AMETEK SFA Series User Manual

SFA Series DC

Power Supplies

Operation Manual

M550292-01 Rev G www.programmablepower.com

About AMETEK

AMETEK Programmable Power, Inc., a Division of AMETEK, Inc., is a global leader in the design
and manufacture of precision, programmable power supplies for R&D, test and measurement,
process control, power bus simulation and power conditioning applications across diverse
industrial segments. From bench top supplies to rack-mounted industrial power subsystems,
AMETEK Programmable Power is the proud manufacturer of Elgar, Sorensen, California
Instruments and Power Ten brand power supplies.

AMETEK, Inc. is a leading global manufacturer of electronic instruments and electromec hanical
devices with annualized sales of $2.5 billion. The Company has over 11,000 colleagues working
at more than 80 manufacturing facilities and more than 80 sales and service centers in the United
States and around the world.

Trademarks

AMETEK is a registered trademark of AMETEK, Inc.
Other trademarks, registered trademarks, and product names are the property of their respective
owners and are used herein for identification purposes only.

Notice of Copyright

SFA Series DC Power Supplies Operation Manual

Inc. All rights reserved.

© 2004-2008 AMETEK Programmable Power,

Exclusion for Documentation

UNLESS SPECIFICALLY AGREED TO IN WRITING, AMETEK PROGRAMMABLE POWER, INC.
(“AMETEK”):

(a) MAKES NO WARRANTY AS TO THE ACCURACY, SUFFICIENCY OR SUITABILITY OF ANY

TECHNICAL OR OTHER INFORMATION PROVIDED IN ITS MANUALS OR OTHER
DOCUMENTATION.

(b) ASSUMES NO RESPONSIBILITY OR LIABILITY FOR LOSSES, DAMAGES, COSTS OR

EXPENSES, WHETHER SPECIAL, DIRECT, INDIRECT, CONSEQUENTIAL OR INCIDENTAL,
WHICH MIGHT ARISE OUT OF THE USE OF SUCH INFORMATION. THE USE OF ANY SUCH
INFORMATION WILL BE ENTIRELY AT THE USER’S RISK, AND

(c) REMINDS YOU THAT IF THIS MANUAL IS IN ANY LANGUAGE OTHER THAN ENGLISH,

ALTHOUGH STEPS HAVE BEEN TAKEN TO MAINTAIN THE ACCURA CY OF THE
TRANSLATION, THE ACCURACY CANNOT BE GUARANTEED. APPROVED AMETEK CONTENT
IS CONTAINED WITH THE ENGLISH LANGUAGE VERSION, WHICH IS POSTED AT
WWW.PROGRAMMABLEPOWER.COM.

Date and Revision

June 2009 Revision G

Part Number

M550292-01

Contact Information

Telephone: [phone] (toll free in North America)
858 450 0085 (direct)
Fax: [phone]
Email: [e-mail]
[e-mail]
Web: www.programmablepower.com

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G

G

Important Safety Instructions

Before applying power to the system, verify that your product is configured properly for your
particular application.

WARNIN

WARNIN

Only qualified personnel who deal with attendant hazards in power supplies, are allowed to perform
installation and servicing.

Ensure that the AC power line ground is connected properly to the Power Rack input connector or
chassis. Similarly, other power ground lines including those to application and maintenance
equipment must be grounded properly for both personnel and equipment safety.

Always ensure that facility AC input power is de-energized prior to connecting or disconnecting any
cable.

In normal operation, the operator does not have access to hazardous voltages within the chassis.
However, depending on the user’s application configuration, HIGH VOLTAGES HAZARDOUS TO
HUMAN SAFETY may be normally generated on the output terminals. The customer/use r must
ensure that the output power lines are labeled properly as to the safety hazards and that any
inadvertent contact with hazardous voltages is eliminated.

Guard against risks of electrical shock during open cover checks by not touching any portion of the
electrical circuits. Even when power is off, capacitors may retain an electrical charge. Use safety
glasses during open cover checks to avoid personal injury by any sudden component failure.

Neither AMETEK Programmable Power Inc., San Diego, California, USA, nor any of the subsidiary
sales organizations can accept any responsibility for personnel, material or inconsequential injury,
loss or damage that results from improper use of the equipment and accessories.

Hazardous voltages may be present when covers are removed. Qualified
personnel must use extreme caution when servicing this equipment.
Circuit boards, test points, and output voltages also may be floating above
(below) chassis ground.

The equipment used contains ESD sensitive ports. When installing
equipment, follow ESD Safety Procedures. Electrostatic discharges might
cause damage to the equipment.

SAFETY SYMBOLS

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Product Family: SFA Series DC Power Supplies

Warranty Period: Five Years

WARRANTY TERMS

AMETEK Programmable Power, Inc. (“AMETEK”), provides this written warranty covering the
Product stated above, and if the Buyer discovers and notifies AMETEK in writing of any defect in
material or workmanship within the applicable warranty period stated above, then AMETEK may,
at its option: repair or replace the Product; or issue a credit note for the defective Product; or
provide the Buyer with replacement parts for the Product.

The Buyer will, at its expense, return the defective Product or parts thereof to AMETEK in
accordance with the return procedure specified below. AMETEK will, at its expense, deliver the
repaired or replaced Product or parts to the Buyer. Any warranty of AMETEK will not apply if the
Buyer is in default under the Purchase Order Agreement or where the Product or any part
thereof:

• is damaged by misuse, accident, negligence or failure to maintain the same as

specified or required by AMETEK;

• is damaged by modifications, alterations or attachments thereto which are not

authorized by AMETEK;

• is installed or operated contrary to the instructions of AMETEK;

• is opened, modified or disassembled in any way without AMETEK’s consent; or

• is used in combination with items, articles or materials not authorized by AMETEK.

The Buyer may not assert any claim that the Products are not in conformity with any warranty
until the Buyer has made all payments to AMETEK provided for in the Purchase Order Agreement.

PRODUCT RETURN PROCEDURE

1. Request a Return Material Authorization (RMA) number from the repair facility (must be
done in the country in which it was purchased):

• In the USA, contact the AMETEK Repair Department prior to the return of the

product to AMETEK for repair:
Telephone: [phone], ext. 2295 or ext. 2463 (toll free North America)

858-450-0085, ext. 2295 or ext. 2463 (direct)

• Outside the United States, contact the nearest Authorized Service Center

(ASC). A full listing can be found either through your local distributor or our
website, www.programmablepower.com, by clicking Support and going to the
Service Centers tab.

2. When requesting an RMA, have the following information ready:

• Model number

• Serial number

• Description of the problem

NOTE: Unauthorized returns will not be accepted and will be returned at the shipper’s expense.
NOTE: A returned product found upon inspection by AMETEK, to be in specification is subject to

an evaluation fee and applicable freight charges.

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FCC NOTICE

This equipment has been tested and found to comply with the limits for a Class
A digital device, pursuant to part 15 of the FCC Rules. These limits are
designed to provide reasonable protection against harmful interference when
the equipment is operated in a commercial environment.

This equipment generates, uses, and can radiate radio frequency energy and, if
not installed and used in accordance with the instruction manual, may cause
harmful interference to radio communications. Operation of this equipment in a
residential area is likely to cause harmful interference in which case the user will
be required to correct the interference at his own expense.

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M550292-01 Rev G

ABOUT THIS MANUAL

This manual has been written expressly for the Sorensen SFA Series of power
supplies that have been designed and certified to meet the Low Voltage and
Electromagnetic Compatibility Directive Requirements of the European
Community.

Since the Low Voltage Directive is to ensure the safety of the equipment
operator, universal graphic symbols have been used both on the unit itself and
in this manual to warn the operator of potentially hazardous situations (see
Safety page).

