Fluke PPCK PLUS User Manual

PPCK+™

High Pressure Controller/Calibrator

Operation and Maintenance Manual

PPCK+™ Operation and Maintenance Manual

High pressure liquids and gases are potentially hazardous. Energy stored in these liquids and gases can

be released unexpectedly and with extreme force. High pressure systems should be assembled and operated only by personnel who have been instructed in proper safety practices.

transmitted in any form or by any means, electronic or mechanical, for any purpose, without the express written permission of DH Instruments, Inc. 4765 E. Beautiful Lane Phoenix AZ 85044-5318 USA.

DH Instruments makes sincere efforts to ensure accuracy and quality of its’ published materials; however, no warranty, expressed or implied, is provided. DH Instruments disclaims any responsibility or liability for any direct or indirect damages resulting from the use of the information in this manual or products described in it. Mention of any product does not constitute an endorsement by DH Instruments of that product. This manual was originally composed in English and was subsequently translated into other languages. The fidelity of the translation cannot be guaranteed. In case of conflict between the English version and other language versions, the English version predominates.

DH Instruments, DH, DHI, AutoZ, PPC, PPC2+, PPCK+, Thermal Pressure Control (TPC) and AutoZ are trademarks, registered and otherwise of DH Instruments, Inc.

Products described in this manual are manufactured under international patents and one or more of the following U.S. patents: 5,142,483, 5,257,640, 5,331,838, 5,445,035. Other U.S. and international patents pending.

Document No. 550118a-01 20011213

Printed in the USA

PPCK+™ Operation and Maintenance Manual

AABBLLEE

TABLE OF CONTENTS................................................................................ i

TABLES................................................................................................... iv

FIGURES .................................................................................................. v

ABOUT THIS MANUAL .............................................................................. vi

1. INTRODUCTION .................................................................................... 1

1.1 PRODUCT OVERVIEW .............................................................................................................................1

1.2 SPECIFICATIONS .....................................................................................................................................2

2. INSTALLATION ..................................................................................... 7

2.1 UNPACKING AND INSPECTION..............................................................................................................7

2.2 SITE REQUIREMENTS..............................................................................................................................8

2.3 INITIAL SETUP..........................................................................................................................................8

2.4 POWER-UP AND VERIFICATION...........................................................................................................14

2.5 SHORT TERM STORAGE.......................................................................................................................15

1.2.1 GENERAL SPECIFICATIONS...........................................................................................................................2

1.2.2 PRESSURE MEASUREMENT SPECIFICATIONS............................................................................................2

1.2.2.1 REFERENCE PRESSURE TRANSDUCER (RPT) SPECIFICATIONS.............................................3

1.2.2.2 ON-BOARD BAROMETER................................................................................................................4

1.2.3 PRESSURE CONTROL SPECIFICATIONS......................................................................................................4

2.1.1 REMOVING FROM PACKAGING......................................................................................................................7

2.1.2 INSPECTING CONTENTS.................................................................................................................................7

2.3.1 PREPARING FOR OPERATION........................................................................................................................8

2.3.2 FRONT AND REAR PANELS............................................................................................................................9

2.3.2.1 FRONT PANEL..................................................................................................................................9

2.3.2.2 REAR PANEL ASSEMBLY..............................................................................................................10

2.3.3 POWER CONNECTION...................................................................................................................................10

2.3.4 CONNECTING THE HIGH PRESSURE SUPPLY (SUPPLY PORT) ..............................................................11

2.3.5 CONNECTING TO THE DEVICE UNDER TEST (TEST PORT)......................................................................11

2.3.6 CONNECTING THE DRIVE PRESSURE SUPPLY (DRIVE IN PORT) ...........................................................12

2.3.7 DRIVE OUT PORT...........................................................................................................................................12

2.3.8 VENT PORT.....................................................................................................................................................13

2.3.9 THE DRAIN PORT...........................................................................................................................................13

2.3.10 THE ATM PORT (BAROMETER) ....................................................................................................................13

2.4.1 SWITCH POWER ON.......................................................................................................................................14

2.4.2 CHECK PROPER PRESSURE MEASUREMENT OPERATION.....................................................................14

2.4.2.1 CHECKING ABSOLUTE MODE PRESSURE MEASUREMENT ....................................................14

2.4.2.2 CHECKING GAUGE MODE PRESSURE MEASUREMENT...........................................................14

2.4.3 LEAK CHECK..................................................................................................................................................15

2.4.4 CHECK PROPER PRESSURE CONTROL OPERATION...............................................................................15

NTTEE

NTTSS

PPCK+™ Operation and Maintenance Manual

3. OPERATION ....................................................................................... 17

3.1 GENERAL/MANUAL OPERATION .........................................................................................................17

3.2 DIRECT FUNCTION KEYS......................................................................................................................28

3.3 SETUP MENU KEY .................................................................................................................................46

3.4 SPECIAL MENU KEY..............................................................................................................................47

3.1.1 MAIN RUN SCREEN........................................................................................................................................17

3.1.2 GENERAL OPERATING PRINCIPLES ...........................................................................................................18

3.1.2.1 KEYPAD LAYOUT AND PROTOCOL..............................................................................................18

3.1.2.2 MANUAL PRESSURE CONTROL KEYS........................................................................................19

3.1.2.3 PRESSURE CONTROL OPERATING PRINCIPLES ......................................................................20

3.1.2.4 AUTOMATED PRESSURE CONTROL MODES.............................................................................22

3.1.2.5 PRESSURE READY /NOT READY.................................................................................................25

3.1.2.6 MULTIPLE PRESSURE RANGES...................................................................................................27

3.1.2.7 DIRECT FUNCTION KEYS SUMMARY ..........................................................................................28

3.2.1 [RANGE]...........................................................................................................................................................28

3.2.1.1 RANGE SPECIFIC FUNCTIONS AND SETTINGS .........................................................................30

3.2.2 [UNIT]...............................................................................................................................................................31

3.2.3 [CONTROL]......................................................................................................................................................32

3.2.3.1 SYSTEM DEFAULT CONTROL PARAMETERS.............................................................................34

3.2.3.2 EXECUTING AUTOMATED PRESSURE CONTROL COMMANDS...............................................34

3.2.4 [UL] (UPPER LIMIT) ........................................................................................................................................34

3.2.4.1 OVERPRESSURE FUNCTION........................................................................................................35

3.2.5 [SEQ] SEQUENCE...........................................................................................................................................35

3.2.6 [CUSTOM CONTROL].....................................................................................................................................36

3.2.6.1 TURNING-OFF CUSTOM CONTROL PARAMETERS....................................................................37

3.2.7 [HEAD].............................................................................................................................................................38

