

Method 1

Turn the Voltage knob to set the output voltage. The setting value appears in the Set field on the bottom of the display.

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Method 2

Use the left and right navigation keys to navigate to the setting that you wish to change.

In the following display, the voltage setting is selected. Enter a value using the numeric keypad. Then press Select.

You can also use the numeric arrow keys to adjust the value up or down. Values become effective when the output is enabled.

Method 3

Use the Voltage key to select the voltage entry field. In the display below, the voltage setting is selected. Enter the desired setting using the numeric keypad.Then press Enter.

If you make a mistake, either use the backspace key to delete the number, press Back to back out of the menu, or press Meter to return to meter mode.

Set the Output Current

Method 1

Turn the Current knob to set the output current. The setting value appears in the Set field on the bottom of the display.

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Method 2

Use the left and right navigation keys to navigate to the setting that you wish to change.

In the display below, the current setting is selected. Enter a value using the numeric keypad. Then press Select.

You can also use the numeric arrow keys to adjust the value up or down. Values become effective when the output is turned on.

Method 3

Use the Current key to select the current entry field. In the display below, the current setting is selected. Enter the desired setting using the numeric keypad. Then press Select.

If you make a mistake, either use the backspace key to delete the number, press Back to back out of the menu, or press Meter to return to meter mode.

Set the Over-Voltage Protection

Use the front panel menu.

The front panel command menu lets you access most of the power supply’s functions. The actual function controls are located at the lowest menu level. Briefly:

Pressthe Menu key to access the command menu.

Pressthe left and right (<, >)navigation keys to move across the menu commands.

Pressthe center Select key to select a command and move down to the next level in the menu.

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Pressthe Help key at the lowest menu level to display help information about the function controls.

To exit the command menu press the Meter key to immediately return to meter mode, or press the

Menu key to return to the top level.

For a map of the front panel menu commands, refer to Front Panel Menu Reference.

Menu example - accessing over-voltage protection.

Press the Menu key to access the front panel command menu. The first line identifies the menu path. When the menu is first accessed, the menu is at the top or root, and the path is empty. The second line indicates the commands that are available at the present menu level. In this case, the top-level menu commands are shown, with the Output command highlighted. The third line indicates which commands are available under the Output command. If there are no lower level commands, a brief description of the highlighted command is displayed.

Press the right arrow navigation key > to traverse the menu until the Protect command is highlighted. Press the Select key to access the Protect commands.

Since the OVP command is already highlighted, press the Select key to access the OVP dialog.

Note that the default OVP setting for all models is 120% of the rated ouptut voltage. You can change the OVP setting using the numeric entry keys. Then press Select. Press the Meter key to return to meter view.

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Enable the Output

Use the On/Off key to enable the output. If a load is connected to the output, the front panel display will indicate that it is drawing current. Otherwise, the current reading will be zero. The status indicator shows the output’s status. In this case, "CV" indicates the output is in constant voltage mode.

If the output current is set to zero, the output voltage may remain as zero when the output is enabled, and a UNRstatus may appear in the display. You must program a minimum current value for the output voltage to rise to its programmed setting.

For a description of the status indicators, refer to Front Panel Display at a Glance.

Use the Built-in Help System

View the list of help topics.

Press the Help key to view the context-sensitive help. Information about the present display is presented.

Press Meter or Back to exit Help.

View the help information for displayed messages.

Whenever a limit is exceeded or any other invalid configuration is found, the instrument will display a message, including Error code information.

Press Meter or Back to exit Help.

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Remote Interface Configuration

USB Configuration

GPIB Configuration

LAN Configuration

Modifying the LAN Settings

Using the Web Interface

Using Telnet

Using Sockets

Interface Lockout

This instrument supports remote interface communication over three interfaces: GPIB, USB, and LAN. All three interfaces are "live" at power up. To use the interfaces, you must first install the Keysight IO Libraries software, found at www.keysight.com/find/iolib.

The front panel IO indicator comes on whenever there is activity on the remote interfaces. The front panel Lan indicator comes on when the LAN port is connected and configured.

This instrument provides Ethernet connection monitoring. With Ethernet connection monitoring, the instrument’s LAN port is continually monitored, and automatically reconfigured when the instrument is unplugged for a minimum of 20 seconds and then reconnected to a network

USB Configuration

There are no configurable USB parameters. You can retrieve the USB connect string using the front panel menu:

Front Panel Menu SCPI Command

Select System\IO\USB

The dialog displays the USB connect string.

Not available

GPIB Configuration

Each device on the GPIB (IEEE-488) interface must have a unique whole number address between 0 and 30. The instrument ships with the address set to 5. Your computer’s GPIB interface card address must not conflict with any instrument on the interface bus. This setting is non-volatile; it will not be changed by power cycling or *RST. Use the front panel menu to change the GPIB address:

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Front Panel Menu SCPI Command

Select System\IO\GPIB

Use the numeric keys to enter a new value from 0 to 30. Then press Enter.

Not available

LAN Configuration

The following sections describe the primary LAN configuration functions on the front-panel menus. Note that there are no SCPI commands to configure the LAN parameters. All LAN configuration must be done from the front panel.

After changing the LAN settings, you must Save the changes. Select: System\IO\LAN\Apply. Selecting Apply activates the settings. LAN settings are nonvolatile, they will not be changed by power cycling or *RST. If you do not want to save your changes select: System\IO\LAN\Cancel. Selecting Cancel cancels all changes.

When shipped, DHCP is on, which may enable communication over LAN. The letters DHCP stands for Dynamic Host Configuration Protocol, a protocol for assigning dynamic IP addresses to devices on a network. With dynamic addressing, a device can have a different IP address every time it connects to the network.

Viewing Active Settings

To view the currently active LAN settings:

Front Panel Menu SCPI Command

Select System\IO\LAN\Settings

Displays the active LAN settings. Use the up and down arrow key to scroll through the list.

Not available

The currently active settings for the IP Address, Subnet Mask, and Default Gateway may be different from the front panel configuration menu settings -depending on the configuration of the network. If the settings are different, it is because the network has automatically assigned its own settings

Resetting the LAN

You can perform an LXI LCI reset of the LAN settings. This resets DHCP, DNS server address configuration, mDNS state, and web password. These settings are optimized for connecting your instrument to a site network. They should also work well for other network configurations.

You can also reset the LAN to the as-shipped settings. This returns ALLLAN settings to the as-shipped values and restarts networking. All default LAN settings are listed under Non-volatile Settings.

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Front Panel Menu SCPI Command

2 Operating Information

Select System\IO\LAN\Reset Select System\IO\LAN\Defaults

Select Reset. This activates the selected LAN settings and restarts networking.

Not available

Modifying the LAN Settings

IP Address

Select IP to configure the addressing of the instrument. Press the Menu key, then select System\IO\LAN\Config\IP. The configurable parameters include:

Front Panel Menu SCPI Command

Select System\IO\LAN\Modify\IP

Select Auto or Manual. See below for a full description.

Auto - automatically configures the addressing of the instrument. When selected, the instrument will

first try to obtain an IP address from a DHCP server. If a DHCP server is found, the DHCP server will assign an IP address, Subnet Mask, and Default Gateway to the instrument. If a DHCP server is unavailable, the instrument will try to obtain an IP address using AutoIP. AutoIP automatically assigns an IP address, Subnet Mask, and Default Gateway addresses on networks that do not have a DHCP server.

Not available

Manual - allows you to manually configure the addressing of the instrument by entering values in the

following three fields. These fields only appear when Manual is selected.

IP Address - This value is the Internet Protocol (IP) address of the instrument. An IP address is

required for all IP and TCP/IP communications with the instrument. An IP Addressconsists of 4 decimal numbers separated by periods. Each decimal number ranges from 0 through 255 with no leading zeros. Note that the Internet Engineering Task Force reserved the IP address range of 169.254.1.0 to 169.254.254.255 for link-local addressing (auto-IP). Do not assign a manual IP address within this range.

Subnet Mask - This value is used to enable the instrument to determine if a client IP addressis on the

same local subnet. The same numbering notation appliesas for the IP Address. When a client IP address is on a different subnet, all packets must be sent to the Default Gateway.