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M550292-01 Rev G

CONTENTS

SECTION 1 OVERVIEW.....................................................................1-1

1.1 GENERAL DESCRIPTION...............................................................1-1

1.2 TECHNICAL SPECIFICATIONS ........................................................1-2

1.2.1 Environmental Characteristics................................................................1-2

1.2.2 Electrical Characteristics........................................................................1-3

1.2.3 SFA Series Voltage and Current Specifications.....................................1-4

1.2.4 Physical Characteristics .........................................................................1-5

SECTION 2 INSTALLATION...............................................................2-1

2.1 INSPECTION................................................................................2-1

2.2 CONTENTS OF SHIPMENT.............................................................2-1

2.3 INPUT/OUTPUT CONNECTIONS .....................................................2-2

2.4 LOCATION AND MOUNTING ...........................................................2-3

2.4.1 6U Chassis Removal from Rack.............................................................2-3

2.5 WIRE SELECTION........................................................................2-6

2.5.1 Wire Size................................................................................................2-6

2.6 LOAD CONSIDERATIONS...............................................................2-8

2.6.1 Inductive Loads ......................................................................................2-8

2.7 OUTLINE DRAWINGS....................................................................2-8

SECTION 3 OPERATION ...................................................................3-1

3.1 CONTROLS AND INDICATORS........................................................3-1

M550292-01 Rev G ix

Contents Sorensen SFA Series

3.1.1 Shaft Lock (Option) ................................................................................3-4

3.2 LOCAL OPERATION ..................................................................... 3-4

3.2.1 Floating and Polarized Output................................................................3-5

3.2.2 Initial Setup.............................................................................................3-5

3.2.3 Current Mode Operation.........................................................................3-6

3.2.4 Overcurrent Protection...........................................................................3-6

3.2.5 Analog Control Connector (J1)...............................................................3-7

3.3 REMOTE CURRENT PROGRAMMING............................................3-11

3.4 REMOTE SENSING ....................................................................3-12

3.5 REMOTE OUTPUT ON/OFF CONTROL .........................................3-14

3.6 REMOTE OVERCURRENT SETPOINT............................................3-15

3.7 REMOTE SHUTDOWN (S/D) .......................................................3-16

3.8 MASTER/SLAVE OPERATION......................................................3-16

3.8.1 Parallel Operation.................................................................................3-16

SECTION 4 VERIFICATION AND CALIBRATION..............................4-1

4.1 INTRODUCTION ...........................................................................4-1

4.1.1 Verification and Calibration Cycle ..........................................................4-1

4.1.2 Preparation.............................................................................................4-1

4.2 STANDARD VERIFICATION AND CALIBRATION PROCEDURE.............. 4-2

4.2.1 Current Mode .........................................................................................4-2

4.2.2 Resistor Programming Current Sources ................................................4-3

4.3 ISOLATED ANALOG (OPTION) VERIFICATION AND CALIBRATION

PROCEDURE...............................................................................4-3

4.3.1 Current Mode .........................................................................................4-4

SECTION 5 MAINTENANCE..............................................................5-1

5.1 INTRODUCTION ...........................................................................5-1

5.2 PREVENTIVE MAINTENANCE.........................................................5-1

5.3 FUSES .......................................................................................5-3

M550292-01 Rev G

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Sorensen SFA Series Contents

LIST OF TABLES

Table 2–1. 5kW to 15kW and 20kW to 30kW Series Input/Output Connectors..................2-4

Table 2–2. Input Connections.............................................................................................2-4

Table 2–3. Output Connections ..........................................................................................2-4

Table 2–4. Minimum Wire Size ...........................................................................................2-6

Table 2–5 Wire Resistance and Voltage Drop....................................................................2-7

Table 2–6 Maximum AC Current Ratings ...........................................................................2-8

Table 2–7 Recommended Lugs..........................................................................................2-8

Table 2–8. Recommended Sense Connector Tools ...........................................................2-8

Table 3–1. ANALOG CONTROL Connector (J1), Designations and Functions................3-10

Table 5–1. Recommended Annual Inspection....................................................................5-2

Table 5–2. Fuse Values......................................................................................................5-3

LIST OF FIGURES

Figure 1-1. Model Number Decoding..................................................................................1-1

Figure 2-1. SFA Series Outline Drawing, 3U Models, 5kW to 15kW...................................2-9

Figure 2–2. SFA Series Outline Drawing, 6U Models, 20kW to 30kW ..............................2-10

Figure 3-1. Front Panel Controls and Indicators (3U model shown)...................................3-1

Figure 3-2. Rear Panel Connectors (3U model shown) ......................................................3-3

Figure 3-3. Shaft Lock.........................................................................................................3-4

Figure 3-4. ANALOG CONTROL Connector (J1) Pin-out...................................................3-8

Figure 3–5. Remote Current Programming Using Resistance..........................................3-11

Figure 3–6. Remote Current Programming Using 0-5 VDC or 0-10 VDC Voltage Source3-12

Figure 3–7. Remote Sensing Operation at the Load * ......................................................3-13

Figure 3–8. Remote On/Off Control by Contact Closure ...................................................3-14

Figure 3–9. Remote On/Off Using Isolated AC or DC Voltage Source.............................3-14

Figure 3–10. Remote On/Off Using Isolated TTL/CMOS Voltage Supply.........................3-15

Figure 3–11. Remote Overcurrent Set Using DC Voltage Source....................................3-15

Figure 3–12. Remote Shutdown Using DC Voltage Source..............................................3-16

Figure 3–13. Master/Slave Connection.............................................................................3-17

Figure 4-1. Precision Current Shunt....................................................................................4-2

Figure 4-2. Potentiometer Locations...................................................................................4-5

M550292-01 Rev G

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M550292-01 Rev G xii

1.1 GENERAL DESCRIPTION

The Sorensen SFA Series power supplies are designed specifically for high
power laser driver applications requiring variable DC current sources with fast
output response times.

SECTION 1

OVERVIEW

A variety of user interfac es are available, ranging from man ual front–panel co ntrol
and standard non–isolated remote analog control, to optional GPIB or isolated
remote analog control.

NOTE: The SFA Series power su pplies a re not designed for series operation and
therefore must not be used as such.

Figure 1-1 decodes the SFA Series model number.

Figure 1-1. Model Number Decoding

M550292-01 Rev G 1-1

Sorensen SFA Series Overview

1.2 TECHNICAL SPECIFICATIONS

The following sections provide environmental, electrical, and physical
characteristics for the SFA Series power supplies.

Note: Specifications are subject to change without notice.
Note: The SFA Series power supplies are intended for indoor use only. Please

refer to Section 2.4 for use/location requirements.

1.2.1 ENVIRONMENTAL CHARACTERISTICS

Parameter Specification

Temperature Coefficient
Ambient Temperature

Operating
Storage

Cooling

Humidity

Altitude

0.03%/°C of maximum output current rating for current set point.

0 to 50°C

-25° to 65°C
Internal fans; vents on sides and rear. (Units may be stacked without

clearance above or below).
95% maximum, non-condensing, 0 to 50°C; 45°C maximum wet-bulb

temperature
Operating full power available up to 5,000 feet (1,524m),

derate 10% of full power for every 1,000 feet higher
non-operating to 40,000 feet (12,192m)

1-2 M550292-01 Rev G

Sorensen SFA Series Overview

1.2.2 ELECTRICAL CHARACTERISTICS

Parameter Specification

Input Power

Voltage (Standard) 208/220 VAC±10% (tested to 187-242 VAC)

Voltage (Options)

Frequency 47 to 63 Hz

Phases

380/400 VAC±10% (tested to 342-440 VAC)
440/480 VAC±10% (tested to 396-528 VAC)

3–phase, 3–wire plus ground. Not phase rotation sensitive.
Neutral not used.

Front Panel Meter Accuracy

Voltage ±0.5% of full-scale + 1 digit
Current ±0.5% of full-scale + 1 digit
Load Regulation (Specified at no load to full load, nominal AC input)
Current 0.1% of maximum output current
Line Regulation (Specified ±10% of nominal AC input, constant load)

Current 0.05% of maximum output current

Current Ripple 1% p-p of full-scale current

The output current will recover to within 1% of the set current

Transient Response

value within 1ms for a 10 to 100% or 100% to 10% step load
change

(10-90% current, full resistive load, nominal AC input):

250A/ms (400A/ms typical) rise, 200A/ms typical fall;

Output Slew Rate

Current Overshoot

Stability

Remote Control/Monitor

Power Factor

M550292-01 Rev G

160V models, 87A/ms/5kW (145A/ms/5kW typical), rise,
60A/ms, typical, fall

100V models, 190A/ms/5kW (238A/ms/5kW typical), rise,
104A/ms, typical, fall

Maximum 8% of full-scale for 0 to 100% change into a resistive
load

±0.05% of set point after 8–hr. warm-up at fixed line, load, and
temperature.