3.2.8 [LEAK CHECK]................................................................................................................................................39

3.2.9 [RES] (RESOLUTION).....................................................................................................................................41

3.2.10 [SET P] (SETTING PRESSURE AUTOMATICALLY)......................................................................................42

3.2.10.1 AUTOMATED PRESSURE COMMANDS FOR ZERO PRESSURE...............................................44

3.2.11 [←] AND [→] (JOG PRESSURE SET POINT) ................................................................................................45

3.3.1 SEQUENCE......................................................................................................................................................46

3.3.2 DRIVERS..........................................................................................................................................................46

3.4.1 AUTOZ..............................................................................................................................................................47

3.4.1.1 VIEW AUTOZ...................................................................................................................................50

3.4.1.2 EDIT AUTOZ....................................................................................................................................51

3.4.1.3 RUN AUTOZ....................................................................................................................................51

3.4.2 HEAD................................................................................................................................................................54

3.4.3 PresU ...............................................................................................................................................................55

3.4.4 INTERNAL........................................................................................................................................................56

3.4.4.1 CONFIG...........................................................................................................................................57

3.4.4.2 CAL..................................................................................................................................................58

3.4.4.3 REMOTE..........................................................................................................................................59

3.4.4.4 TIME.................................................................................................................................................60

3.4.4.5 RESET.............................................................................................................................................61

3.4.4.6 LEVEL..............................................................................................................................................63

3.4.4.7 ATM..................................................................................................................................................66

3.4.4.8 SCRSAV ..........................................................................................................................................67

3.4.4.9 LOG..................................................................................................................................................67

4. REMOTE OPERATION ......................................................................... 69

4.1 OVERVIEW..............................................................................................................................................69

4.2 INTERFACING.........................................................................................................................................69

4.2.1 RS232 INTERFACE.........................................................................................................................................69

4.2.1.1 COM1...............................................................................................................................................69

4.2.1.2 IEEE-488..........................................................................................................................................70

4.2.1.3 COM2...............................................................................................................................................70

PPCK+™ Operation and Maintenance Manual

4.3 PROGRAMMING FORMATS...................................................................................................................71

4.3.1 CLASSIC PROGRAM MESSAGE FORMAT...................................................................................................71

4.3.2 ENHANCED PROGRAM MESSAGE FORMAT...............................................................................................71

4.3.2.1 ENHANCED PROGRAM MESSAGE USING THE COMMAND TYPE............................................72

4.3.2.2 ENHANCED PROGRAM MESSAGE USING THE QUERY TYPE..................................................72

4.4 COMMANDS............................................................................................................................................73

4.4.1 PROGRAM MESSAGES..................................................................................................................................73

4.4.2 ERROR MESSAGES .......................................................................................................................................75

4.4.3 PROGRAM MESSAGE DESCRIPTION OVERVIEW......................................................................................76

4.4.4 PROGRAM MESSAGE DESCRIPTIONS........................................................................................................77

4.5 STATUS REPORTING SYSTEM...........................................................................................................107

4.5.1 ERROR QUEUE.............................................................................................................................................107

4.5.2 STATUS BYTE REGISTER............................................................................................................................108

4.5.3 STANDARD EVENT REGISTER...................................................................................................................110

4.5.4 READY STATUS REGISTER.........................................................................................................................111

4.6 IEEE STD. 488.2 COMMON AND STATUS PROGRAM MESSAGES..................................................111

4.6.1 PROGRAM MESSAGE DESCRIPTIONS......................................................................................................112

5. MAINTENANCE, ADJUSTMENTS AND CALIBRATION ...........................115

5.1 OVERVIEW............................................................................................................................................115

5.2 CALIBRATION OF REFERENCE PRESSURE TRANSDUCERS.........................................................116

5.2.1 PRINCIPLE.....................................................................................................................................................116

5.2.1.1 PA AND PM COEFFICIENTS........................................................................................................117

5.2.1.2 SETTING ZNATERR......................................................................................................................117

5.2.1.3 ORDER OF OPERATIONS............................................................................................................118

5.2.1.4 AS RECEIVED/AS LEFT DATA.....................................................................................................118

5.2.2 EQUIPMENT REQUIRED ..............................................................................................................................119

5.2.3 SET-UP AND PREPARATION.......................................................................................................................120

5.2.4 RPT CALIBRATION USING CALTOOL FOR RPTs SOFTWARE................................................................120

5.2.5 EDITING AND VIEWING RPT CALIBRATION INFORMATION....................................................................120

5.2.6 SETTING ZNATERR......................................................................................................................................122

5.2.7 RPT CALIBRATION/ADJUSTMENT WITHOUT CALTOOL FOR RPTs SOFTWARE.................................122

5.3 ADJUSTMENT OF ON-BOARD BAROMETER.....................................................................................124

5.4 DRAIN PURGE ......................................................................................................................................124

5.5 RELOADING EMBEDDED SOFTWARE INTO FLASH MEMORY........................................................125

5.6 SUBASSEMBLY DESCRIPTION AND LOCATION ..............................................................................126

5.6.1 LOW PRESSURE PNEUMATIC MODULE....................................................................................................126

5.6.2 HIGH PRESSURE PNEUMATIC MODULE...................................................................................................126

5.6.3 DRIVER BOARD............................................................................................................................................127

5.6.4 POWER SUPPLIES .......................................................................................................................................128

5.6.5 ON-BOARD BAROMETER............................................................................................................................128

5.6.6 MICRO CARD.................................................................................................................................................128

5.6.7 THERMAL PRESSURE CONTROL UNIT (TPCU)........................................................................................128

5.6.8 REFERENCE PRESSURE TRANSDUCER (RPT)........................................................................................128

6. TROUBLESHOOTING .........................................................................129

7. APPENDIX .........................................................................................135

7.1 DRIVERS ...............................................................................................................................................135

7.2 UNIT CONVERSION..............................................................................................................................137

7.2.1 PRESSURE....................................................................................................................................................137

7.3 GLOSSARY...........................................................................................................................................138

7.4 WARRANTY STATEMENT....................................................................................................................140

PPCK+™ Operation and Maintenance Manual

AABBLLEES

Table 1. Model Designations and Ranges

Table 2. Default Pressure Control Parameters .......................................................................................5

Table 3. PPCK+ Packing List .................................................................................................................. 7

Table 4. Static and Dynamic Pressure Control Modes Summary.........................................................22

Table 5. PPCK+ Range Identification Summary...................................................................................27

Table 6. Summary of PPCK+ Direct Function Key Operation...............................................................29