DEF Gateway - Thisvalue isthe IP Address of the default gateway that allows the instrument to com-

municate with systems that are not on the local subnet, as determined by the subnet mask setting. The same numbering notation applies as for the IP Address. A value of 0.0.0.0 indicates that no default gateway is defined.

Dot-notation addresses ("nnn.nnn.nnn.nnn" where "nnn" is a byte value from 0 to 255) must be expressed with care, as most PC web software interprets byte values with leading zeros as octal (base 8) numbers. For example, "192.168.020.011" is actually equivalent to decimal "192.168.16.9" because ".020" is interpreted as "16" expressed in octal, and ".011" as "9". To avoid confusion, use only decimal values from 0 to 255, with no leading zeros.

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Host Name

A hostname is the host portion of the domain name, which is translated into an IP address. To configure the hostname of the instrument:

Front Panel Menu SCPI Command

Select System\IO\LAN\Modify\Name

You can enter any value from the numeric keypad. For additional characters, use the up/down navigation keys to enter an alpha character by scrolling through the selection list that appears when you press the keys. Use the backspace key to delete a value. Press Enter when you are finished.

Not available

Host Name - This field registers the supplied name with the selected naming service. If the field is left blank, no name is registered. A hostname may contain upper and lower case letters, numbers and dashes (-). The maximum length is 15 characters.

Each instrument is shipped with a default hostname with the format: A-modelnumber-serialnumber, where modelnumber is the unit’s 6-character model number (e.g. N6950A), and serialnumber is the last five characters of the 10-character serial number located on the label on the top of the unit (e.g. 45678 if the serial number is MY12345678).

DNS Server and WINS Server

DNS is an internet service that translates domain names into IP addresses. It is also needed for the instrument to find and display its hostname assigned by the network. Normally, DHCP discovers the DNS address information; you only need to change this if DHCP is unused or not functional.

WINS configures the Windows service of the instrument. This is similar to the DNS service that translates domain names into IP addresses.

To manually configure the DNS and WINS services:

Front Panel Menu SCPI Command

Select System\IO\LAN\Modify\DNS or Select System\IO\LAN\Modify\WINS

Select Primary Address or Secondary Address. See below for a full description.

Primary Address - This field enters the primary address of the server. Contact your LAN administrator

Not available

for server details.The same numbering notation applies as for the IP Address.A value of 0.0.0.0 indicates that no default server is defined.

Secondary Address - This field enters the secondary address of the server. Contact your LAN admin-

istrator for server details.The same numbering notation applies as for the IP Address.A value of

0.0.0.0 indicates that no default server is defined.

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mDNS Service Name

The mDNS service name is registered with the selected naming service. To configure the mDNS service name of the instrument:

Front Panel Menu SCPI Command

Select System\IO\LAN\Modify\mDNS

mDNS Service Name - This field registers the service name with the selected naming service. If the

Not available

field is left blank, no name is registered. A service name may contain upper and lower case letters, numbers and dashes(-).

l Each instrument is shipped with a default service name with the format: Keysight-modelnumber-

description-serialnumber, where modelnumber is the unit’s 6-character model number (e.g. N6950A), description is the description, and serialnumber is the 10-character serial number located on the label on the top of the unit (e.g. MY12345678).

Services

This selects the LAN services to enable or disable.

Front Panel Menu SCPI Command

Select System\IO\LAN\Modify\Services

Check or uncheck the services that you wish to enable or disable.

l The configurable services include: VXI-11, Telnet, Web control, Sockets, and mDNS.

l You must enable Web control if you wish to remotely control your instrument using its built-in Web

Not available

interface.

Using the Web Interface

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Your power supply has a built-in Web interface that lets you control it directly from the Web browser on your computer. With the Web interface, you can access the front panel control functions including the LANconfiguration parameters. Up to six simultaneous connections are allowed. With multiple connections, performance will be reduced.

The built-in Web interface only operates over the LAN. It requires Internet Explorer 7+. You also need the Java Plug-in version 7+. This is included in the Java Runtime Environment.

The Web interface is enabled when shipped. To launch the Web interface:

Open the Web browser on your computer.

Enter the instrument’s hostname or IP addressinto the browser’s Address field. The following home page will appear.

Click on the Browser Web Control button in the navigation bar on the left to begin controlling your instrument.

For additional help about any of the pages, click on the Help with this Page button.

If desired, you can control access to the Web interface using password protection. As shipped, no password is set. To set a password, click on the View & Modify Configuration button. Refer to the online help for additional information about setting a password.

Using Telnet

In an MS-DOS Command Prompt box type: telnet hostname 5024 where hostname is the instrument's hostname or IP address, and 5024 is the instrument’s telnet port.

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You should get a Telnet session box with a title indicating that you are connected to the power supply. Type the SCPI commands at the prompt.

Using Sockets

Power supplies allow any combination of up to six simultaneous data socket, control socket, and telnet connections to be made.

Keysight instruments have standardized on using port 5025 for SCPI socket services. A data socket on this port can be used to send and receive ASCII/SCPI commands, queries, and query responses. All commands must be terminated with a newline for the message to be parsed. All query responses will also be terminated with a newline.

The socket programming interface also allows a control socket connection. The control socket can be used by a client to send device clear and to receive service requests. Unlike the data socket, which uses a fixed port number, the port number for a control socket varies and must be obtained by sending the following SCPI query to the data socket: SYSTem:COMMunicate:TCPip:CONTrol?

After the port number is obtained, a control socket connection can be opened. As with the data socket, all commands to the control socket must be terminated with a newline, and all query responses returned on the control socket will be terminated with a newline.

To send a device clear, send the string “DCL” to the control socket. When the power supply has finished performing the device clear it echoes the string “DCL” back to the control socket.

Service requests are enabled for control sockets using the Service Request Enable register. Once service requests have been enabled, the client program listens on the control connection. When SRQ goes true the instrument will send the string “SRQ +nn” to the client. The “nn” is the status byte value, which the client can use to determine the source of the service request.

Interface Lockout

The USB interface, LAN interface, and the Web server are enabled when shipped. To enable or disable the interfaces from the front panel:

Front Panel Menu SCPI Command

Select System\Admin\IO

Enable or disable the interfaces by checking or unchecking the following items:

Not available

Enable LAN, Enable GPIB, and Enable USB. Then press Select.

If you cannot access the Admin menu, it may be password protected.

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Using the Power Supply

This section contains details on using the instrument, including front panel and remote interface operation. You may want to read Front-Panel Menu Reference first. See SCPI Programming Reference for details on the SCPI commands to program the instrument. This section covers:

Programming the Output

Programming Output Protection

Programming Output Steps

Making Measurements

Parallel Operation

External Control Signal Programming

System-Related Operations

Operating Mode Tutorial

SASimulator Operation - applies to N8937APV and N8957APV models only

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Programming the Output

When the power supply is first turned on, it may take about 30 seconds or so to initialize the unit before it is ready for use.

Set the Output Voltage

Set the Output Current

Enable the Output

Set the Output Voltage

You can set the output voltage when the output is either disabled (OFF) or enabled (ON). When enabled, the output voltage will rise to the programmed setting. This assumes that a minimum output current has been programmed, that the output has not reached its current limit or power limit boundary.

Front Panel Menu SCPI Command

Turn the Voltage knob while observing the voltage setting; or press the Voltage key and enter a value. Then press Select.

To set the output voltage to 90 volts:

VOLT 90

When the unit is operating in constant voltage mode, CV status is displayed on the front panel.

Set the Output Current

You can set the output current when the output is either disabled (OFF) or enabled (ON). When enabled, the output current will be limited at its programmed setting.

Front Panel Menu SCPI Command

Turn the Current knob while observing the current setting; or press the Current key and enter a Value. Then press Select.

To set the output current to 100 amps:

CURR 100

When the unit is operating in constant current mode, CC status is displayed on the front panel.

Enable the Output

Front Panel Menu SCPI Command

Press the On/Off key. To turn the output on or off: OUTP ON|OFF

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Programming Output Protection

Set the Over-Voltage Protection

Set the Over-Current Protection

Clear Output Protection

The Keysight N8900 series power supplies have many protection functions. A front panel status indicator will turn on when a protection function has been set. Most protection functions are latching, which means that they must be cleared once they have been set. Of the following protection functions, only the OV and OC are user-programmable.

OV Over-Voltage protection is a hardware OVP whose trip level is a user-pro-

grammable value. The OVP is always enabled.