On/Off control via contact closure, 6-120 VDC or 12-240 VAC,
and TTL or CMOS switch, current monitor, OCP limit set,
summary fault status

>0.9 typical for 208/220VAC input
>0.78 typical for 380/400VAC input
>0.7 typical for 440/480VAC input

1-3

Sorensen SFA Series Overview

Parameter Specification

Efficiency 87% typical at full load, nominal line

REMOTE PROGRAMMING

Accuracy

CONSTANT CURRENT ±0.8% of full-scale output
Overcurrent Protection ±1% of full-scale output

Resistive Control Input

CONSTANT CURRENT (0-100%)

Voltage Control Input

Constant Current (0-100%) 0–5 VDC or 0–10 VDC
Overcurrent Protection (OCP)

(0-110%)

Remote Sensing

Overvoltage Protection

ISOLATED ANALOG CONTROL (OPTION)

Input to Output Isolation

0–5 kΩ

0–5.5 VDC

Terminals are provided to sense output voltage at point of load
for accurate voltage measurement.

Fixed at approximately 110% of the rating compliance voltage.
Reset requires cycling the front panel standby power switch
off/on

600 V
Compliant with maximum terminal float voltage. Recommended
operation under SELV normal conditions.
(Standard Non-isolated Analog programming 300V maximum.
Recommended operation under SELV normal conditions).

1.2.3

SFA SERIES VOLTAGE AND CURRENT SPECIFICATIONS

Ratings

Voltage 5 kW 10 kW 15 kW 20 kW 25 kW 30 kW

0-60V 0-83A 0-167A 0-250A 0-333A 0-417A 0-500A
0-100V 0-50A 0-100A 0-150A 0-200A 0-250A 0-300A
0-160V 0-31A 0-63A 0-94A 0-125A 0-156A 0-188A

NOTE: Contact factory for availability on specific models

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Sorensen SFA Series Overview

1.2.4 PHYSICAL CHARACTERISTICS

Dimension 3U Models 6U Models

Width 19.00 in (48.3 cm) 19.00 in (48.3 cm)
Depth 25.12 in (63.8 cm) 25.12 in (63.8 cm)
Height 5.25 in (13.3 cm) 10.5 in (26.7 cm)
Weight 80 lbs (36 kg) maximum 160 lbs (73 kg) maximum

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Sorensen SFA Series Overview

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1-6 M550292-01 Rev G

2.1 INSPECTION

Inspect the shipping carton for possible damage before unpacking the unit.
Carefully unpack the equipment. Save all packing materials until inspection is
complete. Verify that all items listed on the packing slips have been received.
Visually inspect all exterior surfaces for broken knobs, connectors, or meters.
Inspect for dented or damaged exterior surfaces. External damage may be an
indication of internal damage. If any damage is evident, immediately contact the
carrier that delivered the unit and submit a damage report. Failure to do so
could invalidate future claims. Direct repair issues to Customer Service at 1­800-733-5427.

SECTION 2

INSTALLATION

2.2 CONTENTS OF SHIPMENT

Depending on the model, configuration, and options available for your SFA
Series power supply, the ship kit may include additional parts and accessories.
At a minimum, the ship kit that accompanies your SFA Series power supply
includes the following items:

• AMETEK manuals CD-ROM, Part No. M550008-01 containing the
SFA Series DC Power Supplies Operation Manual Part No.
M550292-01 (this manual)

• Sense mating connector (Molex P/N 39-01-4031) with loose contacts
(Molex P/N 39-00-0182)

• J1 mating connector (Cinch P/N DB25P or equivalent) normally
shipped attached to rear panel J1

• Back shell for J1 (DB25) mating connector (Cinch P/N DCH-B-001 or
equivalent)

M550292-01 Rev G 2-1

Installation Sorensen SFA Series

• Screw, lock washer, and nut for AC input and DC output
connections:
5–15 kW: ¼-20UNC-2B x ½", 4 ea AC input only
20–30 kW: 3/8-16UNC-2B x 7/8", 6 ea

• Black screw, 10-32UNC-2B x ½", front panel rack fastener:
5–15 kW: 4 ea
20–30 kW: 8 ea

If any of these parts are missing, please contact Customer Service at
1-800-733-5427.

2.3 INPUT/OUTPUT CONNECTIONS

WARNING!

High voltage present! Risk of electrical shock. Do not remove cover. Refer to
qualified service personnel.

Table 2–1 lists all external connections for the SFA Series models. Table 2–2
and Table 2–3 provide input and output connection descriptions by power
supply type.

For permanently connected equipment, a readily accessible disconnect device
shall be incorporated in the fixed wiring. For pluggable equipment, the socket
outlet shall be installed near the equipment and shall be easily accessible.

Take precautions to ensure that the concentration of ozone is limited to a safe value.
The recommended long-term exposure limit for ozone is 0.1 PPM (0.2 mg/m

3

).

CAUTION!

Do not use the SFA power supplies in series operation.

CAUTION!

For proper connection to the mains, a 100–amp circuit breaker or fuse for 3U
units and a 200–amp circuit breaker or fuse for 6U units is required.

WARNING!

Under no condition should the negative output terminal exceed 300V to earth
ground for non-isolated Analog programming. (600V for supplies with the Isolated
Analog option installed.)

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Sorensen SFA Series Installation

CAUTION!

Floating the negative output terminal floats the power supply’s internal control
circuitry common level to the same potential as the negative output terminal. On a
standard non-isolated supply the common of the analog control connector (J1)
floats at the same potential as the negative output terminal. Damage may occur if
the non-isolated analog control connector of a supply is connected to an external
ground referenced input/output device. Such a connection creates ground loop
currents. To correct ground loop problems the Isolated Analog option is advised in
order to isolate the external ground reference signals from the internal control
circuitry of the supply.

2.4 LOCATION AND MOUNTING

WARNING!

To reduce the risk of fire or electrical shock, install the SFA Series unit in a
temperature and humidity controlled indoor area, free of conductive contaminants.

CAUTION!

The unit should be provided with proper ventilation. The rear and both sides of the
unit should be free of obstructions. To ensure proper airflow, a minimum 4"
clearance from the rear air outlet is required. The unit should not be installed in a
raised ambient temperature greater than 50°C.

2.4.1

CAUTION!

This unit is intended for installation in a protected environment. No user
serviceable parts inside. Service to be performed by qualified personnel only.

The SFA Series models are designed for mounting in a standard 19-inch
equipment rack. If additional instrumentation is mounted in the rack, no
additional clearance is required between the SFA series and other power
supplies or instruments.

1. Support the unit using rack mount slides or appropriate L brackets

(suggested parts are listed below).
Rack Mount Slide Kit:

• 5–15kW units: P/N K550212-01

• 20–30kW units: P/N K550213-01

2. Secure the unit in place using the screws provided.

6U CHASSIS REMOVAL FROM RACK

The slides have a Front Disconnect Feature and lock at full extension.
To return the chassis back into the rack from full extension, depress the flat

steel spring inward (located on the slides) and push the chassis back.
To disconnect and remove the chassis from the rack, depress the flat steel

spring inward (located on the slides) and pull the chassis forward.

M550292-01 Rev G

2-3

Installation Sorensen SFA Series

WARNING!

The 6U SFA Series unit weighs up to 160 lbs (73kg) depending on the model.
A minimum three-person lift is required!

When the chassis is at full extension, the flat springs are located approximately
one (1) inch behind the front EIA RETMA rails. Access the springs with a flat
blade screwdriver or similar device to release from lockout or to remove the
chassis from the rack.

The slides can be mounted to the chassis with this spring oriented on the top or
the bottom of the slide.

Table 2–1 provides details of the SFA Series input and output connectors and
their functions.