Table 7. Default Pressure Control Parameters .....................................................................................34

Table 8. UNIT Function - Available Units..............................................................................................55

Table 9. Security Levels........................................................................................................................65

Table 10. Pin Designations and Connections .........................................................................................70

Table 11. List of PPCK+ COM2 DB-9M Pin Designations......................................................................70

Table 12. Program Message List.............................................................................................................73

Table 13. Error #’s and Descriptions.......................................................................................................75

Table 14. 8 Bit Status Byte Register......................................................................................................108

Table 15. 8 Bit Standard Event Register...............................................................................................110

Table 16. 8 Bit Ready Status Register..................................................................................................111

Table 17. Program Message List...........................................................................................................111

Table 18. Troubleshooting Guide..........................................................................................................129

Table 19. Driver Output .........................................................................................................................135

Table 20. External Drivers.....................................................................................................................136

Table 21. Conversion Coefficients ........................................................................................................137

Table 22. DHI Authorized Service Providers.........................................................................................141

..............................................................................................3

PPCK+™ Operation and Maintenance Manual

Figure 1. Front Panel................................................................................................................................9

Figure 2. Rear Panel Assembly..............................................................................................................10

Figure 3. Keypad Layout.........................................................................................................................18

Figure 4. Manual Pressure Control Keys................................................................................................19

Figure 5. Pneumatic Schematic..............................................................................................................21

Figure 6. Static Pressure Control Operation...........................................................................................23

Figure 7. Dynamic Pressure Control Operation .....................................................................................24

Figure 8. Ready/Not Ready in Static Control Mode..............................................................................26

Figure 9. Ready/Not Ready in Dynamic Control Mode.........................................................................26

Figure 10. Status Register Schematic....................................................................................................108

Figure 11. Internal View..........................................................................................................................126

Figure 12. Pneumatic Module, High and Low.........................................................................................127

Figure 13. Driver Cable Schematic.........................................................................................................136

IIG

URREESS

PPCK+™ Operation and Maintenance Manual

This manual is intended to provide the user with the basic information necessary to operate a PPCK+ pressure controller/calibrator. It also includes a great deal of additional information provided to allow you to optimize its use and take full advantage of its many features and functions.

Before using the manual, take a moment to familiarize yourself with the table of contents structure: Sections 1, 2 and 3 should be read by all first time PPCK+ users. Section 3 is most important for those using the local front panel interface but should be read over by all users to familiarize themselves with general PPCK+ operating principles. Section 4 is for remote operation from an external computer. Section 5 provides maintenance and calibration information. Section 6 is a quick troubleshooting guide. Use it to troubleshoot unexpected PPCK+ behavior based on the symptom of that behavior.

For those of you who “don’t read manuals”, go directly to Section 2.3 to set up your PPCK+ and then

Section 2.4 for power-up and verification. This will get you running quickly with a minimal risk of causing damage to yourself or your new PPCK+. THEN… when you have questions or start to wonder about all the great features you might be missing, get into the manual!

Certain words and expressions have specific meaning as they pertain to PPCK+. The Glossary Section (Section 7.3) is useful as a quick reference for exact definition of specific words and expressions as they are used in the manual.

BBO

UTT

HIISS

Manual Conventions

AAN

UAALL

(CAUTION) is used in manual to identify user warnings and cautions.

(NOTE) is used in the manual to identify operating and applications advice and additional

explanations.

[ ] indicates direct function keys (e.g., [RANGE]). < > indicates PPCK+ screen displays (e.g., <1yes>).

PPCK+™ Operation and Maintenance Manual

1. INTRODUCTION

1.1 PRODUCT OVERVIEW

PPCK+ is a stand-alone, microprocessor driven, pressure controller/calibrator intended to precisely measure and control precise gas pressure as needed for the calibration and testing of pressure measuring instruments. PPCK+ offers very high performance combined with maximum versatility and ease of use. PPCK+ is designed to cover very high gas pressures, especially ranges above 7 MPa (1 000 psi). PPCK+ measures and controls pressure in ranges from 0 to 1 000 psi (7 MPa) up to 0 to 10 000 psi (70 MPa), in both gauge and absolute measurement modes. For pressure ranges of 7 MPa (1 000 psi) and below, see DHI’s PPCK+ pressure controller/calibrator.

PPCK+ measures pressure using a high precision reference pressure transducer (RPT) and an on-board barometer. Pressure control is achieved by pneumatically actuated high pressure valves and a patented thermal pressure control (TPC) system for very fine adjustment.

PPCK+ can be controlled locally by the operator through the front panel display, keypad and special function keys or remotely over an RS232 or IEEE-488 interface using ASCII character command strings.

PPCK+™ Operation and Maintenance Manual

1.2 SPECIFICATIONS

1.2.1 GENERAL SPECIFICATIONS

Power Requirements: 85 to 264 VAC, 47 to 440 Hz, 60 VA max. consumption

Operating Temperature Range: 15 to 35 °C

Storage Temperature Range: -20 to 70 °C

Vibration: Meets MIL-T-28800D

Weight: 15.4 kg (34 lb)

Dimensions: 18 cm H x 32 cm W x 40 cm D (7.1 in. H x 12.6 in. W x 15.8 in. D)

Microprocessor: Motorola 68302, 16 MHz

Communication Ports: RS232 (COM1), RS232 (COM2), IEEE-488.2

Pressure Ranges: Each PPCK+ has three ranges (H1, H2, H3). Ranges are from 0 to

1 000 psi (7 MPa) to 0 to 10 000 psi (70 MPa). (See Table 1.)

Operating Medium:

Pressure Supplies:

Pressure Connections: High Pressure Supply: DH200 F

Pressure Limits: Maximum Working Pressure: Range H3 +10 %

Any clean, dry, non-corrosive gas SUPPLY port: Range H3 + 5 %, supply pressure must remain

DRIVE IN port: 700 - 850 kPa (100 - 120 psi), supply must remain

Test and Drain: DH200 F Vent: 1/8 in. NPT F Drive In: 1/8 in. NPT F Drive Out: 1/8 in. NPT F ATM (on-board barometer): 10-32 UNF Note: DH200 F is a gland and collar type fitting for coned and left hand threaded 1/4 in. (6 mm) OD tube, equivalent to AE SF250C, HIP LF4, etc.

Maximum Pressure without Damage: Range H3 +20 % Maximum Working Supply Pressure: Range H3 + 10 % Maximum Supply Pressure without Damage: Range H3 + 20 %

constant ± 1 % to meet control specifications constant ± 5 % to meet control specifications

1.2.2 PRESSURE MEASUREMENT SPECIFICATIONS

Each PPCK+ has three ranges using one Reference Pressure Transducers (RPT) and a barometer. All three ranges operate in both gauge and absolute mode.