OC Over-Current protection is a user-programmable function that can be enabled or

disabled. When enabled, the output will be disabled when the output current reaches the current limit setting.

OT Over-Temperature protection monitors the internal temperature of the power

supply and disables the output if the temperature exceeds the factory-defined limit. The OT protection is always enabled.

PF Power-Fail indicates that a low voltage condition on the AC mains has occurred

and has disabled the output. The PF protection is always enabled.

MSP Master/Slave Protection indicates that a fault has occurred in the paralleled

group. The outputs of all grouped units are disabled. MSP is always enabled.

Set the Over-Voltage Protection

The over-voltage protection will turn the output off if the output voltage reaches the programmed over-voltage limit. The OVP circuit monitors the voltage at the + and – sense terminals if they are connected to the load, or at the output terminals if the sense terminals are not being used.

Front Panel Menu SCPI Command

Select Protect\OVP

Enter the value in the OVP level box. Then press Select.

To set the OVP level to 55 volts:

VOLT:PROT 55

Set the Over-Current Protection

When over-current protection is enabled, the power supply turns off the output if the output current reaches the current limit setting and transitions from CV to CC mode.

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Front Panel Menu SCPI Command

2 Operating Information

Select Protect\OCP

Check Enable OCP. Then press Select.

To enable OCP:

CURR:PROT:STAT ON

You can also specify an OCP delay to prevent momentary output settings, load, and status changes from tripping the over-current protection. In most cases these momentary conditions would not be considered an over-current protection fault, and having an OCP condition disable the output when they occur would be a nuisance. Specifying an OCP delay lets the OCP circuit ignore these momentary changes during the specified delay period. Once the OCP delay time has expired and the over-current condition persists, the output will shut down.

Front Panel Menu SCPI Command

Select Protect\OCP

Enter a delay value. Then press Select.

To specify a 10 millisecond delay:

CURR:PROT:DEL 0.01

Factors that influence how long the settings change or output load change may last include: difference between old output value and new output value, the current limit setting, and the load capacitance in CV mode or load inductance in CC mode. The delay required must be determined empirically; the output programming-response time characteristics may be used as guidelines.

Note that the time it takes the output to go into CC mode varies - depending on the magnitude of the over-current condition compared to the current limit setting. For example, if the over-current is only slightly greater than the current limit setting, it may take several tens of milliseconds for the output to set the CC status bit. If the over-current is significantly greater than the current limit setting, it may only take a few hundred microseconds or less for the output to set the CC status bit. To determine when the output will shut down, you must add the time it takes for the CC status bit to the overcurrent protection delay time. If the over-current persists beyond the sum of these two time intervals, the output will shut down.

Clear Output Protection

If an over-voltage, over-current, over-temperature, power-fail condition, or master/slave protection occurs, the output is disabled. The appropriate operating status indicator on the front panel will be on. To clear the protection function and restore normal operation, first remove that condition that caused the protection fault. Then, clear the protection function as follows:

Front Panel Menu SCPI Command

Select Protect\Clear

Select Clear.

MSP protection cannot be cleared using Protect\Clear. It can only be cleared by cycling power or re-discovering the slave units (see Group Configuration).

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To clear a protection fault:

OUTP:PROT:CLE

2 Operating Information

Programming Output Steps

The transient system of the Keysight N8900 HPS lets you generate output steps. An output step is a one-time event that steps the output voltage or current up or down in response to a trigger. The following steps are required to generate a triggered output step:

Enable the output to respond to step triggers

Program the voltage or current step levels

Initiate the transient system

Trigger the output step

Enable the output to respond to step triggers

First, you must enable the output to respond to Step triggers. Unless an output is enabled to respond to triggers, nothing will happen even if you have programmed a trigger level and generated a trigger for the output.

Front Panel Menu SCPI Command

Select Transient\Mode.

For voltage step triggering, set the transient mode to Step. For current step triggering, set the transient mode to Step.

Then press Select.

To enable the transient function to respond to step triggers, use:

VOLT:MODE STEP

CURR:MODE STEP

In Step mode, the triggered value becomes the immediate value when the trigger is received. In Fixed mode, trigger signals are ignored; the immediate values remain in effect when a trigger is received.

Program the voltage or current step levels

Next, use the following commands to program a triggered level. The output will go to this level when the trigger is received.

Front Panel Menu SCPI Command

Select Transient\Step.

Select the Trig Voltage box to set the voltage. Select the Trig Current box to set the current.

Enter a value and press Select.

To set a voltage step level to 55 V, and a current step level to 110 A, use:

VOLT:TRIG 55 CURR:TRIG 110

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2 Operating Information

Initiate the transient system

When the unit is turned on, the trigger system is in the idle state. In this state, the trigger system is disabled, ignoring all triggers. The INITiate commands enable the trigger system to receive triggers.

Front Panel Menu SCPI Command

Not available To initiate the transient trigger system:

INIT:TRAN

It takes a few milliseconds for the instrument to be ready to receive a trigger signal after receiving the INITiate:TRANsient command. If a trigger occurs before the trigger system is ready for it, the trigger will be ignored. You can test the WTG_tran bit in the operation status register to know when the instrument is ready to receive a trigger.

Front Panel Menu SCPI Command

Not available To query the WTG_tran bit (bit 4):

STAT:OPER:COND?

If a bit value of 16 is returned in the query, the WTG_tran bit is true, and the instrument is ready to receive the trigger signal. Refer to Status Tutorial for more information.

Trigger the output step

The trigger system is waiting for a trigger signal in the initiated state. Trigger the transient as follows:

Front Panel Menu SCPI Command

Not available To generate a transient trigger:

TRIG:TRAN

Alternatively, you can also program a *TRG or an IEEE-488 <get> command.

If the trigger does not occur, you must manually return the trigger system to the idle state. The following commands return the trigger system to the idle state:

Front Panel Menu SCPI Command

Not available

When a trigger is received, the triggered functions are set to their programmed trigger levels. When the triggered actions are completed, the trigger system returns to the idle state.

ABOR:TRAN

You can test the TRAN_active bit in the Operation Status register to know when the transient trigger system has returned to the idle state.

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2 Operating Information

Front Panel Menu SCPI Command

Not available To query the TRAN_active bit (bit 6):

STAT:OPER:COND?

If a bit value of 64 is returned in the query, the TRAN_active bit is true, and the transient action is NOT complete. When the TRAN_active bit is false, the transient action is complete. Refer to Status Tutorial for more information.

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2 Operating Information

Making Measurements

The Keysight N8900 series has fully integrated voltmeter and ammeter to measure the actual voltage and current that is being supplied to the load. Whenever the instrument is on, the front panel automatically measures output voltage and current.

Power measurements are derived from the voltage and current measurements.

Average (DC) Measurements

Use the following commands to make a measurement:

Front Panel Menu SCPI Command

Select the Meter key.

Repeatedly press this key to cycle through the following measurement functions: Voltage, Current Voltage, Power Voltage, Current, Power

To measure average (DC) output voltage, current, or power:

MEAS:VOLT? MEAS:CURR? MEAS:POW?

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2 Operating Information

Parallel Operation

Current Sharing Operation

Group Operation

Group Configuration

Group Protection

Series Operation

Parallel operation provides the possibility of connecting a number of devices together to create a system with higher total current and, hence, higher power. Refer to Parallel Connections for detailed information on how to connect the outputs, share cables, and master/slave cables.

Current Sharing Operation

Only N8900A units labeled Version 2b, 2c, 3b, or 3c on the rear label can current-share with other units similarly labeled. This limitation does not affect N8937APV or N8957APV models.

The current Sharing cables must be connected on all paralleled units as previously described under Parallel Connections. The current sharing cables allow identical units to share current approximately equally in voltage priority mode. The current sharing operation works as follows:

l Program the output voltage of each paralleled unit to the same value.

l Set the current limit of each paralleled unit so as not to interfere with the expected current sharing

level. When the current limit setting of any paralleled unit is reached, the output current of that unit will limit at its specified setting. If the current limit of the remaining units is set to a higher value, those units will continue to share current until their current limit is reached.

l Current sharing continues until the total current limit of the paralleled group is reached. This allows

current to be shared among participating units without any additional external connections or programming considerations.