Connector Function Connects To

Pos. Threaded Stud
Neg. Threaded Stud
Pos. Bus Bar
Neg. Bus Bar

ANALOG CONTROL
Connector (J1)

Sense Connector Used for remote sense Refer to Section 3.4

Output Power:
3U models (see

6U models (see

Control Interface

Table 2–3)
Table 2–3)

User load(s)

See Table 3–1 for
description

Parallel In-Out Used for parallel operation Refer to Section 3.8

Table 2–1. 5kW to 15kW and 20kW to 30kW Series Input/Output Connectors

Power Supply Type Connection Description

5 kW to 15 kW Bus Bar with holes for 1/4"–20 bolts
20 kW to 30 kW Bus Bar with holes for 3/8"–16 bolts

Table 2–2. Input Connections

Power Supply Type Connection Description

5 kW to 15 kW ≥60V
20 kW to 30 kW ≥60V

3/8" Threaded Studs
Bus Bar with holes for 3/8" bolts

Table 2–3. Output Connections

2-4 M550292-01 Rev G

Sorensen SFA Series Installation

CAUTION!
Prevent damage to the unit: follow torque specifications, use correct size
wire ferrule (if used), and proper size ferrule crimping tool.

TORQUE SPECIFICATIONS

• The unit’s Phoenix Connectors require 18 in-lb to 20 in-lb (2 Nm to

2.3 Nm) torque.

• Wire ferrules are recommended; their size must match the wire

gauge.

• Crimp tool size must be appropriate to the ferrule size.

• Wire insulation should be stripped back no more than 5/8 inch for

the ferrule.

For more information on this AC input connector, please look up Phoenix
Contact part number HDFKV 16 at www.phoenixcontact.com.

M550292-01 Rev G

2-5

Installation Sorensen SFA Series

2.5 WIRE SELECTION

Care must be taken to properly size all conductors for the input and output of
the power supply. This section provides guidance in the selection of wire size.
Note that cables with Class B or C stranding should be used. Fine stranded
cables should not be used unless crimp-on lugs or ferrules are used that are
approved for fine stranded cables.

2.5.1 WIRE SIZE

The tables below will assist in determining the appropriate wire size for both the
input and output connections Table 2–4 below gives minimum recommended
wire size. This table is derived from the National Electrical Code; it is for
reference only. Local laws and conditions may have different requirements.
Note that these recommendations are for copper wire only. For higher ratings,
wires can be paralleled; refer to the National Electrical Code.

Size Temperature Rating of Copper Conductor

60°C 75°C 85°C 90°C

AWG
MCM

Types: RUW,

T, TW, UF

Types: FEPW,

RHW, RH, RUH,

THW, THWN,

XHHW, USE, ZW

Types: V, MI Types: TA, TBS,

SA, AVB, SIS, FEP,
FEPB, RHH, THHN,

XHHW

Current Rating

14 20 20 25 25
12 25 25 30 30
10 30 35 40 40

8 40 50 55 55
6 55 65 70 75
4 70 85 95 95
3 85 100 110 110
2 95 115 125 130
1 110 130 145 150
0 125 150 165 170

00 145 175 190 195

000 165 200 215 225

0000 195 230 250 260

Table 2–4. Minimum Wire Size

When determining the optimum cable specification for your power applications,
the same engineering rules apply whether going into or out of an electrical

2-6 M550292-01 Rev G

Sorensen SFA Series Installation

device. Thus, this guide applies equally to the input cable and output cable for
this Sorensen instrument and application loads.

Power cables must be able to safely carry maximum load current without
overheating or causing insulation destruction. It is important to everyday
performance to minimize IR (voltage drop) loss within the cable. These losses
have a direct effect on the quality of power delivered to and from instruments
and corresponding loads.

When specifying wire gauge, consider the operating temperature. Wire gauge
current capability and insulation performance drops with the increased
temperature developed within a cable bundle and with increased environmental
temperature. Thus, short cables with generously derated gauge and insulation
properties are recommended for power source applications.

Be careful when using published commercial utility wiring codes. These codes
are designed for the internal wiring of homes and buildings and accommodate
the safety factors of wiring loss, heat, breakdown insulation, aging, etc.
However, these codes consider that up to 5% voltage drop is acceptable.

Such a loss directly detracts from the quality performance specifications of this
Sorensen instrument. Also, consider how the wiring codes apply to bundles of
wire within a cable arrangement.

In high performance applications requiring high inrush/ transient currents,
additional consideration is required. The cable wire gauge must consider peak
currents, which may be up to ten times the average values. An underrated wire
gauge adds losses, which alter the inrush characteristics of the application and
thus the expected performance.

Table 2–5 presents wire resistance and resulting cable voltage drop at
maximum rated current.

Column 1 Column 2 Column 3 Column 4

Size

(AWG)

14 20 0.257 5.14
12 25 0.162 4.05
10 30 0.102 3.06

8 40 0.064 2.56
6 55 0.043 2.36
4 70 0.025 1.75

2 95 0.015 1.42
1/0 125 0.010 1.25
3/0 165 0.006 1.04

Amperes

(Maximum)

Ohms/100 Feet

(One Way)

Voltage Drop/100 Feet

(Column 2 x Column 3)

Table 2–5 Wire Resistance and Voltage Drop

M550292-01 Rev G

2-7

Installation Sorensen SFA Series

Refer to Table 2–6 for AC input current requirements and Section 1.2.3 for
output current requirements.

Input V

5 kW 10 kW 15 kW 20 kW 25 kW 30kW

200-240VAC 21 41 62 83 103 124
340-440VAC

480VAC 13 26 39 52 65 78

Refer to Table 2–7 for input/output lug recommendations.

Lug Manufacturer 3U Models Input/Output 6U Models Input/Output

Panduit “PN” Series or equivalent “LCA” Series or equivalent

The recommended tools for installation and extraction of the sense connector
are listed next, in Table 2–8.

Tool

14

Table 2–6 Maximum AC Current Ratings

27 40 54 67 80

Table 2–7 Recommended Lugs

Manufacturer

Input Line Current

Manufacturer P/N

Unit of

Measure

Amps AC

per phase

Crimping Device Molex 11-01-0197
Extracting Device Molex 11-03-0044

Table 2–8. Recommended Sense Connector Tools

2.6 LOAD CONSIDERATIONS

2.6.1 INDUCTIVE LOADS

To prevent damage to the power supply from inductive loads, the SFA has
incorporated a overvoltage shutdown circuit on the output. The overvoltage is
preset for approximately 110% of the total rated output voltage. If the output
voltage exceeds this amount for more than a few milliseconds, the output will
shutdown. In order to reset the unit, the input standby switch, will need to be
cycled on and off.

2.7 OUTLINE DRAWINGS

Figure 2-1 and Figure 2–2, next, show the outlines and overall dimensions of
the 3U and 6U models of the SFA Series product line.

2-8 M550292-01 Rev G

Sorensen SFA Series Installation

Slide Mounting

8-32UNC-2B
4PL Nearside
3PL Far side

Figure 2-1. SFA Series Outline Drawing, 3U Models, 5kW to 15kW

M550292-01 Rev G

2-9

Installation Sorensen SFA Series

Slide Mounting

8-32UNC-2B
6PL Nearside
7PL Far side

Figure 2–2. SFA Series Outline Drawing, 6U Models, 20kW to 30kW

2-10 M550292-01 Rev G

3.1 CONTROLS AND INDICATORS

Refer to Figure 3-1 and the corresponding descriptions below for an explanation
of front panel controls and indicators on the SFA Series power supply.

SECTION 3

OPERATION

Figure 3-1. Front Panel Controls and Indicators (3U model shown)

Voltage Display: 3½ digit green LED display indicates the DC output voltage of the supply.

1

Current Display: 3½ digit green LED display indicates the DC output current of the supply.

2

Display indicates the OCP setting when the SET/RESET OVERCURRENT PROTECTION button
is pushed.

ADJUST Overcurrent Potentiometer: Adjusts the overcurrent trip level.

3

M550292-01 Rev G 3-1

Operation Sorensen SFA Series

CURRENT MODE Indicator: Green LED lights when in the constant–current mode of operation.

4

When in the constant–current mode, the output current will regulate to the set value and the output
voltage will vary with the load. This is the normal operating mode for the SFA.