All RPTs are of the absolute pressure type using an evacuated, permanently sealed reference. Gauge pressures are defined by offsetting atmospheric pressure with dynamic compensation for atmospheric changes using the on-board barometer (see Section 3.4.1, Gauge Mode, Dynamic Compensation for Atmospheric Pressure

PPCK+™ Operation and Maintenance Manual

Table 1. Model Designations and Ranges

RPT

DESIGNATION RANGE1 (LO) RANGE2 (MID) RANGE3 (HI) RANGE1 (LO) RANGE2 (MID) RANGE3 (HI)

A10000

A6000

A3000

US UNITS VERSION (psi) SI UNITS VERSION (MPa)

3 000 6 000 10 000 20 40 70 2 000 4 000 6 000 13 25 40 1 000 2 000 3 000 6 12 20

Note: All ranges are both absolute and gauge and support all measurement units available. The “US” or “SI” distinction only affects the nominal range values and settings.

1.2.2.1 REFERENCE PRESSURE TRANSDUCER (RPT) SPECIFICATIONS

All values are ± FS of the active range unless otherwise indicated.

Warm Up Time: 30 minutes for best performance

Resolution: To 1 ppm, user settable by individual range

Temperature Effect: Fully compensated from 0 to 50 °C with active independent

temperature measurement

0.005 % maximum temperature effect in normal ambient 15 to 35° C operating range

Acceleration Effect:

Measurement Precision

Predicted Stability

Measurement Uncertainty3: 90 day 1 year

± 0.008 %/g maximum, worst axis Allows operation at ± 20° from reference plane without significant effect

± 0.01 %

: 90 day 1 year

Gauge Mode (w/Autozero): 0.003 % 0.009 % Absolute Mode (w/Autozero): 0.003 % 0.009 % Absolute Mode (w/out Autozero): 0.006 % 0.015 %

Gauge Mode (w/Autozero): 0.012 % 0.015 % Absolute Mode (w/Autozero): 0.012 % 0.015 % Absolute Mode (w/out Autozero): 0.015 % 0.020 %

1 Measurement Precision: Combined linearity, hysteresis, repeatability of measurements made

by the reference pressure transducer.

2 Predicted Stability: Maximum change in zero and span over specified time period for typical

RPT used under typical conditions. As stability can only be predicted and varies from RPT to RPT, stability for a specific RPT should be established from experience.

3 Measurement Uncertainty: Maximum deviation of the reference pressure transducer indication

from the true value of measured pressure including precision, stability, temperature effect and calibration standard uncertainty of ± 0.005 % of reading.

The influence of the dynamic compensation for atmospheric pressure in gauge mode

measurement is less than ± 2.5 Pa (0.00035 psi).

PPCK+™ Operation and Maintenance Manual

1.2.2.2 ON-BOARD BAROMETER

The on-board barometer is NOT used as a source of absolute accuracy. It is ONLY used to measure changes in atmospheric pressure between zeroing opportunities to provide dynamic compensation of the RPTs atmospheric pressure offset when making gauge pressure measurements.

1.2.3 PRESSURE CONTROL SPECIFICATIONS

All values are ± FS of the active range unless otherwise indicated.

Modes and Ready Indication: Static: Sets pressure within hold limit and maintains rate of

Pressure is Ready when within hold limit and rate of Dynamic: Sets pressure within hold limit and continuously adjusts Pressure is Ready when within hold limit

Control Parameters: Hold limit, stability limit (optimum values set by default, can be

customized independently for each measurement range)

Control Precision1: ± 0.003 %, ± 0.01 % default dynamic control hold limit

Normal Test Volume: PPCK+ A3000: 0 to 500 cc (100 cc optimal)

PPCK+ A6000: 0 to 200 cc (50 cc optimal) PPCK+ A10000: 0 to 200 cc (50 cc optimal) Note: Pressure control system will operate in larger volumes but

pressure setting times are increased.

change lower than stability limit change is less than stability limit as close as possible to target

Gas is a compressible fluid. The larger the pressurized

the volume, the larger the stored energy. The size of high pressure volumes should be minimized for safety

Control Speed: Slew Rate (0 to Controller FS)

in Optimal Volume with No Control: 60 to 120 seconds Pressure Setting (Typical Time To Ready Indication for a 10 % Increment in Dynamic Mode): 90 seconds (reduced by increasing hold limit)

Minimum Pressure: Gauge Mode: 0 (vented)

Absolute Mode: Atmospheric pressure (vented)

Minimum Controlled Pressure: No limit (greater than atmosphere)

Delivered Pressure Uncertainty

: 90 day 1 year

Gauge Mode: 0.016 % 0.018 % Absolute Mode (w/Autozero): 0.016 % 0.018 % Absolute Mode (w/out Autozero): 0.018 % 0.022 %

1 Control Precision: Minimum useable hold limit in dynamic control mode. 2 Delivered Pressure Uncertainty: Maximum deviation from the true value of pressure applied to the device under

test in dynamic control mode with default control limits and assuming measurement uncertainty as in Section 1.2.2.1. In static control mode, the control error can be eliminated making delivered pressure uncertainty equal to measurement uncertainty.

PPCK+™ Operation and Maintenance Manual

Table 2. Default Pressure Control Parameters

DYNAMIC CONTROL MODE STATIC CONTROL MODE

HOLD LIMIT STABILITY LIMIT HOLD LIMIT STABILITY LIMIT

± 0.01 % FS of active pressure range

± 0.005 % FS/sec of active pressure range

± 1% FS of active pressure range

± 0.005 % FS/sec of

active pressure range (used only when control is not active)

PPCK+™ Operation and Maintenance Manual

OOTTEES

PPCK+™ Operation and Maintenance Manual

2. INSTALLATION

2.1 UNPACKING AND INSPECTION

2.1.1 REMOVING FROM PACKAGING

PPCK+ is delivered in a corrugated container with high density polyethylene inserts to hold it in place; or in the optional molded medium density polyethylene shipping case with a custom foam insert.

Remove the PPCK+ and its accessories from the shipping container and remove each element from its protective plastic bag.

2.1.2 INSPECTING CONTENTS

Check that all items are present and have NO visible damage. A standard PPCK+ includes all items indicated in Table 3.

Table 3. PPCK+ Packing List

DESCRIPTION PART NO.