Group Operation (master/slave)

In addition to the current Share function, which must be used with paralleled units, you can also Group the paralleled units, with one unit configured as a master controlling all of the slave units. Grouping units provides the following benefits:

l Program the Output, Transient, Protect, and Statesfunctions on only one unit. The programmed set-

tings will automatically be distributed to the connected units.

l The master unit displays, or makes available to be read by the remote controller, the sum of the actual

current values of all the units. The output current of the slave units can be queried individually.

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2 Operating Information

l The range for setting the values of the master unit is dependent on the number of paralleled units. For

example, if 5 units each with a current rating of 90 A are connected to form a 450 A system, then the master can be programmed to provide current in the range from 0 to 450 A.

l The Group configuration is saved in non-volatile memory.

Group Configuration

A maximum of 1 master and up to 9 slave units can be grouped. For model N8957APV only, 1 master and up to 13 slave units may be connected in parallel.

To configure the units in a paralleled master/slave group:

Configure the Unit as either a Master or Slave

The current SHARE cables must first be connected on all paralleled units as previously described under Paralleled Connections. The units at the end of the grouped connection chain must be terminated by setting the DIP switch located on the rear panel (see Parallel Connections).

Turn the outputs of all paralleled units off. If the output of any paralleled unit is on, and you try to configure any of the menu items, a status message will indicate “Output must be off to change configuration".

Front Panel Menu SCPI Command

Select System\Group\Function

In the dialog box, select either Master or Slave. Only select None if the unit is not paralleled. Then press Select.

Not available

When a unit has been configured as a slave, the following functions will be disabled, as these will be controlled by the master unit:

l Output On/Off.

l Voltage and Current setting controls.

l Output, Transient, Protect, and States menu functions.

The SCPI commands that correspond to the above functions are also disabled.

Specify the Address of Each Slave Unit

If the Slave selection is grayed out (unavailable) it means that the unit has not been configured as a slave in the Function menu.

Front Panel Menu SCPI Command

Select System\Group\Slave

In the dialog box, select the address of the slave. Values can range from 1 - 15. Then press Select.

Not available

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2 Operating Information

View the Configured Slave Unit Addresses

If the Master selection is grayed out (unavailable) it means that the unit has not been configured as a master in the Function menu. If the master had previously been configured, a list of slave unit addresses are displayed in the Configured box.

Front Panel Menu SCPI Command

Select System\Group\Master

The Configured field displays the addresses of all connected and configured Slave units.

If the Configured field is blank, press Discover Slaves to discover and display the addresses of the connected units.

Not available

Group Protection

The following protection features are implemented in a master/slave configuration:

Power On At power-on, all master/slave units will have their outputs off (unless they have been

configured by the *RCL0 command to be programmed on).

Configuration check

Communications check

At power on, the master unit will search for the slave units and compare the list of slaves found with the previously stored configuration. If the lists match, normal operation continues. If the lists do not match, a Master/Slave Protection (MSP) fault occurs and the outputs of all units remain off (see Programming Output Protection). A message is placed in the Error Queue that lists the slave units found and the slave units expected.

If a master unit loses communication with any slave at any time, it will generate an MSP fault, which turns its own output off as well as the outputs of the slaves that it can still communicate with. If a slave loses communication with the master, the slave will also turn its output off.

Inhibit function The Fault/Inhibit function can be used to shut down all outputs in response to a signal on

the Inhibit input pin. In a master/slave configuration, only the master unit controls the inhibit function of the slave units. Do not connect the Inhibit inputs and Fault outputs on any slave units. The Inhibit mode is stored in non-volatile memory.

Series Operation

SHOCK HAZARD Series operation is not allowed as floating voltages must not exceed the ratings given in the specifications table.

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2 Operating Information

External Control Signal Programming

The analog interface on the rear of the instrument provides the following capability:

Analog Programming of Voltage and Current

Output Turn On Control in Analog Mode

Analog Monitoring of Voltage and Current

Monitoring Instrument Status

Output On/Off Control

Fault/Inhibit System Protection

Extending Fault/Inhibit Protection

Pin Descriptions and Characteristics

Equipment Damage The digital and analog ground pins are internally connected to the USB and GPIB grounds. Only connect these pins to external circuitry that is either at earth ground potential or, to avoid ground loops, float the connections.

This section describes the programming capability of the analog interface with firmware version A.02.00 and up. For a brief description of the differences between this version and previous firmware versions, refer to Manual Backdating.

The OVP level and the OCP settings cannot be programmed using external control signals. They can still be programmed using the front panel or SCPI commands while the external control signal interface is enabled.

Analog Programming of Voltage and Current

Analog programming of voltage and current as described in this section is not available in Master/Slave configurations.

Analog programming of voltage and current is not available on Models N8737APV and N8957APV.

Specify the Analog Reference Voltage

You can specify either a 5 V or a 10 V reference voltage.

Front Panel Menu SCPI Command

Select System\IO\Analog.

Select either the 5 V or 10 V reference voltage. Then press Select.

Keysight N8900 Series Operating and Service Guide 73

Not available

2 Operating Information

Enable the Voltage and Current Analog Inputs

Enable analog programming of the output voltage and current by connecting the ANALOG-ENAB input (pin 5) to the Digital ground (pin 4).

When analog programming is enabled, the front panel VOLTAGE and CURRENT controls are disconnected and have no effect on the output.

You also cannot program the output using any other interface (i.e. GPIB, LAN, USB, web browser).

Control the Output Voltage and Current with Voltage Sources

Analog programming of the output voltage and current can be accomplished by connecting positive voltage sources to the VPROG and IPROG pins as shown.

Depending on the reference voltage selection, a voltage source variable from 0 to + 5 V or 0 to + 10 V produces an output current or output voltage setting that is proportional to the zero to full-scale rating of the power supply.

Note: Using a 0 to 5 V voltage source halves the effective resolution compared to using a 0 to 10 V voltage source.

Control the Output Voltage and Current with Potentiometers

Analog programming of the output can be accomplished by connecting external potentiometers to the VPROG and IPROG pins as shown. This is similar to the function of the front panel voltage and current knobs.

The potentiometers must be rated at 10 kΩ. Connect the VREF pin to one end of the potentiometers. Connect the wipers to the VPROG and IPROG pins.

Note: Using a 5 V VREF halves the effective resolution of the potentiometers as compared to using a 10 V VREF.

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2 Operating Information

Output Turn On Control in Analog Mode

With Firmware Revision B.02.04, the following SCPI commands are available while in analog mode: *RCL, *SAV, OUTPut[:STATe], and OUTPut:PON:STATe.

With this firmware update, you can enable the Analog control inputs as previously described, and then if desired, use the RCL0 functionality to turn on the output at power-on. The INHIBIT pin can then be programmed to subsequently act as an on/off control signal. The OVP and OCP settings can also be recalled in analog mode as part of the saved output state.

Use the following commands to configure the saved operating state. These commands only need to be sent once, since the *SAV causes the state to be saved in nonvolatile memory.

Turn the output on:

Front Panel Menu SCPI Command

Press the On/Off key. To turn the output on: OUTP ON

Set the OVP and OCP protection.

Front Panel Menu SCPI Command

Select Protect\OVP Enter the value in the OVP level box. Then press Select.

Select Protect\OCP Check Enable OCP. Then press Select.

To set the OVP level to 55 volts:

VOLT:PROT 55

To enable OCP:

CURR:PROT:STAT ON

Saves the above settings to State 0, so they can be recalled at power-on while in Analog Control mode.

Front Panel Menu SCPI Command

Select States\SaveRecall.

In the SaveRecall field, enter location 0. Then press Select. Select Save to save the state.

To save a state in location 0: *SAV 0

Use the following commands to configure user preferences that are always stored in nonvolatile memory. These commands only need to be sent once, and do not require a *SAV.

Configure the unit to recall State 0 at power-on.

Front Panel Menu SCPI Command

Select States\PowerOn. Select Recall State 0. Then press Select.

OUTP:PON:STAT RCL0

Program the INHIBIT input (pin 13) to directly control the output with no latching action.

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2 Operating Information

Front Panel Menu SCPI Command

Not available

OUTP:INH:MODE LIVE

Set the INHIBIT input (pin 13) to the desired polarity. For example:

Front Panel Menu SCPI Command

Not available

DIG:PIN13:POL NEG

Once all of the above commands have been sent one time, the unit will always power on in a state where it can be controlled using its analog programming signals, with no SCPI or front panel programming required.