OVERCURRENT FAULT Indicator: Red LED indicates output current has exceeded preset level,

5

and power supply output is turned off.
MODULE FAULT Indicator: Yellow LED indicates an internal fault such as bias supply, thermal, or

6

converter failure.

SET/RESET OVERCURRENT PROTECTION Pushbutton: Depress button to view OCP

7

level. Push and hold for 4 seconds to reset OCP condition.
CURRENT knob: 10–turn adjustment sets the output current. (Optional shaft locks not

8

shown. Please see Section 3.1.1).
ON/OFF Switch: Two–position switch enables or disables the power supply.

9

WARNING!

The OFF position of the power switch does not remove voltage from the input
terminal blocks. Remove all external power before servicing the unit.

3-2 M550292-01 Rev G

Sorensen SFA Series Operation

Refer to Figure 3-2 and the corresponding descriptions below for an explanation
of rear panel connectors.

10

11 12

151413

17 16

Figure 3-2. Rear Panel Connectors (3U model shown)

DC OUTPUT: Positive (+) and negative (–) outputs. Threaded studs for 5-15kW models; bus bars

10

for 20-30kW models.

ANALOG CONTROL Connector (J1): I/O connector for input programming and analog

11

output monitoring signals as well as status indication and remote shutdown signals.
See Table 3–1 for individual pin descriptions.

18

SENSE Connector (J3): Input connector for load voltage sensing to provide a more

12

accurate voltage measurement for remote voltage readback and front panel voltage
meter display (see Section 3.4).

PARALLEL IN Connector: Allows master/slave configuration of up to five units when

13

connected to another unit’s PARALLEL OUT connector (see Section 3.8).

PARALLEL OUT Connector: Allows master/slave configuration of up to five units when connected

14

to another unit's PARALLEL IN connector (see Section 3.8).

RS232 Connector: Optional RJ-11 connector for remote control.

15

Dipswitch: Eight–position dipswitch to configure an SFA Series unit with an IEEE option.

16

GPIB Connector: Optional connector for remote control.

17

AC Input Bus Bars: Connection for 3-phase AC and Ground.

18

M550292-01 Rev G

3-3

Operation Sorensen SFA Series

3.1.1 SHAFT LOCK (OPTION)

This option replaces the standard control knob with a two-piece shaft lock. This
is installed over the current adjustment potentiometer shaft to prevent rotating
under conditions of shock, vibration, or accidental contact. For adjustment, the
following steps apply:

1. Loosen the shaft by rotating the outer locking nut counter-clockwise
with a 7/16-inch wrench.

2. Adjust the shaft with a flat screwdriver to the desired output level.

3. Tighten the outer locking nut, rotating clockwise, to approximately 5 LB­in (0.56 N-m).

NOTE: Take care not to over-torque the outer nut. Should the cone nut
become loose or jammed with the outer locking nut, re-torque the cone nut with
a 1/2-inch wrench to approximately 15 LB-in (1.69 N-m).

Figure 3-3. Shaft Lock

CAUTION!
Never completely loosen the cone nut, or remove the shaft lock from the
chassis.

3.2 LOCAL OPERATION

The SFA Series power supply is shipped from the factory configured for local
current control and local voltage sensing. The ANALOG CONTROL connector
is supplied with a mating connector with remote ON/OFF jumpered for ON
(terminal 5 shorted to terminal 6).

Prior to turning the unit on, rotate the current potentiometer fully
counterclockwise (minimum output). Then, turn the power ON and adjust the
current to the desired output.

3-4 M550292-01 Rev G

Sorensen SFA Series Operation

This section provides an overview of front panel operation and initial functional
tests of the power supply.

3.2.1 FLOATING AND POLARIZED OUTPUT

The SFA Series supply can be set up for a Positive or Negative supply, as well
as standard operation as a floating output supply.

FLOATING OUTPUT

The output terminals are normally floating from chassis ground. No extra
steps or connections are required for a floating output.

POSITIVE SUPPLY SETUP

Attach the negative output terminal to the supply chassis. The output reference
is now chassis ground. When the output voltage is set or programmed, the
supply will output a positive potential from chassis ground.

NEGATIVE SUPPLY SETUP

Attach the Positive output terminal to the supply chassis. The output reference is
now chassis ground. When the output voltage is set or programmed, the supply
will output a negative potential from chassis ground.

CAUTION!

Floating the negative output terminal floats the power supply’s internal control
circuitry common level to the same potential as the negative output terminal. On a
standard non-isolated supply the common of the analog control connector (J1)
floats at the same potential as the negative output terminal. Damage may occur if
the non-isolated analog control connector of a supply is connected to an external
ground referenced input/output device. Such a connection creates ground loop
currents. To correct ground loop problems the Isolated Analog option is advised in
order to isolate the external ground reference signals from the internal control
circuitry of the supply.

3.2.2 INITIAL SETUP

Before connecting the unit to an AC outlet, ensure that the front panel ON/OFF
power switch is in the off position and that the current control knob is fully
counterclockwise. Check the ANALOG CONTROL (J1) mating connector on the
rear panel to verify that pins 5 and 6 (Remote Output On/Off) are shorted
together to enable the output of the supply (see Section 3.5). This is the default
configuration installed from the factory. Apply power to the AC mains input.

M550292-01 Rev G

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Operation Sorensen SFA Series

3.2.3 CURRENT MODE OPERATION

When the supply is in the Current Mode (the default mode for the SFA Series),
the output current of the supply is controlled by the Current knob on the front
panel or by the remote current input (see Section 3.3). To verify operation in
current mode, follow the steps below:

1. Connect a high current DC ammeter across the rear panel positive and
negative output terminals, observing the correct polarity. Select wire
leads of sufficient current carrying capacity and an ammeter range
compatible with the units maximum rated output current. NOTE: If a
high current ammeter is not available, you may simply short the output
terminals together. This will not harm the supply.

2. Turn on the power supply.

3. Slowly rotate the Current knob clockwise and observe both the front
panel current display and the output of the ammeter. The minimum
range should be from 0A to the maximum rated current output of the
supply. The front panel display and ammeter readings should track
within the accuracies of the meter and the front panel display.

4. Note the reading on the voltage display. This is the compliance voltage
of the load at the present output current. Note the maximum
compliance voltage is set by the specific model of the supply.

5. Check that the green Current Mode indicator is on.

6. Turn the Current knob fully counterclockwise.

7. Turn the power supply off.

8. Disconnect the ammeter or short from the output terminals.

If Current mode operation did not function as indicated above, recheck your
setup and perform the check again. If the function continues to fail, contact the
factory for assistance.

3.2.4 OVERCURRENT PROTECTION

The Overcurrent Protection (OCP) function allows the supply to shutdown the
output when it exceeds a preset current. This may be used to protect sensitive
circuits or loads from damage caused by an excessive current on the output of
the supply. To verify OCP operation, follow the steps below:

1. Connect a short or an appropriate load across the output terminals.

2. Rotate the Current control knob fully counterclockwise (this sets the
current control at 0 Amps)

3. Turn on the power supply.

4. Press and hold the Set/Reset Overcurrent Protection pushbutton on the
front panel and observe the reading on the current display. This is the

3-6 M550292-01 Rev G

Sorensen SFA Series Operation

present setting of the OCP limit. The factory default setting is
approximately 110% of the maximum rated output of the supply.

5. While holding down the Set/Reset button, use a small adjustment

screwdriver to adjust the OCP setting by turning the 4-turn recessed
adjust potentiometer counterclockwise. As you adjust the
potentiometer the reading on the current display should decrease
(increase as you adjust in a clockwise direction).

6. Set the OCP to about 80-90% of the maximum rated output current and

note the OCP current value. Release the Set/Reset pushbutton.

7. Rotate the Current knob clockwise until the current display indicates

you are about 2-3% below the OCP voltage value noted above.

8. Slowly continue to increase the output of the supply until you exceed

the value of the OCP setting. At this point the OCP light should turn on
and the output of the supply will turn off causing the output to go to 0
volts (as indicated on the voltage display).

9. Turn the Current knob fully counterclockwise, then press and hold the

Set/Reset pushbutton until the OCP light turns off.