PPCK+ Pressure Controller/Calibrator

PPCK+ A3000 PPCK+ A6000

PPCK+ A10000 Calibration Certificate 550100 Test Report 550120 Accessories: 401655 or 401655-CE

User’s Manual 550118

Power Cord (7.5 ft.) 100770 or 100770-CE

(6) Rubber Feet Caps 400203

General Accessories Disk (Important: Includes

system support software and documentation)

Nip, SS, DH200, 2.75 in. 100204

Gland, SS, DH200, 7/16-20 100272

Plug, SS, DH200, 4T 100279

Adpt, SS, DH200F x 2NPTF 100299

(2) Clr, SS, DH200 101200

FAM0006-01

102987

PPCK+™ Operation and Maintenance Manual

2.2 SITE REQUIREMENTS

The PPCK+ can be installed on any flat, stable surface at a convenient height. The front feet can be extended so that the unit can be inclined slightly for easier viewing. The PPCK+ can also be mounted in a standard 19 in. rack mount using the optional rack mount kit.

Minimizing the length of tubing connecting the PPCK+ to the device or system to be tested

enhances control performance and reduce pressure setting times. Ready access to the PPCK+ rear panel should be considered to facilitate making and breaking

pressure connections when necessary. Support facilities required include:

• An electrical power source of 85 to 264 VAC, 47 to 440 Hz.

• A continuous regulated high pressure supply of clean, dry, non-corrosive gas at maximum

PPCK+ range (H3) + 5 % to be connected to the SUPPLY port. Supply pressures of less than range H3 + 5 % may cause out of tolerance pressure control. The SUPPLY source must remain stable ± 1 % while PPCK+ is controlling. If a gas booster is used to supply high pressure, an accumulator is required to dampen the pressure changes caused by the booster cycling. Consider using the DHI GB-K gas booster package.

• A continuous regulated drive air pressure supply of clean, dry non-corrosive gas at 700 to 850 kPa (100 to 120 psig). The drive air supply must remain stable ± 5 % during PPCK+ operation. This DRIVE pressure supplies the precision low pressure control system that actuates PPCK+’s high pressure valves. The flow and consumption requirements are extremely low. Use of instrument grade nitrogen or air from a compressed air bottle is recommended. If shop or factory air is used, a filter/dryer must be installed. The DHI GB-K gas booster package includes a DRIVE air regulator and connection.

2.3 INITIAL SETUP

2.3.1 PREPARING FOR OPERATION

To prepare PPCK+ for check out and operation:

n Remove the plastic caps from the PPCK+ rear panel pressure connections. o Remove the protective plastic sheet from the front panel display. p Install the rubber feet caps onto the bottom case feet, if desired. q Familiarize yourself briefly with the front and rear panel (see Section 2.3.2).

PPCK+™ Operation and Maintenance Manual

2.3.2 FRONT AND REAR PANELS

2.3.2.1 FRONT PANEL

The front panel assembly provides a 2 x 20 vacuum fluorescent display of PPCK+ operating status and a membrane keypad for local user control.

1. Display 3. Manual Pressure Control Keys

2. Multi-Function Keypad 4. Remote Indicator

Figure 1. Front Panel

PPCK+™ Operation and Maintenance Manual

2.3.2.2 REAR PANEL ASSEMBLY

The rear panel assembly provides pressure connections, communications interfaces, the power ON/OFF module and product labeling. Pressure fittings are internally secured to prevent loosening when making and breaking connections.

1. Label, Product 9. Pass Through, ATM REF (10-32 UNF)

2. COM2 Connector 10. DRAIN Port (DH200 F)

3. IEEE-488 Connector 11. TEST Port (DH200 F) 4 COM1 Connector 12. VENT Port (1/8 in. NPT F)

5. Fuse 13. DRIVE OUT Port (1/8 in. NPT F)

6. Power Switch 14. DRIVE IN Port (1/8 in. NPT F)

7. Power Plug (IEC320-C13) 15. SUPPLY Port (DH200 F)

8. Drivers Option Connector

Figure 2. Rear Panel Assembly

2.3.3 POWER CONNECTION

n Check that the PPCK+ power switch is OFF. o Connect the supplied power cable to the rear panel power module. p Connect the other end of the power cable to an electrical supply of 85 to 264 VAC,

47 to 440 Hz.

PPCK+™ Operation and Maintenance Manual

2.3.4 CONNECTING THE HIGH PRESSURE SUPPLY (SUPPLY PORT)

The SUPPLY port is for connection of the high pressure gas that PPCK+ controls. Using a pressure connecting hose or rigid tube of appropriate pressure rating, connect the

pressure supply to the SUPPLY port on the rear panel of PPCK+. The SUPPLY connection is DH200 F.

DH200 F is a gland and collar type fitting for coned and left hand threaded 1/4 in. (6 mm) OD

tube, equivalent to AE SF250C, HIP LF4, etc. DO NOT USE INCORRECT FITTINGS; DAMAGE TO THE FITTING AND DANGER TO THE OPERATOR COULD RESULT.

The supply pressure should be equal to the maximum PPCK+ range + 5 %. The supply pressure must be stable ± 1 % for PPCK+ pressure control to operate within specifications (see Section 1.2.3).

Never connect a pressure supply greater than 20 % over the maximum range (H3) of the

PPCK+ model you are using. Always use the correct fittings.

Take care NOT to connect the high pressure supply to a port other than the SUPPLY port.

CONNECTING THE HIGH PRESSURE SUPPLY TO ANY PORT OTHER THAN THE SUPPLY PORT MAY DAMAGE THE PPCK+ AND MAY CAUSE OPERATOR INJURY.

2.3.5 CONNECTING TO THE DEVICE UNDER TEST (TEST PORT)

The TEST port is for connection of the PPCK+ to the system into which it will measure and control high gas pressures.

Using a pressure connecting hose or hard tube of appropriate pressure rating, connect the device or system to be tested to the TEST port. The PPCK+ TEST connection is DH200 F.

DH200 F is a gland and collar type fitting for coned and left hand threaded 1/4 in. (6 mm)

OD tube, equivalent to AE SF250C, HIP LF4, etc. DO NOT USE INCORRECT FITTINGS; DAMAGE TO THE FITTING AND DANGER TO THE OPERATOR COULD RESULT.

Gas is a compressible fluid. The larger the pressurized volume, the larger the stored energy.

The size of high pressure volumes should be minimized for safety.

NEVER apply pressure to the TEST port greater than the PPCK+ maximum range (H3)

working pressure. Internal damage to the PPCK+ may result.

Operating the PPCK+ connected to a system with liquid contaminants without taking proper

precautions to purge the system and test line may cause contamination of the PPCK+ that will affect measurement and control performance and require non-warranty service.