Analog Monitoring of Voltage and Current

Output voltage and currents can be monitored and measured by connecting a standard multimeter to the VMON and IMON pins as shown.

Depending on the reference voltage selection, a voltage reading from 0 to + 5 V or 0 to + 10 V corresponds to the zero to full-scale voltage or current output of the power supply.

The output monitoring pins are always available. You do not need to enable analog programming to read the output voltage and current.

Monitoring Instrument Status

OT (over-temperature), CV (constant voltage), and Fault status can be monitored by connecting a standard multimeter to the appropriate status pins as shown.

For OT, a reading >4 V indicates the status condition is true. A reading <1 V indicates the status is false. For CV, a reading >4 V indicates a CV status condition.

For Fault, you can configure the polarity as positive or negative. For positive, a reading >4 V indicates the status condition is true. For negative, a reading <1 V indicates the status condition is true. When true, one of the following fault conditions has occurred:

over-voltage (OV) over-current (OC) over-temperature (OT) power-fail (PF) master-slave protect (MSP) inhibit signal (INH)

Query the Questionable status register to determine which fault condition occurred.

The status monitoring pins are always available. You do not need to enable analog programming to monitor output status.

76 Keysight N8900 Series Operating and Service Guide

Output On/Off Control

In a master/slave configuration, only the master unit's Inhibit input and Fault output are used. On the master unit these signals control the entire master/slave system. Do not connect the Inhibit inputs and Fault outputs on any of the slave units.

The INHIBIT input (pin 13) can be used as a remote output control. This lets an external input signal control the output state of the instrument. This input is level triggered. Pin 4 is the common for pin 13. Use a low resistance contact such as a switch, relay, or transistor to connect the pin to digital ground (DGND).

You can configure the polarity of this pin as positive or negative. For the wiring shown, configuring negative polarity will cause the output to be inhibited when the switch is closed.

The following functions can be programmed:

LATChing - a true signal on the Inhibit input causes the output state to latch OFF. The output remains disabled until the Inhibit input is returned to logic-false and the latched INH status bit is cleared by sending the OUTPut:PROTection:CLEar command or a protection clear command from the front panel.

2 Operating Information

LIVE - allows the enabled output to follow the state of the Inhibit input. When the Inhibit input is true, the output is disabled. When the Inhibit input is false, the output is re-enabled.

OFF - The Inhibit input is ignored.

The inhibit pin is always available. You do not need to enable analog programming to use the inhibit input.

To specify the inhibit function for pin 13:

Front Panel Menu SCPI Command

Not available

To specify Negative polarity for pin 13:

Front Panel Menu SCPI Command

Not available

OUTP:INH:MODE <LATC|LIVE|OFF>

DIG:PIN13:POL NEG

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2 Operating Information

Fault/Inhibit System Protection for Multiple Supplies

Live mode is not recommended when connecting the Fault/inhibit system protection to multiple units. Live mode may result in unpredictable behavior of the units. Use Latching mode instead. The multiple-unit connections shown below do not apply in a

master/slave configuration.

When the Fault outputs and Inhibit inputs of several instruments are daisy-chained, an internal fault condition in one of the units will disable all outputs without intervention by either the controller or external circuitry.

Note that when using the Fault/Inhibit signals in this manner, both signals must be set to the same polarity.

To specify the fault function for pin 13:

Front Panel Menu SCPI Command

Not available

OUTP:INH:MODE <LATC|OFF>

(do not use LIVE mode)

To specify either Positive or Negative polarity for pins 13 and 14:

Front Panel Menu SCPI Command

Not available To specify the polarity for pins 13 and 14:

DIG:PIN<13|14>:POL <POS|NEG>

You can also connect one of the Inhibit inputs to a manual switch or external control signal that will short the Inhibit pin to common whenever it is necessary to disable all outputs (see Output On/Off Control). Negative polarity must be programmed for all pins in this case.

Clearing the Fault Condition for Multiple Supplies

To restore all instruments to a normal operating condition when a fault condition occurs in a daisychained system protection configuration, two fault conditions must be removed:

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2 Operating Information

The initial protection fault or external Inhibit signal.

The subsequent daisy-chained fault signal (which is sourced by the Inhibit signal).

When the the operating mode of the Inhibit input is Latched, turn off the Inhibit input on ALL units individually. To re-enable the chain, re-program the Inhibit input on each unit to Latched mode.

Extending Fault/Inhibit Protection to Other Keysight Power Supplies

The following diagram illustrates how to connect other Keysight power supplies to the Fault/Inhibit scheme used in the Keysight N8900 series power supplies.

Other Keysight power supply families use a similar fault inhibit protection scheme as the N8900 series power supplies. For these other power supplies, the Fault/Inhibit wiring is slightly different because of the addition of an extra signal return pin for the Fault signal.

Pin Descriptions and Characteristics

The connections to the other Keysight power supplies are illustrated by the red wires.

Clearing the Fault condition is the same as previously described .

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2 Operating Information

Pin Descriptions

Pin Name Type Description

1 VPROG Analog in Programs output voltage. Only active when ANALOG-ENAB is low.

This pin is not active on Models N8737APV and N8957APV.

2 IPROG Analog in Programs output current. Only active when ANALOG-ENAB is

low. This pin is not active on Models N8737APV and N8957APV.

3 VREF Analog out Voltage reference. Can be connected to VPROG or IPROG directly

to program full scale, or through potentiometers to adjust programmed values.

4 DGND Ground Ground for digital inputs and outputs.

5 ANALOG-ENAB Digital in Enables analog programming of the output when low.

6 OT Digital out Over-temperature status indicator. High when OT is tripped.

7, 8 Not used

9 VMON Analog out Voltage monitor signal.

10 IMON Analog out Current monitor signal.

11 AGND Ground Ground for analog inputs and outputs.

12 Not used

13 INHIBIT Digital in Inhibits (turns off) the output. Can be configured as positive or

negative polarity.

14 FAULT Digital out OV, OC, OT, PF, MSP, or INH status indicator. Can be configured

as positive or negative polarity.

15 CV Digital out Constant voltage status indicator. High when in CV mode.

Pin Characteristics

Analog Input (pin 1, 2) Full scale voltage: 5 V or 10 V, depending on the

Menu:\System\IO\Analog setting. Input resistance: 150 kΩ. These pins are not active on Models N8737APV and N8957APV.

Analog Output (pin 3, 9, 10) Full scale voltage: 5 V or 10 V, depending on the

Menu:\System\IO\Analog setting.

Digital Inputs (pin 5, 13) Drive with relay to ground or open-collector driver.

Open-circuit voltage: approximately 6.5 V. Driver current sink requirement: < 0.4 V @ 3 mA

Digital Outputs (pin 6, 14, 15) High state: 4.74 kΩ pull-up to approximately 10 V.

Low state sink capability: < 0.4 V @ 5 mA

Voltage Reference Voltage: Fixed 5 V or 10 V, depending on the

Menu:\System\IO\Analog setting.

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2 Operating Information

System-Related Operations

Instrument Identification

Instrument State Storage

Front Panel Display

Password Protection

Instrument Identification

You can query the model number, serial number, options, and firmware revision. SCPI commands let you return information with the *IDN? and *OPT? queries.

Front Panel Menu SCPI Command

Select System\About\Frame. To return model number, serial number,

and firmware revision: *IDN?

To return the installed options: *OPT?

Instrument State Storage

The power supply has ten storage locations in non-volatile memory to store instrument states. The locations are numbered 0 through 9. Any state previously stored in the same location will be overwritten.

Front Panel Menu SCPI Command

Select States\SaveRecall.

In the SaveRecall field, enter a location from 0 to 9. Then press Select. Select Save to save the state or Recall to recall a state.

Specifying a power-on state

When shipped from the factory, the power supply is configured to automatically recall the reset (*RST) settings at power-on. However, you can configure the power supply to recall the settings you have stored in memory location 0 (RCL0) at power-on.

Front Panel Menu SCPI Command

To save a state in location 1: *SAV 1

To recall a state from location 1: *RCL 1

Select States\PowerOn.

Select Recall State 0. Then press Select.