10. Reset the OCP setting as appropriate for your application per steps 4

and 5 above. If you do not chose to use OCP, then the OCP adjust
may be set fully clockwise to approximately 110% of the rated output
current of the supply.

If OCP mode did not function as indicated above, recheck your setup and
perform the check again. If the function continues to fail, contact the factory for
assistance.

3.2.5 ANALOG CONTROL CONNECTOR (J1)

The ANALOG CONTROL connector on the rear panel allows the unit to be
configured for different operating configurations: local and remote current
programming, current and voltage output monitoring, output enable/disable, etc.
The setup and operating requirements of each configuration are provided in
Sections 3.3 through 3.7.

ISOLATED ANALOG CONTROL (OPTION)

The Isolated Analog Control uses the same Analog Control connector (J1).
This option fully isolates remote control signals and allows control of units not
connected to a common ground. Control ground is isolated from power ground,
which protects against potential damage from systems with high electrical noise
or large ground loop currents.

NOTE: Some standard analog programming signals may not be available with
this option. See Table 1.2.2 for details.

M550292-01 Rev G

3-7

Operation Sorensen SFA Series

CAUTION!

This option is not intended to allow operation of the power supply at excessive
voltages. Refer to Section 2 INSTALLATION for maximum terminal voltages.

Following are Figure 3-4 with the connector's pin-out diagram, and Table 3–1
with ANALOG CONTROL connector designations and functions:

Figure 3-4. ANALOG CONTROL Connector (J1) Pin-out

Schematic

Symbol

Electrical

Chars.

Designator

1

ISO

ON/OFF

Zin ~ 6 kΩ

2 ISO RTN —

3

REM OC

SET

Zin ~

20 kΩ

4 Not Used

Functional Description

Isolated remote on/off. Externally supplied AC/DC voltage source
for on/off control. A positive (+) 12 to 240 VAC or 6 to 120 VDC
voltage will turn on the supply. This input control is optically isolated
from the power supply circuit up to 500 VDC. See Section 3.5.

Isolated circuit return used with isolated on/off control
J1-1 and J1-14.

Remote overcurrent set. A remote signal sets the overcurrent
trip level. 0-5.5 VDC = 0-110%. Apply a 10.5 VDC to 13.3
VDC signal for 4 seconds to reset an OCP condition. See
Section 3.6.

Must sink

5 ON/OFF

~1mA to

enable

6

7 I MON

3-8 M550292-01 Rev G

COM

†

-

Zout ~

100Ω

Remote on/off. Switch/relay contacts or a direct short
between this terminal and circuit common turns on the unit.

Circuit Common. Same potential as the negative output
terminal.

Output current monitor. 0-10 VDC equals 0-100% rated current.
Minimum load resistance 10kΩ.

Sorensen SFA Series Operation

Schematic

Symbol

Electrical

Chars.

Designator

8 Not Used
9 Not Used

10 IP 5V

11

ISET

Zin ~ 10kΩ

*

12 SENSE –

13 SENSE +

Zout ~

100Ω

~ 1000Ω to

neg (–)

output

terminal

~ 1000Ω to

pos (+)

output

terminal

Remote current programming using a 0-5 VDC source.
Do not exceed 13.3 VDC.

0-5 VDC (0-100%) front panel current control monitor output.
Minimum load resistance 10kΩ.

Remote Sense (–) on 60 volts output units.
(For new installations, use J3, recommended only for
backward compatibility in existing systems.)

Remote Sense (+) on <60 volts output units.
(For new installations, use J3, recommended only for
backward compatibility in existing systems.)

Functional Description

Isolated TTL/CMOS on/off control. A high state TTL/CMOS voltage
turns on the power supply, and a low state or open connection turns
the supply off.

14

ISO

TTL/CMOS

Zin ~ 2.2kΩ

15 Not Used

16 IP 10V

Zin ~ 20kΩ

17 FAULT

Zout ~

100Ω

Remote current programming using a 0-10 VDC source.
Do not exceed 25 VDC.

Fault state output. A high state (approximately +10 VDC)
indicates a converter, temperature or bias supply fault, and
the LED on the front panel will illuminate.

Shutdown fault. This terminal goes to high state in the event
of converter, temperature, overvoltage or bias supply fault. A

18 S/D FAULT

Zout ~

100Ω

7 VDC to 13.3 VDC signal can be applied to this pin to
shutdown the output of the unit. An 8 VDC minimum output
signal is provided into a 10 kΩ minimum load, in the event of
an internally generated shutdown.

19 V MON

Zout ~

100Ω

Output voltage monitor. 0-10 VDC equals to 0-100% rated
voltage. Minimum load resistance 10kΩ.

M550292-01 Rev G

3-9

Operation Sorensen SFA Series

Schematic

Symbol

Designator

20 Not Used
21 Not Used

22

23 IP RTN

24

25 IP RTN

IP RES

COM

†

Electrical

Chars.

*

~ 10.8V

compliance

Zin ~ 10kΩ

Zin ~ 10kΩ

-

Functional Description

1 milliamp current source for remote current programming
using resistance. 0-5k ohm resistor referenced to common
will program the output from 0-100%.

Current programming return. Used with J1-10, J1-16 or J1-22
and must be referenced to or within ±3V of the circuit
common.

Circuit common. Same potential as the negative output
terminal.

Current programming return. Used with J1-10, J1-16 or J1-22
for remote current programming and must be referenced to or
within ±3V of the circuit common.

Table 3–1. ANALOG CONTROL Connector (J1), Designations and Functions

†

Control ground is isolated from power ground with the isolated analog control (option).

See Section 3.2.5.1

*

Signals not available with isolated analog control (option).

CAUTION!

If standard analog programming is used, note the programming return (J1-6 &
J1-24) is at the same potential as the negative output terminal of the power
supply. Observance of return connections should be made with respect to input
programming signal equipment. Improper connection may result in ground loops
and as a result internal power supply damage may occur. (Output current then
flows to chassis by means of external connection to the J1 common (J1-6 &
J1-24)).

3-10 M550292-01 Rev G

Sorensen SFA Series Operation

3.3 REMOTE CURRENT PROGRAMMING

Remote current programming is used for applications that require the output
current be programmed (controlled) from a remote source. An external
resistance or external voltage source may be used as a programming device.
When using remote current programming, a shielded, twisted-pair, hookup wire
is recommended to prevent noise interference with programming signals.

1. Remote Current Programming Using Resistance:

The resistance coefficient for remote current programming is 5k
ohms/100% rated output with respect to terminal J1-23 (IP RTN). The
programming current from terminal J1-22 (IP RES) is factory set for 1
milliampere. This yields a coefficient of 1.0% of rated output current for
each 50 ohms. If multiple switches or relays are used to program
different levels, make-before-break contacts are recommended. Note
that if an external resistance is used for remote programming, the
current programming return (IP RTN), terminal J1-23, must be
connected directly to or within ±3 volts (see note) of the power supply
common terminal, J1-24. See Figure 3–5 for connection requirements.

Figure 3–5. Remote Current Programming Using Resistance

2. Remote Current Programming Using a 0-5 VDC or 0-10 VDC Voltage

Source:
A DC voltage source for remote current programming is connected
between J1-10 (IP 5V) or J1-16 (IP 10V) and the return terminal J1-23
(IP RTN). Note that the return terminal J1-23 (IP RTN) must be
referenced directly to or within ±3V (see note) of the power supply
common, J1-24. The voltage coefficient for 5V remote current
programming is 50 millivolts = 1% of rated output, i.e., for a 300 amp
model, each 50 millivolts of programming voltage equals 3 amps of
output current. The voltage coefficient for 10V remote current
programming is 100 millivolts = 1% of rated output, i.e., for a 300 amp

M550292-01 Rev G

3-11

Operation Sorensen SFA Series

model, each 100 millivolts of programming voltage equals 3 amps of
output current. See Figure 3–6 for connection requirements.

1

16 IP 10V

COM 6

IP 5V 10

0-5 VDC
VOLTAGE
SOURCE

+

13

-

23 IP RTN

+

0-10 VDC
VOLTAGE

-

SOURCE

Figure 3–6. Remote Current Programming Using 0-5 VDC or 0-10 VDC Voltage Source

3.4 REMOTE SENSING

Remote voltage sensing is recommended for accurate voltage measurement,
whether you connect sensing leads to the load or directly to the output
terminals. This will provide the most accurate voltage readback and front panel
voltage meter display.