PPCK+™ Operation and Maintenance Manual

Minimizing the length and complexity of the test connection tubing enhances control

performance and reduces pressure setting time. For optimum operation, the total volume of the device or system under test including connecting tubing should be less than 500 cc

(30 in

) up to 200 MPa (3 000 psi) and less than 200 cc (12 in3) over 200 MPa (3 000 psi).

PPCK+ pressure control will not operate properly if there are excessive leaks in the

test system. As a general rule, the maximum acceptable leak rate for optimal PPCK+ automated pressure control operation and to assure in tolerance measurements with default pressure control parameters is ± 0.01 % of active range FS/second. If working with larger leaks is unavoidable, consider using STATIC CONTROL mode (see Section 3.1.2.4).

2.3.6 CONNECTING THE DRIVE PRESSURE SUPPLY (DRIVE IN PORT)

PPCK+’s high pressure valves are actuated by a drive pressure. This drive pressure must be connected and properly set for PPCK+ to operate properly.

Using a pressure connecting hose of appropriate pressure rating, connect the drive pressure supply to the DRIVE IN connection on the rear panel of PPCK+. The DRIVE IN connection is 1/8 in. NPT F.

The drive pressure must be between 700 - 850 kPa (100 - 120 psi). The supply pressure must be stable ± 5 % for PPCK+ pressure control to operate within specifications (see Section 1.2.3).

Never connect a pressure supply to the DRIVE IN port that is greater than 1 MPa (150 psi).

Damage to PPCK+ could result.

2.3.7 DRIVE OUT PORT

The DRIVE OUT port is the exhaust point for drive air used by PPCK+’s high pressure valve drive system (see Figure 5). The DRIVE OUT port should be open to atmosphere and unobstructed to allow drive air to escape. The drive air consumption is very low so there is no significant flow through the DRIVE OUT port.

Though a pressure hose can be connected to the DRIVE OUT port to direct the exhausted gas flow, the flow is very low and a completely unobstructed connection to atmosphere must be maintained.

The PPCK+ DRIVE OUT port is 1/8 in. NPT female.

NEVER plug, obstruct or connect a supply pressure to the DRIVE OUT port.

PPCK+™ Operation and Maintenance Manual

2.3.8 VENT PORT

The PPCK+ VENT port is the test exhaust port as well as the vent to atmosphere point used to set zero gauge pressure. Though a pressure hose can be connected to the VENT port to direct the vented gas flow, a completely unobstructed connection to atmosphere must be maintained for PPCK+ reference pressure measurements to operate normally.

The PPCK+ VENT port is 1/8 in. NPT female.

NEVER plug, obstruct or connect a supply pressure to the PPCK+ VENT port.

2.3.9 THE DRAIN PORT

The DRAIN port connects to the low point in the PPCK+ thermal pressure control volume (see Figures 2, 12). The volume serves as a sump to trap small quantities of liquids that may return to PPCK+ from the system connected to the TEST port.

The PPCK+ is delivered with a plug installed in the DRAIN port and the port is left plugged during normal operation. The DRAIN port should occasionally be purged by slowly opening the fitting with approximately 700 kPa (100 psi) trapped in the PPCK+ (see Section 5.4).

The PPCK+ DRAIN connection is DH200 F.

DH200 F is a gland and collar type fitting for coned and left hand threaded 1/4 in. (6 mm)

OD tube, equivalent to AE SF250C, HIP LF4, etc. DO NOT USE INCORRECT FITTINGS; DAMAGE TO THE FITTING AND DANGER TO THE OPERATOR COULD RESULT.

2.3.10 THE ATM PORT (BAROMETER)

The ATM pass through is connected to the on-board barometer. The ATM pass through assures that the on-board barometer is exposed to atmospheric pressure rather than to the pressure inside the PPCK+ case which may be slightly different from atmospheric pressure.

For calibration or verification of the on-board barometer through the ATM port, a pressure reference may be connected. The ATM REF port connection is 10-32 UNF F.

Do not plug or obstruct the ATM REF pass through as this may adversely affect GAUGE

mode operation.

NEVER connect a pressure greater than 110 kPa ABSOLUTE (16.5 psia) to the ATM REF port

or damage to the on-board barometer may result.

PPCK+™ Operation and Maintenance Manual

2.4 POWER-UP AND VERIFICATION

2.4.1 SWITCH POWER ON

Actuate the power switch on the PPCK+ rear panel. Observe the front panel display as PPCK+ initializes, error checks and goes to the main run screen (see Section 3.1.1).

PPCK+ operating condition at power-up is all valves closed. Powering down PPCK+ also causes all valves to close.

If the PPCK+ fails to reach the main run screen, service is required. Record the sequence of operation and displays observed and contact a DHI Authorized Service Provider (see Table 22).

The pressure range that was active on power down is active on power up.

2.4.2 CHECK PROPER PRESSURE MEASUREMENT OPERATION

2.4.2.1 CHECKING ABSOLUTE MODE PRESSURE MEASUREMENT

Check that the PPCK+ operates properly in absolute mode. If the PPCK+ is not vented, press the [VENT] manual pressure control key to vent

the PPCK+ (VENT LED ON) (see Section 3.1.2.2). Open the TEST port as well to be sure the RPT is exposed to atmospheric pressure.

Press the [UNIT] function key and select <absolute> measurement mode (see Section 3.2.2). Change the pressure unit if desired (see Section 3.2.2).

Observe the current value of atmospheric pressure displayed on the PPCK+ main run screen (see Section 3.1.1). Check that the value agrees with the local value of atmospheric pressure within measurement tolerances. Repeat this process for all three PPCK+ ranges. Check that the values of atmospheric pressure measured by the different ranges agree with each other within PPCK+ measurement tolerances (see Section 1.2.2). If the values do not agree within tolerances, PPCK+ may need calibration or repair.

2.4.2.2 CHECKING GAUGE MODE PRESSURE MEASUREMENT

If the PPCK+ is not vented, press the [VENT] manual pressure control key to vent the PPCK+ (VENT LED ON) (see Section 3.1.2.2). Open the TEST port as well to be sure the RPT is exposed to atmospheric pressure.

Press the [UNIT] function key and select <gauge> mode (see 3.2.2). Change the pressure unit if desired (see Section 3.2.2).

PPCK+™ Operation and Maintenance Manual

Observe that, within 60 seconds, the [VENT] LED flashes and zero is indicated. It is normal for PPCK+ to indicate a value other than zero for up to 60 seconds when first entering gauge mode.