OUTP:PON:STAT RCL0

SHOCK HAZARD If the output is enabled when an instrument state is saved to location 0 (zero), the output will automatically be enabled at turn-on if the power-on state is set to recall location zero (RCL0).

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2 Operating Information

Front Panel Display

The power supply has a front panel screen saver that significantly increases the life of the LCD display by turning it off during periods of inactivity. The delay can be set from 30 to 999 minutes in 1 minute increments. As shipped from the factory, the screen saver comes on one hour after activity on the front panel or interface has ceased.

When the screen saver is active, the front panel display turns off, and the LED next to the Line switch changes from green to amber. To restore the front panel display, simply press one of the front panel keys. The first action of the key turns the display on. After that the key reverts to its normal function.

If the Wake on I/O function is selected, the display is restored whenever there is activity on the remote interface. This also resets the timer on the screen saver. As shipped, Wake on I/O is active.

Front Panel Menu SCPI Command

Select System\Preferences\Display

Enable or disable the screen saver by checking or unchecking the Screen Saver checkbox. Then press Select.

Enter a value in minutes in the Saver Delay field to specify the time when the screen saver will activate.

Check Wake on I/O to activate the display with I/O bus activity.

Not available

Password Protection

You can password-protect all functions located in the Admin menu. These include: instrument calibration, interface access, non-volatile memory reset, firmware update, password updates.

As shipped the Admin password is 0 (zero). This means that you do not have to enter a password. Simply select System\Admin\Login and press Enter. To password-protect the Admin menu:

Front Panel Menu SCPI Command

Select System\Admin\Password

The password must be numeric, and up to 15 digits long. Then press Select.

Log out of the Admin menu to activate the password. You can now only enter the Admin menu by providing the right password. Enter the password in the Password field.

Enter calibration mode using the original password

CAL:STAT ON, <password>

To change the password:

CAL:PASS <password>

To exit calibration mode and activate the password:

CAL:STAT OFF

If the password is lost, access can be restored by setting an internal switch to reset the password to 0. If the message “Locked out by internal switch setting” or “Calibration is inhibited by switch setting” appears, the internal switch is set to prevent the password from being changed. Refer to Calibration

Switches for more information.

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2 Operating Information

Operating Mode Tutorial

Voltage Regulation

Current Regulation

Power Regulation

Voltage Regulation

Voltage regulation is also known as constant voltage mode (CV).

In CV mode, the DC output voltage of the power supply is held constant at its voltage setting, unless the output current or the output power reaches the current limit setting or the power limit. In both cases the device will automatically change to constant current (CC) or constant power (CP) operation. The output voltage is no longer held constant, and will sink to a value according to Ohm’s law.

When the power supply is operating in constant voltage mode, the front panel CV status indicator is displayed. The CV status condition can also be read using SCPI commands and by monitoring the CV status pin on the Analog connector.

The figure below shows an operating locus that is defined by voltage setting, current setting, and power limit of the unit.The load resistance determines the point on that locus at which the power supply actually operates. The line representing Load resistance A, the highest load resistance shown on the figure, crosses the operating locus at point 1. Point 1 is on the part of the operating locus defined by the voltage setting, so the power supply operates in CV mode.

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2 Operating Information

Current Regulation

Current regulation is also known as current limiting or constant current mode (CC).

In CC mode, the DC output current is held constant by the power supply when the output current reaches the current limit setting. The power supply then switches from CV to CC mode. If, however, the power consumption reaches the set maximum power value, the device will switch automatically to power limit (CP) where Vout X Iout = Plimit.

When the power supply is operating in constant current mode, the front panel CC status indicator is displayed. The CC status condition can also be read by using SCPI commands.

In the figure above, the line representing load resistance C, the lowest load resistance shown on the graph, crosses the operating locus at point 3. Point 3 is on the part of the operating locus defined by the current setting, so the power supply operates in CC mode.

Power Regulation

Power regulation is also known as power limiting or constant power mode (CP).

In CP mode, the DC output power is limited at the unit's maximum rated power. Power limiting operates according to the auto-ranging principle such that at lower output voltages higher current flows, and at higher output voltages lower current flows. This maintains the output power within the power rating of the unit supply.

When the power supply is at the constant power limit, the front panel CP status indicator is displayed. The CP status condition can also be read by by using SCPI commands.

The power supply can operate at the power limit without being damaged. However, the power supply is not guaranteed to meet specifications when operating in power limit mode. Output ripple may increase and neither output voltage or current is regulated.

In the figure above, the line representing load resistance B crosses the operating locus at point 2. Point 2 is on the output power boundary of the unit, so the power supply operates in CP mode. Press the Meter key to display the power (W) being supplied to the output.

Refer to Autoranging Characteristic for the power limit indices of the various N8900A models.

84 Keysight N8900 Series Operating and Service Guide

SAS Operation

Introduction

Programming Curve Parameters

Programming Table Parameters

Programming Multiple Tables

Programming Scale Factors

Exponential Model Equations

Solar Array Simulator operation only applies to Models N8737APV and N8957APV. These models can operate as a solar array simulator. All capabilities of the standard "A" models except analog programming are available in the "PV" models.

The SAS Curve Generator software is a free application that simplifies programming the PV models. It is available at www.keysight.com/find/N8900APVsoftware.

2 Operating Information

Introduction

The Models N8737APV and N8957APV operate as a solar array simulator only when the SAS:MODE command specifies either curve or table mode. In curve mode, an SAS characteristic is created from four input parameters:

Imp – the current at the maximum power point Isc – the short-circuit current Vmp - the voltage at the maximum power point Voc – the open-circuit voltage

When programming a new SAS curve, it is best to send all of the curve parameters on the same line. With this method, the curve parameters can be sent in any order, and the instrument will determine whether all four parameters are within acceptable limits. Any parameter not programmed will retain the value of the previously programmed curve.

If the curve parameters are sent individually, an error can occur if the parameter value is outside the allowable curve characteristic determined by the three remaining parameters.

In table mode, an SAS characteristic is created from up to 1024 points programmed by the user.

You can specify solar array simulator operation as follows:

Front Panel Menu SCPI Command

Select Output\Mode.

Specify either Curve or Table mode. Then press Select.

l The command is accepted only when the output is off, otherwise an error will be generated.

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To specify Curve mode: SAS:MODE CURV

To specify Table mode: SAS:MODE TABL

2 Operating Information

Programming the Curve Parameters

In Curve mode, the output has an I-V characteristic that follows an exponential model of a solar array. Refer to SAS Equations, where the exponential model equations are listed. The exponential model is specified using the four parameters: Imp, Isc, Vmp, and Voc. These can be programmed individually, but when programminga new curve, it is best to send all of the curve parameters on the same line (see SAS:CURV commands).

Front Panel Menu SCPI Command

Select Output\SAS\Curve

In the dialog, enter a value for each of the four I-V curve parameters. Then press Select.

Specify the maximum power point current:

SAS:CURV:IMP <value>

Specify the short-circuit current:

SAS:CURV:ISC <value>

Specify the maximum power point voltage:

SAS:CURV:VMP <value>

Specify the open-circuit voltage:

SAS:CURV:VOC <value>

Programming the Table Parameters

With PV firmware rev A.02.04 and up you can load up to two tables into the SAS instrument. If no table number is specified [1 or 2], the command defaults to using TABLe1 for backwards compatibility.

In this mode, a table of I-V points specifies the curve. A table can be programmed with a maximum of 1024 I-V points per table. The table lists must satisfy the following requirements.

For both current and voltage lists:

l The number of points in each list can range from 3 to 1024.

l Both lists must contain the same number of points.

For the voltage list:

l The first value must be 0 (a range of ±15 mV is allowed).

l The point values must be strictly monotonically increasing. Adjacent values are not permitted to be

equal.

For the current list:

l The point values must be monotonically decreasing. Adjacent values are permitted to be equal.

l The last value must be 0 (a range of ±0.3 mA is allowed).

Use the following commands to program the table parameters into IO memory:

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2 Operating Information

Front Panel Menu SCPI Command

Not available To program a current table list:

MEM:TABL[1|2]:CURR <current>{,<current>}

To program a voltage table list:

MEM:TABL[1|2]:VOLT <voltage>{,<voltage>}

Table values are not saved aspart of the instrument state.

Use the following command to activate the table, which runs the curve using the table points.