CAUTION!

If the power supply is operated with load power lines disconnected and sensing
line connected, internal power supply damage may occur. (Output current then
flows through sensing terminals.)

To use remote voltage sensing, connect the power supply as described below.
See Figure 3–7 for connection requirements.

Connect sensing leads from the load positive to J3-1 and the load negative to
J3-2. A shielded, twisted-pair, hookup wire is recommended to avoid potential
noise interference.

3-12 M550292-01 Rev G

Sorensen SFA Series Operation

Figure 3–7. Remote Sensing Operation at the Load *

* For accurate measurements through remote voltage readback and front panel
voltage meter display.

M550292-01 Rev G

3-13

Operation Sorensen SFA Series

3.5 REMOTE OUTPUT ON/OFF CONTROL

Remote on/off control may be accomplished by contact closure or by an
isolated external AC/DC or TTL/CMOS voltage source.

1. Remote on/off by contact closure. Output is on when contacts (J1-5
and J1-6) are closed. See Figure 3–8 for connection requirements.

1

ON/OFF 5

6

14

25

Figure 3–8. Remote On/Off Control by Contact Closure

2. Remote on/off control may be accomplished by an external 12 to 240
VAC or 6 to 120 VDC or TTL/CMOS source. Application of AC/DC or
high state TTL/CMOS voltage will turn on the power supply. See
Figure 3–9 and Figure 3–10 for connection requirements.

ISO ON/OFF 1

+

ISO RTN 2

14

-

AC OR DC

SOURCE

25

Figure 3–9. Remote On/Off Using Isolated AC or DC Voltage Source

3-14 M550292-01 Rev G

Sorensen SFA Series Operation

1

ISO RTN 2

14 ISO TTL/CMOS

25

Figure 3–10. Remote On/Off Using Isolated TTL/CMOS Voltage Supply

3.6 REMOTE OVERCURRENT SETPOINT

CAUTION!

Do not program the remote overcurrent set point greater than 10% (5.5V) above
the power supply rated current (except as noted) as internal power supply
damage may occur.

A remote DC voltage source can be connected externally between terminals J1­6 (COM) and J1-3 (REM OC SET) to set the output overcurrent trip level. A 0-

5.5 VDC signal equals 0-110% of rated output voltage. See Figure 3–11 for

connection requirements.

1

REM OV SET 3

0-5.5 VDC
VOLTAGE
SOURCE

+

COM 6

-

13

Figure 3–11. Remote Overcurrent Set Using DC Voltage Source

NOTE: The Remote OCP trip level will ALWAYS take precedence over the

local trip level, even if the local OCP trip level is set to a lower value. To reset
an OCP externally, apply a 10.5–13.3 VDC signal to J1-3 for a minimum of four
(4) seconds.

M550292-01 Rev G

3-15

Operation Sorensen SFA Series

3.7 REMOTE SHUTDOWN (S/D)

A remote +12 VDC voltage can be connected externally between terminals J1­18 (S/D Fault) and J1-24 (COM) to disable, i.e., shut down the output of the
power supply. Disabling or opening the +12 VDC signal will allow the unit to
revert to normal operation.

Figure 3–12. Remote Shutdown Using DC Voltage Source

3.8 MASTER/SLAVE OPERATION

The following modes of operation are used for applications requiring more
current or voltage than is available from a single power supply. To meet the
requirements for greater output voltage or current, up to five supplies may be
connected in parallel.

3.8.1 PARALLEL OPERATION

In the parallel mode of operation, a master/slave configuration is established.
Up to five power supplies may be paralleled using this configuration. To set up
the parallel mode of operation, connect the interface cable (P/N 890-453-03)
from the master unit to the slave unit(s), as shown below in Figure 3–13. Next
connect the positive outputs of supplies together and the negative outputs of the
supplies together. It is recommended that the outputs are connected together
as close to the load as practical.

3-16 M550292-01 Rev G

Sorensen SFA Series Operation

Figure 3–13. Master/Slave Connection

NOTE: The OCP circuit remains active for all units in parallel operation. If the units are set to
different OCP levels, the paralleled system will trip according to the lowest setting. For ease of use,
adjust the OCP levels for the slaves to maximum and adjust the master OCP level to the desired
setting.

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Operation Sorensen SFA Series

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3-18 M550292-01 Rev G

VERIFICATION AND CALIBRATION

4.1 INTRODUCTION

This section provides verification and calibration procedures for the standard
SFA Series power supplies and isolated analog control (option).

SECTION 4

4.1.1 VERIFICATION AND CALIBRATION CYCLE

It is recommended that the power supply be calibrated and/or verified once
each year of operation.

4.1.2 PREPARATION

WARNING!

Hazardous voltages exist on the rear of the supply. Great care must be taken
to avoid both the input terminals, and while the supply is enabled, the output
terminals. Only authorized personnel should perform this procedure.

Due to the importance of accurate readings to performance, only technically
trained personnel should perform calibration procedures.

The calibration and adjustment procedures require two digital multimeters. To
set up for the calibration procedures, first perform the following:

1. Remove prime AC power.

2. Connect the power supply to a precision current shunt (as shown in

Figure 4-1 below) capable of a minimum of 10% above full rated
output. A fan may be required to cool the shunt.

M550292-01 Rev G 4-1

Verification and Calibration Sorensen SFA Series

SHUNT

Figure 4-1. Precision Current Shunt

4.2 STANDARD VERIFICATION AND CALIBRATION

PROCEDURE

All calibration potentiometers can be adjusted through access holes in the top
cover of the SFA Series unit. It is not necessary to remove the top cover to
perform the calibration procedures.

4.2.1 CURRENT MODE

1. Set the SFA Series unit to operate in remote current programming
mode using an external 0-5 Vdc voltage source as shown in Figure 3–6
in Section 3.3 Remote Current Programming.

2. Attach a precision meter across the shunt Kelvin terminals.

3. Attach a precision meter in parallel with the voltage programming
source.

4. Set the voltage source to 0.0V ± 1mV.

5. Apply AC power and verify the current mode indicator is illuminated.

6. Verify the unit is set to 0A ± 0.8% of full-scale output. If necessary,
adjust R55 for zero current through the shunt. (See Figure 4-2.)

7. Set the programming voltage to 5.0V ± 1mV.

8. Verify the unit is set to 100% ± 0.8% of full-scale output current. If
necessary, adjust R69 for 100% of full-scale current on the shunt.

9. Set the programming source for 0.5V ± 1mV.

4-2 M550292-01 Rev G

Sorensen SFA Series Verification and Calibration

10. Verify the unit is set to 10% ± 0.8% of full-scale output current. If

necessary, adjust R55 for 10% of full-scale current on the shunt.

11. Repeat the steps above as required to obtain the required accuracy.

12. Set the programming source to obtain 100% output current on the

shunt. Verify that the front panel meter displays 100% ± 1% of full-scale
output current. If necessary adjust R85 such that the current display
reads 100% current.

CAUTION!

Hazardous voltages may be present on the output after the output is disabled due
to stored capacitive charge. Allow 5 minutes to drain the output capacitive charge
to safe levels before connecting or removing output wiring.

4.2.2

RESISTOR PROGRAMMING CURRENT SOURCES

1. Disable AC power to the unit. Turn the front panel Current knob fully

counterclockwise.

2. Connect the power supply to a precision current shunt (see Figure 4-1,

Section 4.1.2 Preparation).

3. Set the SFA Series unit to operate in remote current programming

mode using resistance by connecting a 5K ohm (1% or better
tolerance) resistor as shown in Figure 3–5 in Section 3.3 Remote
Current Programming.

4. Attach a precision meter across the shunt Kelvin terminals.

5. Apply AC power and enable the unit via the front panel On/Off switch.

6. Verify there is 5V ±1% across the resistor. If necessary, adjust R45 to

measure 5.00V read back on the voltmeter.

7. Disable AC power to the unit.

8. Remove all connections to the remote analog control connector (J1),

except the jumper between pins 5 and 6.