Using the [RANGE] function key to change ranges, observe that zero is indicated for each range within 60 seconds. When gauge mode is first entered or ranges are changed, it is normal for PPCK+ to indicate a value other than zero when vented. After up to 60 seconds, the VENT LED should flash and zero should be indicated. If this does not occur, check that the AUTOZERO function is ON (see Section 3.4.1) and that the TEST port is truly exposed to atmospheric pressure. If the display will not zero, PPCK+ may need repair.

2.4.3 LEAK CHECK

If desired, perform a leak check of the test system (see Section 3.2.8).

2.4.4 CHECK PROPER PRESSURE CONTROL OPERATION

Select a pressure range using the [RANGE] key (see Section 3.2.1). Press the [CONTROL] function key and select <dynamic> (see Section 3.2.3). Press [ENTER]. Specify a target pressure within the active range and press [ENTER] again

(see Section 3.2.3). PPCK+ should set the target pressure and indicate Ready (see Section 3.1.2.5) continuously

within 45 to 150 seconds. If it does not, see Section 6 to troubleshoot pressure control. Remember that the correct pressure supplies must be connected to the SUPPLY pressure DRIVE IN pressure ports for pressure control to operate properly (see Sections

2.3.6, 3.1.2.3).

Before setting a pressure with PPCK+, assure that the test system connected to the PPCK+

TEST port is rated for the pressure that will be generated.

2.5 SHORT TERM STORAGE

The following is recommended for short term storage of PPCK+:

n Vent the PPCK+. o Turn power OFF using the rear panel power switch. p Shut OFF or disconnect the pressure supply. q Shut OFF or disconnect the drive air supply.

PPCK+™ Operation and Maintenance Manual

OOTTEES

PPCK+™ Operation and Maintenance Manual

3. OPERATION

3.1 GENERAL/MANUAL OPERATION

PPCK+ is designed to balance simple, intuitive operation and the availability of a wide variety of functions with a high level of operator discretion. The local operator interface is through a 2 x 20 display, 4 x 4 keypad and four manual pressure control keys on the front panel.

3.1.1 MAIN RUN SCREEN

The PPCK+ main run screen is its home display that is reached on power-up and from which other functions and menus are accessed. It is the very top level of all menu structures.

The main run screen is where the operator works with PPCK+ to set and read pressures. It provides complete information on the system's current configuration and operating status.

1. Ready/Not Ready indication (see Section 3.1.2.5):

*PRESSURE1 UNITM hzSR TPRESSURE2 CC NN/NN

4. Pressure measurement mode: <g> gauge, <a> absolute (see Section 3.2.2).

5. Head correction indication: Indicates whether a head correction is applied. <h> if applied, < > (blank) if not (see Section 3.2.7).

6. Autozero indication: Indicates whether the autozero function is ON or OFF. <z> if ON; < > (blank) if OFF (see Section 3.4.1).

7. Range indicator: Indicates <H> for high RPT and <1> for low range, <2> for mid range, <3> for high range (see Section 3.2.1).

8. Sequence counter: Not used in PPCK+.

9. Control mode indicator: Pressure control mode (<S> for static, <D> for dynamic, <M> for manual) with a <C> appended if custom control settings are in use. Shows <VLV> when the inlet or exhaust valve is in its opening routine (see Sections 3.1.2.3, 3.1.2.4). The control mode indicator characters flash when the system is controlling pressure (see Sections 3.2.3, 3.2.6).

10. PRESSURE2: Numerical sign and value of either target pressure <T>, rate of change of pressure <R> or deviation from target <D>. Target value and deviation are in the current pressure unit of measure. Rate of change of pressure is in current unit per second (see Section 3.2.3).

<*> when Ready, <↑> or <↓> indicating direction of measured pressure evolution if Not Ready.

2. PRESSURE1: Numerical value and sign of pressure measured by active RPT and range.

3. UNIT: Current pressure unit of measure (see Section 3.2.2).

PPCK+™ Operation and Maintenance Manual

11. Indicates whether the number following is target pressure <T>, rate of change of pressure <R> or current deviation from target value <D>) (see Section 3.2.3).

Target pressure <T> is indicated when:

• Dynamic control is active and pressure is Not Ready.

• Static control is active and pressure is outside of the hold limit.

Deviation <D> is indicated when:

• Dynamic control is active and pressure is Ready.

Rate of change <R> is indicated when:

• No control is active (e.g., control is suspended or system is vented).

• Static control is active, and pressure is inside the hold limit.

PPCK+ has a screen saver function which causes the display to dim if no key is pressed for

10 minutes. Pressing a key restores full power to the display. The screen saver time can be changed or screen saving can be completely suppressed (see Section 3.4.4.8).

3.1.2 GENERAL OPERATING PRINCIPLES

3.1.2.1 KEYPAD LAYOUT AND PROTOCOL

The PPCK+ has a 4 x 4 keypad for local operator access to direct functions, function menus and for data entry.

1. The Function/Data keys allow very commonly used functions to be accessed directly by a single keystroke when pressed from the main run screen. The name of the function is on the bottom half of the key (see Sections 3.1.2.7, 3.2). These keys enter numerical values when editing.

2. The Editing and Execution keys are for causing execution, suspending execution, backing up in menus and editing entries.

3. The Menu/Data keys provide access to function menus when pressed from the main run screen. The menu name is on the bottom half of the key. The SETUP menu is for more frequently used functions (see Section 3.3). The SPECIAL menu is for functions that are not generally used as a part of day to day operation (see Section

3.4). These keys enter numerical values when editing.

Figure 3. Keypad Layout

PPCK+™ Operation and Maintenance Manual

Pressing [ENTER] within a menu or function generally causes execution or forward movement in the menu tree. Pressing [ENTER] from the main run screen allows an automated pressure control command to be given.

Pressing [ESCAPE] moves back in the menu tree and/or causes execution to cease or suspend. Pressing [ESCAPE] repeatedly eventually brings you back to the main run screen and from there will allow a momentary viewing of the PPCK+ introduction screen.

Pressing [+/-] changes a numerical sign when editing. It also toggles through multiple screens when available.

Pressing [←] or [→] allows reverse or forward cursor movement when editing data entry. These keys also allow the target pressure value to be jogged up and down while controlling or when editing the target value.

Some screens go beyond the two lines provided by the display. This is indicated by a

flashing arrow in the second line of the display. Press the [←] and [→] keys to move the cursor to access the lines that are not visible or directly enter the number of the hidden menu choice if you know it.

3.1.2.2 MANUAL PRESSURE CONTROL KEYS

The manual pressure control keys provide direct operator control of pressure increase, decrease and vent. They can be useful in adjusting pressure when automated pressure control to a target value is not needed.