Front Panel Menu SCPI Command

Not available To activate the current and voltage tables:

SAS:TABL[1|2]:ACT

l If the points do not represent a valid data set, an error will be generated.

Use the following commands to query the number of data points in the current and voltage tables.

Front Panel Menu SCPI Command

Not available To query the current and voltage table points:

MEM:TABL[1|2]:CURR:POIN? MEM:TABL[1|2]:VOLT:POIN?

Programming Multiple Tables

As previously discussed, and shown in the top part of the following diagram, MEMory:TABLe commands load voltage or current data into the IO memory of the instrument. In the simplest mode of operation, once the table data is in IO memory, the SAS:TABLe:ACTivate command moves (updates) the data into the processor memory and selects the table.

With PV firmware A.02.04 and up, you can load table data into processor memory from two tables and then instantly switch the power stage from one to the other. This is useful if you quickly need to switch the output from one table to another to generate different curve characteristics. This required the addition of two SCPI commands: SAS:TABLe[1|2]:UPDate and SAS:TABLe:SELect.

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2 Operating Information

It is possible to use the SAS:TABLe:ACTivate command to perform the same function as the SAS:TABLe:UPDate and SAS:TABLe:SELect commands. However, because it takes a considerable amount of time to load data into processor memory, you cannot instantly switch from one table to another using only the SAS:TABLe:ACTivate command.

To avoid this data-loading time constraint, you can use the SAS:TABLe[1|2]:UPDate command to load the data for both tables from IO memory into processor memory ahead of time. This will overwrite any table data that has been previously loaded into processor memory with the SAS:TABLe:ACTivate command.

Front Panel Menu SCPI Command

Not available To update the table in processor memory:

SAS:TABL[1|2]:UPD

l You can update both tables in processor memory.

l You cannot update a table that is presently selected.

l The update command only updates the table. It does not select the table.

Once loaded into processor memory, you can then use the SAS:TABLe:SELect command to run the table. You can also use this command to switch between two tables in processor memory without turning off the output.

Front Panel Menu SCPI Command

Not available To select tables in processor memory:

MEM:TABL:SEL 1

to switch and run table 2

MEM:TABL:SEL 1

Programming Scale Factors

You can program scale factors for the current and voltage SAS curves.

Front Panel Menu SCPI Command

Select Output\SAS\Scale.

Enter a scale factor in percent for the current and/or voltage tables. Then press Select.

To program current and voltage scale factors:

SAS:SCAL:CURR <percent> SAS:SCAL:VOLT <percent>

l This function is active in both Curve and Table modes. All of the voltages and currents on the SAS

curve are multiplied by these scale factors.

l The scale factor settings take effect immediately without turning off the output.

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2 Operating Information

SAS Exponential Model Equations

The following equations describe the solar array simulator exponential model using the parameters Rs, N, and a, which are defined as functions of the four input parameters.

Note that these equations tend to be most accurate for curves that are somewhat rectangular.

Figure A indicates the potential range of Pmp error percent due to the modeling equation. The x-axis parameter is (Voc/Vmp) * (Isc/Imp), which is a measure of the rectangularity of the simulator curve, with values near 1 being highly rectangular. The y-axis is a measure of the possible error of the curve algorithm equation at the peak power point as defined by the following equation:

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2 Operating Information

Figure A. Range of Pmp Error Due to Modeling Equation

The exponential model is described in the paper: Britton, Lunscher, and Tanju, "A 9 KW HighPerformance Solar Array Simulator", Proceedings of the European Space Power Conference, August 1993 (ESA WPP-054, August 1993)

The potential error between the equation’s actual peak power and the expected peak power (Vmp * Imp) will increase as the curves become less rectangular.

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Keysight N8900 Series Operating and Service Guide

3 SCPI Programming Reference

Related Information

Introduction to the SCPI Language

Commands by Subsystem

Command Quick Reference

Reset State (*RST)

SCPI Error Messages

Compatibility Commands

3 SCPI Programming Reference

Related Information

IO Libraries and Instrument Drivers

The Keysight IO Libraries Suite software is provided on the Keysight Automation Ready CD-ROM provided with your instrument. Installation instructions are provided on the CD-ROM.

For detailed information about interface connections, refer to the documentation included with the Keysight IO Libraries Suite. Or you can download the guide from the Web at

www.keysight.com/find/connectivity.

You can also download the Keysight IO Libraries Suite software, along with IVI-COM and LabVIEW drivers from the Keysight Developer Network at www.keysight.com/find/adn.

N8900 Series Documentation

You can download the latest version of this document at www.keysight.com/find/n8900-doc.

Web Interface

The N8900 series provides a Web interface that is built into the instrument. You can use this interface over LAN for remote access and control of the instrument via a Web browser. See Using the Web

Interface for details.

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Introduction to the SCPI Language

Command Types

Keywords

Queries

Command Separators and Terminators

Syntax Conventions

Parameter Types

Device Clear

Command Types

This instrument complies with the rules and conventions of the present SCPI version (see

SYSTem:VERSion?).

SCPI (Standard Commands for Programmable Instruments) is an ASCII-based instrument command language designed for test and measurement instruments. SCPI has two types of commands, common and subsystem.

Subsystem Commands

Subsystem commands perform specific instrument functions. They are comprised of alphabetically arranged commands that extend one or more levels below the root in a hierarchical structure, also known as a tree system. In this structure, associated commands are grouped together under a common node or root, thus forming subsystems. A portion of the OUTPut subsystem is shown below to illustrate the tree system. Note that some [optional] commands have been included for clarity.

OUTPut

[:STATe] OFF|0|ON|1 :PON :STATe RST|RCL0 :PROTection :CLEar

IEEE-488.2 Common Commands

The IEEE-488.2 standard defines a set of common commands that perform functions such as reset, self-test, and status operations. Common commands always begin with an asterisk ( * ), are three characters in length, and may include one or more parameters. The command keyword is separated from the first parameter by a blank space. Use a semicolon ( ; ) to separate multiple commands as shown below:

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Keywords

Keywords, also referred to as headers, are instructions recognized by the instrument. Common commands are also keywords.

OUTPut is the root keyword, PROTection is a second-level keyword, CLEar is a third-level keyword. Colons ( : ) separate the keyword levels.

The command syntax shows most commands (and some parameters) as amixture of upper- and lower-case letters. The upper-case letters indicate the abbreviated spelling for the command. For shorter program lines, you can send the abbreviated form. For better program readability, you can send the long form.

In the above examples, OUTP and OUTPUT are both acceptable forms. You can use upper- or lowercase letters. Therefore, OUTPUT, outp, and Outp are all acceptable. Other forms such as OUT, are not valid and will generate an error.

Queries

Following a keyword with a question mark (?) turns it into a query (Example: VOLTage?, VOLTage:TRIGgered?). If a query contains parameters, place the query indicator at the end of the last keyword, before the parameters. Insert a space between the query indicator and the first parameter.

You can query the programmed value of most parameters. For example, you can query the voltage setting by sending:

VOLTage?

You can also query the minimum or maximum allowable voltage settings as follows:

VOLTage? MIN VOLTage? MAX

You must read back all the results of a query before sending another command to the instrument. Otherwise, a Query Interrupted error will occur and the unreturned data will be lost.

Command Separators and Terminators

Separators

Colons ( : ) separate keyword levels. Blank spaces must be used to separate command parameters from their corresponding keyword. Note the space between STATe and the *RST parameter.

OUTPut:PON:STATe RST

Semicolons ( ; )separate commands within the same subsystem. This lets you send several subsystem commands within the same message string. For example, sending the following command string:

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OUTPut:STATe ON;PON:STATe RST

is the same as sending the following commands:

OUTPut ON OUTPut:PON:STATe RST

Note that the semicolon follows the implied path of the hierarchical tree structure. In the above example, the optional :STATe keyword must follow the OUTput keyword to place the command parser at the second level in the hierarchy. This allows the use of the PON keyword after the semicolon, since PON is a second-level keyword.

You can also combine commands of different subsystems within the same message string. In this case, you must use a colon to return the command parser to the root level in order to access another subsystem. For example, you could clear the output protection and check the status of the Operation Condition register in one message by using a root specifier as follows:

OUTPut:PROTection:CLEar;:STATus:OPERation:CONDition?

Note the use of the colon after the semicolon in order to return the command parser to the root.