4.3 ISOLATED ANALOG (OPTION) VERIFICATION AND

CALIBRATION PROCEDURE

All calibration potentiometers can be adjusted through access holes in the top
cover of the SFA Series unit. It is not necessary to remove the top cover to
perform the calibration procedures.

M550292-01 Rev G

4-3

Verification and Calibration Sorensen SFA Series

4.3.1 CURRENT MODE

1. Set the SFA Series unit to operate in remote current programming
mode using an external 0-5 Vdc voltage source as shown in Figure 3–6
in Section 3.3 Remote Current Programming.

2. Attach a precision meter across the shunt Kelvin terminals.

3. Attach a precision meter in parallel with the voltage programming
source.

4. Set the voltage source to 0.0V

± 1mV.

5. Apply AC power and verify the current mode indicator is illuminated.

6. Verify that the unit is set to 0A

± 0.8% of full-scale output. If necessary,

adjust R47 for zero current through the shunt (see Figure 4-1 in Section

4.1.2 Preparation).

7. Set the programming voltage to 5.0V

8. Verify that the unit is set to 100%

± 1mV.

± 0.8% of full scale output current. If

necessary, adjust R33 for 100% of full scale current on the shunt.

9. Set the programming source for 0.5V

10. Verify that the unit is set to 10%

± 1mV.

± 0.8% of full scale output current. If

necessary, adjust R47 for 10% of full scale current on the shunt.

11. Repeat the steps above as required to obtain the required accuracy.

12. Set the programming source to obtain 100% output current on the
shunt. Verify that the front panel meter displays 100%

± 1% of full-

scale output current. If necessary adjust R85 such that the current
display reads 100% current.

CAUTION!

Hazardous voltages may be present on the output after the output is disabled.
Allow 5 minutes to drain any charge to safe levels before connecting or removing
output wiring.

4-4 M550292-01 Rev G

Sorensen SFA Series Verification and Calibration

STANDARD CALIBRATION ADJUSTMENT

R71 = IPRES (1mA) Adjust
R87 = Voltage Meter Adjust
R86 = Current Meter Adjust
R69 = 100% Current Adjust
R55 = Zero Current Adjust

ISOLATED ANALOG (OPTION)
CALIBRATION ADJUSTMENT

R86 = Voltage Meter Adjust
R87 = Current Meter Adjust
R33 = 100% Current Adjust
R47 = Zero Current Adjust

FACTORY USE ONLY

R35 R73
R37 R74
R39 R82
R45 R85
R46 R90

Figure 4-2. Potentiometer Locations

M550292-01 Rev G

4-5

Verification and Calibration Sorensen SFA Series

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4-6 M550292-01 Rev G

5.1 INTRODUCTION

This chapter contains preventive maintenance information for the SFA Series
power supplies.

SECTION 5

MAINTENANCE

WARNING!

All maintenance that requires removal of the cover of the unit should only be done
by properly trained and qualified personnel. Hazardous voltages exist inside the
unit. Disconnect the supply from the input power before performing any
maintenance. Service, fuse verification, and connection of wiring to the chassis
must be accomplished at least five minutes after power has been removed via
external means; all circuits and/or terminals to be touched must be safety
grounded to the chassis.

5.2 PREVENTIVE MAINTENANCE

No routine maintenance on the SFA Series is required, aside from periodic
cleaning of the unit when needed:

• Once a unit is removed from service, vacuum all air vents, including the front

panel grill. Clean the exterior with a mild solution of detergent and water.
Apply the solution onto a soft cloth, not directly to the surface of the unit. To
prevent damage to materials, do not use aromatic hydrocarbons or
chlorinated solvents for cleaning.

• Low–pressure compressed air may be used to remove dust from in and

around components on the printed circuit boards.

WARNING!

The OFF position of the power switch does not remove voltage from the input
terminal blocks. Remove all external power before performing any service.

M550292-01 Rev G 5-1

Maintenance Sorensen SFA Series

An annual inspection of the SFA Series unit is recommended. Table 5–1 lists
the visual inspection checks to be performed, and the corrective action to be
taken.

Table 5–1. Recommended Annual Inspection

Item Inspect For Corrective Action

External connector
plugs and jacks

Chassis, fan, and
extruded heatsinks

External electrical
wiring

External solder
connections

Dirt and moisture
buildup

Front panel controls
and meters

Looseness, bent or corroded
contacts, damage or improper
seating in mating connector

Clean contacts with solvent
moistened cloth, soft bristle brush,
small vacuum, or low compressed
air.

Replace connectors damaged,
deeply corroded, or improperly
seated in mating connector.

Dirt and corrosion Clean with cloth moistened with

soapy water.

Broken, burned or pinched

Repair or replace defective wires.

wire; frayed, worn or missing
insulation

Corrosion, loose, cracked, or

Clean and resolder connections.

dirty connections
Short circuits, arcing,

Clean as required.

corrosion, overheating
Dirt and corrosion

Clean with cloth moistened with
soapy water.

Use a Kimwipe tissue and GTC
glass–cleaning compound to clean
the meter faces.

CAUTION!

For safe and continued operation of the SFA Series, always operate the unit in a
temperature and humidity controlled, indoor area, free of conductive
contaminants. Remember to keep the rear and sides of the unit free of
obstructions to ensure proper ventilation.

5-2 M550292-01 Rev G

Sorensen SFA Series Maintenance

5.3 FUSES

There are no user replaceable components in the power supply.

WARNING!

Only properly trained and qualified personnel should remove the cover from the
power supply. Service, fuse verification, and connection of wiring to the chassis
must be accomplished at least five minutes after power has been removed via
external means; all circuits and/or terminals to be touched must be safety
grounded to the chassis.

CAUTION!

To reduce the risk of fire or electrical shock, replace fuses only with the same type
and rating.

Internal fuses are listed in Table 5–2. Note, however, that failure of one of these
fuses indicates a more serious problem has occurred. Please contact the
factory for further assistance.

PCB Part No. Reference Value Manufacturer Part No.

Bias Supply F1, F2, F3 600 Volt, 5 Amp Littelfuse KLK-5

Module Controller F1 600 Volt, 30 Amp Littelfuse KLKD30

Table 5–2. Fuse Values

M550292-01 Rev G

5-3

Maintenance Sorensen SFA Series

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5-4 M550292-01 Rev G

C

Circuit Breaker Requirements, 2-2, 2-5
Controls and Indicators, 3-1

Analog Control (J1), 3-7

Current Mode

Operation, 3-6
Verification and Calibration, 4-2

F

Fuses, 5-3

I

Inductive Loads, 2-8
Input/Output Connections, 2-2

Connector Functions, 2-4

Isolated Analog Control, 3-7

J

INDEX

Mounting Hardware, 2-3

O

Operation

Current Mode, 3-6
Local, 3-4
Master/Slave, 3-16
Parallel, 3-16
Remote Current Programming, 3-11
Remote Output On/Off Control, 3-14
Remote Overvoltage Setpoint, 3-15
Remote Sensing, 3-12

Remote Shutdown, 3-16
Overvoltage Protection, 3-6
Ozone Precaution, 2-2

P

Parallel Operation, 3-16
Potentiometer Locations, 4-5

J1 Connector, 3-7

L

Loads

Inductive, 2-8

Location and Mounting, 2-3

M

Maintenance

Annual Inspection, 5-2
Fuses, 5-3
Preventive, 5-1

Master/Slave Operation, 3-16

M550292-01 Rev G Index 1

Rack slides, 2-3
Remote Current Programming, 3-11
Remote Output On/Off Control, 3-14
Remote Overvoltage Setpoint, 3-15
Remote Sensing, 3-12
Remote Shutdown, 3-16

R

Index Sorensen SFA Series

S
Setup, 3-5
Shaft Lock, 3-4
Specifications, 1-2

Current, 1-4
Electrical Characteristics, 1-3
Environmental Characteristics, 1-2
Noise, 1-4
Physical Characteristics, 1-5
Ripple, 1-4
Voltage, 1-4

V

Ventilation, 2-3
Verification and Calibration, 4-2

Current Mode, 4-2

W

Wire Size, 2-6

Index 2 M550292-01 Rev G