The manual pressure control keys interrupt and override automated pressure control. Pressing the [VENT] key causes PPCK+ to execute its vent routine in which

pressure is controlled to near atmospheric pressure and then the exhaust valve is fully opened. A RED LED just above the [VENT] key indicates the PPCK+ is in vent mode. The vent valve will remain open until the [VENT] key is pressed again, another manual pressure control key is pressed, or an automated pressure control command is given.

Pressing [↑] or [↓] causes pressure to increase or decrease at the slow slew rate. These are momentary keys that are active only as long as they are pressed. Releasing the key stops the pressure increase or decrease.

Pressing and holding the [FAST] key while pressing the [↑] or [↓] causes the pressure increase or decrease speed to change from slow to fast.

Figure 4. Manual Pressure Control Keys

PPCK+™ Operation and Maintenance Manual

3.1.2.3 PRESSURE CONTROL OPERATING PRINCIPLES

Numerical references in this section refer to Figure 5. PPCK+ is designed to precisely measures and control gas pressures into a volume

connected to its TEST port (14). Pressure is measured by a Reference Pressure Transducer (RPT)(17).

Pressure is controlled in two stages. The first stage of pressure control is valve control. Valve control is used for all

aspects of pressure control except the final stage of dynamic pressure control in which pressure is maintained at the target value (see Section 3.1.2.4). Valve control is accomplished by high pressure inlet and exhaust valves (3, 11). The HP inlet valve (3) controls the admission of pressure from the SUPPLY port (1). The HP exhaust valve (11) controls the exhaust of pressure out of the VENT port (13). The HP inlet and HP exhaust valves are dome-loaded needle valves. The valve is normally closed by a Belleville spring. The valve is opened and its needle position is controlled by the application of drive pressure onto the dome in opposing force to the Belleville spring. The drive pressure is supplied from the DRIVE IN port (6) and controlled by the drive air solenoid valves (2, 4, 10, 12).

When a command is given to set a pressure, the high pressure inlet (3) or exhaust (11) valve must be opened to admit or exhaust pressure. The opening procedure takes 5 to 10 seconds during which PPCK+ may appear to be idle. To notify the operator that the valve opening procedure is in process, the main run screen pressure control characters FLASH <VLV> during the valve opening routine (see Section 3.1.1).

The second stage of pressure control is thermal pressure control (TPC). TPC is used in the final stage of dynamic pressure control when very fine control is needed to maintain pressure at the target value (see Section 3.1.2.4). TPC, uses a pressurized volume in which there is a heating element and around which there is a forced air cooling system (16). Heating and cooling the gas in the volume causes it to expand or contract, increasing or decreasing pressure. This patented, pressure control system allows extremely fine pressure control without hysteresis or wear of mechanical parts.

The TPC system response is dependent on the volume connected to the TEST port. Whenever TPC response indicates that the test volume has changed, PPCK+ runs an automated routine to determine the new test volume. This routine is initiated automatically when needed. The execution of the volume determination routine may occur occasionally while TPC is active in dynamic control mode. This normal behavior appears as a delay in pressure control during which the pressure may vary by up to 700 kPa (100 psi). The volume determination configuration can also be launched by the user (see Section 3.4.4.1).

PPCK+™ Operation and Maintenance Manual

1. SUPPLY Port (DH200 F) 11. High Pressure Exhaust Valve

2. HP Inlet Valve Dome Exhaust Valve 12. HP Exhaust Valve Dome Exhaust Valve

3. High Pressure Inlet Valve 13. VENT Port (1/8 in. NPT F) 4 HP Inlet Valve Dome Supply Valves 14. TEST Port (DH200 F)

5. Drive Air Lines 15. DRAIN Port (DH200 F)

6. DRIVE IN Port (1/8 in. NPT F) 16. Thermal Pressure Control Unit (TPCU)

7. Drive Air Filter 17. Reference Pressure Transducer (RPT)

8. Drive Air Regulator (factory adj.) 18. High Pressure Filter(s)

9. DRIVE OUT Port (1/8 in. NPT F) 19. High Pressure Lines

10. HP Exhaust Valve Dome Exhaust Valves

Figure 5. Pneumatic Schematic

PPCK+™ Operation and Maintenance Manual

3.1.2.4 AUTOMATED PRESSURE CONTROL MODES

PPCK+ automated pressure control provides automated adjustment and control of pressure to a user designated target value. This feature allows pressure values to be set precisely by simple numerical entry. Pressing [SET P] from the main run screen allows a pressure control target value to be entered and executed. Pressing [ESCAPE] or a manual pressure control key causes active pressure control to be interrupted (see Section 3.1.2.2).

PPCK+ supports two pressure control modes to meet different pressure setting and controlling requirements. The two control modes are designated static and dynamic. Pressure control parameters for each control mode are automatically set to optimal default values for each PPCK+ range when the control mode is selected in the active range (see Sections 3.2.1, 3.2.3). If desired, control parameters can be customized by the user using the CUSTOM CONTROL function (see Section 3.2.6).

Control parameters:

• Target Value: The pressure setpoint specified by the operator.

• Hold Limit: A symmetrical positive and negative limit around the target value

within which the controlled pressure is to be maintained.

• Stability Limit: A rate of change of pressure limit in units of pressure/second used as a criterion for the Ready/Not Ready condition in static control or when automated control is not active.

See STATIC CONTROL and DYNAMIC CONTROL in this section for a detailed explanation of each control mode and its advantages, the default control parameters and the Custom Control options. See Table 4 for a summary of the two control modes.

Table 4. Static and Dynamic Pressure Control Modes Summary

CONTROL

MODE

Static

Dynamic

• Control error can be completely eliminated.

• Minimizes pressure setting time (Ready to Ready).

• Provides maximum tolerance for leaks in test volume.

• Set pressure is equal to target pressure.

• When testing multiple DUTs, final pressure is the same for all DUTs at each set point.

ADVANTAGES

DISADVANTAGES

• May require averaging of DUT readings for best results.

• When testing multiple DUTs, final pressure is not exactly the same for each DUT at a set point.

• Set pressure is not equal to target pressure.

• Control error is added to measurement uncertainty.

• Increases pressure setting time (Ready to Ready).

• Limited tolerance of leaks in test volume.

BEST USED

• When data acquisition from the DUT is automated allowing averaging of the DUT readings.

• When minimizing uncertainty is a priority.

• When reducing pressure setting time is a priority.

• When DUT readings must be recorded manually.

• When it is imperative that the final pressure be equal to the set pressure requested.

+ 120 hidden pages