Terminators

A command string sent to the instrument must terminate with a new line (<NL>) character. The IEEE488 EOI (End-Or-Identify) message is interpreted as a <NL> character and can be used to terminate a command string in place of an <NL>. A carriage return followed by a new line (<CR><NL>) is also accepted. Command string termination will always reset the current SCPI command path to the root level.

Syntax Conventions

Triangle brackets ( < > ) indicate that you must specify a value for the enclosed parameter. For example, in the VOLTage <value> command syntax, the <value> parameter is enclosed in triangle brackets. The brackets are not sent with the command string. You must specify a value for the parameter (Example: "VOLTage 50V") unless you select another option shown in the syntax (Example: "VOLTage MAX").

A vertical bar ( | ) separatesmultiple parameter choices for a given command string. For example, RST|RCL0 in the OUTPut:PON:STATe command indicates that you can specify "RST" or "RCL0". The bar is not sent with the command string.

Square brackets ( [ ]) enclose some syntax elements - nodes and parameters for example. This indicates that the element is optional and can be omitted. Thebrackets are not sent with the command string. Any keyword enclosed in brackets is optional and can be omitted. However, if you are combining several commands within the same message string as previously described, you must include the optional commands to place the command parser at the correct level in the hierarchy.

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Parameter Types

The SCPI language defines several data formats to be used in commands and queries.

Numeric Parameters

Commands that require numeric parameters will accept all commonly used decimal representations of numbers including optional signs, decimal points, and scientific notation. If a command accepts only certain specific values, the instrument will automatically round the input numeric parameters to the accepted values. The following command requires a numeric parameter for the voltage value:

[SOURce:]VOLTage 50V|MIN|MAX

Note that special values for numeric parameters such as MINimum and MAXimum are also accepted. Instead of selecting a specific value for the voltage parameter, you can substitute MIN to set the voltage to its minimum allowable value, MAX to set it to its maximum allowable value.

You can also send engineering unit suffixes with numeric parameters (e.g., V for volts, A for amperes, W for Watts). All parameters values are in base units.

Discrete Parameters

Discrete parameters are used to program settings that have a limited number of values (like IMMediate, EXTernal, or BUS). They may have a short form and a long form just like command keywords. You can use upper- or lower-case letters. Query responses will always return the short form in all upper-case letters. The following command requires a discrete parameter for the display settings:

VOLTage:MODE FIXed|STEP

Boolean Parameters

Boolean parameters represent a single binary condition that is either true or false. For a false condition, the instrument will accept "OFF" or "0". For a true condition, the instrument will accept "ON" or "1". When you query a Boolean setting, the instrument will always return "0" or "1". The following command requires a Boolean parameter:

OUTput OFF|0|ON|1

ASCII String Parameters

String parameters can contain virtually any set of ASCII characters. A string must begin and end with matching quotes; either with a single quote or a double quote. You can include the quote delimiter as part of the string by typing it twice without any characters in between. The following command uses a string parameter:

CALibrate:DATE "12/12/12"

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Device Clear

Device Clear is an IEEE-488 low-level bus message that you can use to return the instrument to a responsive state. Different programming languages and IEEE-488 interface cards provide access to this capability through their own unique commands. The status registers, theerror queue, and all configuration states are left unchanged when aDevice Clear message is received.

Device Clear performs the following actions:

l If a measurement is in progress, it isaborted.

l The instrument returns to the trigger idle state.

l The instrument's input and output buffers are cleared.

l The instrument is prepared to accept a new command string.

The ABORt command is the recommended method to terminate an instrument operation.

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3 SCPI Programming Reference

Commands by Subsystem

Subsystem

Calibrate

Current

Digital

Display

Measure

Output

SASimulator - applies to N8937APV and N8957APV models only

Status

System

Trigger

Voltage

Common Commands

IEEE-488.2 common commands are included along with the Status, System, and Trigger subsystem commands.

Additional Commands

Compatibility

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Calibrate Commands

Calibrate commands calibrate the instrument.

Read the calibration section before calibrating. Improper calibration can reduce accuracy and reliability.

CALibrate:COUNt?

Returns the number of times the unit has been calibrated. The count is incremented whenever the calibration (including the date) is saved, the administration password is changed, the administration password is reset using the internal cal switch, or the instrument firmware is updated.

Parameter Typical Return

(none) The calibration count

Return the calibration count: CAL:COUN?

CALibrate:CURRent[:LEVel] [<value>]

Calibrates the current programming and measurement. The optional value parameter selects the range to calibrate. This is for compatibility with the N6700 series modular power system.

Parameter Typical Return

Optional - the maximum value of the range.

Calibrates the current of the 100 A range: CAL:CURR 100

(none)

CALibrate:DATA <value>

Enters the calibration value read by the external meter. You must first select a calibration level for the value being entered. Data values are expressed in base units - either volts or amperes, depending on which function is being calibrated.

Parameter Typical Return

Numeric value (none)

Specify calibration value 0.0237: CAL:DATA 2.37E-2

CALibrate:DATE <"date"> CALibrate:DATE?

Enters the calibration date in nonvolatile memory. Enter any ASCII string up to 10 characters. The query returns the date.

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Parameter Typical Return

<"date">String program data. Enclose string parameters in single or double quotes.

Enters the calibration date: CAL:DATE "12/12/12"

Date of last calibration

CALibrate:LEVel P1|P2|P3|P4

Advances to the next level in the calibration. P1 is the first level; P2 the second, P3 the third, and P4 the fourth.

Parameter Typical Return

P1|P2|P3|P4 (none)

Selects the first calibration point: CAL:LEV P1

l Some calibration sequences may require some settling time after sending CAL:LEV but before reading

the data from the DVM and sending CAL:DATA.

CALibrate:PASSword <password>

Sets a numeric password to prevent unauthorized calibration.

Parameter Typical Return

<password>a numeric value up to 15 digits (none)

Set a new password to a value of 1234: CAL:PASS 1234

l If the password is set to 0, password protection is removed and the ability to enter calibration mode is

unrestricted. The factory setting is 0 (zero).

l To change the password: unsecure calibration memory with old code, then set the new code.

If you forget your password, refer to the calibration section.

l This setting is non-volatile; it will not be changed by power cycling or *RST.

CALibrate:SAVE

Saves the calibration constants in non-volatile memory. Do this at the end of the calibration to avoid losing changes.

Parameter Typical Return

(none) (none)

Store cal constants in non-volatile memory: CAL:SAVE

100 Keysight N8900 Series Operating and Service Guide

Agilent N8932A Users Guide N89000 Series Power Supplies

Specifications and Main Features

Frequently Asked Questions

User Manual

1 Preliminary Information

Documentation and Firmware Revisions

Contacting Keysight Technologies

Legal and Safety Information

Legal Notices

Safety Symbols

Safety Notices

Models and Options

Model Ratings

Accsssories/Options

Specifications and Characteristics

Specifications

Supplemental Characteristics 5 kW

Supplemental Characteristics 10 kW

Supplemental Characteristics 15 kW

Common Characteristics

Autoranging Characteristics

Dimension Diagrams

2 Operating Information

Introduction to the Instrument

Front Panel at a Glance

Front Panel Display at a Glance

Front Panel Keys at a Glance

Rear Panel at a Glance

Front Panel Menu

Installing the Instrument

Before Installation or Use

AC Mains Connections

Single Unit Connections

Multiple Unit Connections

External Control Signal Connections (Analog)

Interface Connections

Getting Started

Turn the Unit On

Set the Output Voltage

Set the Output Current

Set the Over-Voltage Protection

Enable the Output

Use the Built-in Help System

Remote Interface Configuration

USB Configuration

GPIB Configuration

LAN Configuration

Modifying the LAN Settings

Using the Web Interface

Using Telnet

Using Sockets

Interface Lockout

Using the Power Supply

Programming the Output

Programming Output Protection

Programming Output Steps

Making Measurements

Parallel Operation

External Control Signal Programming

System-Related Operations

Operating Mode Tutorial

SAS Operation

3 SCPI Programming Reference

Related Information

Introduction to the SCPI Language

Command Types

Keywords

Queries

Command Separators and Terminators

Syntax Conventions

Parameter Types

Device Clear

Commands by Subsystem

Subsystem

Common Commands

Additional Commands

Calibrate Commands