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.
This instrument is not to be operated in any other manner than that specified by the manufacturer.
Information in this document is subject to change without notice. No part of this document may be reproduced or transmitted in any
form or by any means, electronic or mechanical, for any purpose, without the express written permission of DH Instruments, a
Fluke Company 4765 East 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 or brand does not constitute an
endorsement by DH Instruments of that product or brand. 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.
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.
AutoRange, AutoZ, DH Instruments, DH, DHI, COMPASS, PPC, PPC3, QDUT, Q-RPT, RPM, RPM4, SDS and SPLT are
trademarks, registered and otherwise, of DH Instruments, a Fluke Company.
Document No. 550128b-02
050815
Printed in the USA.
2.3.1 PREPARING FOR OPERATION...................................................................................................................6
2.3.2 FRONT AND REAR PANELS........................................................................................................................7
2.3.2.1 FRONT PANEL..........................................................................................................................................7
2.3.3 POWER CONNECTION.................................................................................................................................8
2.3.4 REMOTE [ENTER/SET P] CONNECTION (FOOTSWITCH OR OTHER SWITCH) .....................................8
2.3.5 CONNECTING TO A PRESSURE SUPPLY (SUPPLY PORT).....................................................................8
2.3.6 CONNECTING A VACUUM PUMP (EXHAUST PORT) ................................................................................8
2.3.7 CONNECTING EXTERNAL Q-RPTS IN RPM4 REFERENCE PRESSURE MONITORS.............................9
2.3.8 CONNECTING TO THE DEVICE UNDER TEST (TEST(+) AND TEST(-) PORTS)....................................10
2.3.8.1 INSTALLING A SELF PURGING LIQUID TRAP (SPLT) .........................................................................11
2.3.8.2 INSTALLING A DUAL VOLUME UNIT (DVU), G15K AND BG15K Q-RPTS...........................................12
2.3.9 THE VENT PORT.........................................................................................................................................12
2.3.11 TURN OFF ABSOLUTE AND NEGATIVE GAUGE MODE (AXXX RPT)....................................................12
2.4 POWER-UP AND VERIFICATION.........................................................................................................13
2.4.1 SWITCH POWER ON ..................................................................................................................................13
3.1 USER INTERFACE................................................................................................................................15
3.1.1 MAIN RUN SCREEN....................................................................................................................................15
3.1.2 FUNCTION / DATA KEYPAD LAYOUT AND PROTOCOL.........................................................................17
3.1.3 DIRECT PRESSURE CONTROL KEYS......................................................................................................18
3.5.1.2 RUN AUTOZ.............................................................................................................................................62
5.2.3 SET-UP AND PREPARATION...................................................................................................................124
5.2.4 RECOMMENDED CALIBRATION POINT SEQUENCE............................................................................124
5.2.4.1 STANDARD CLASS Q-RPTS................................................................................................................125
5.2.4.2 PREMIUM CLASS Q-RPTS...................................................................................................................126
5.2.5 TURNING OFF ABSOLUTE AND NEGATIVE GAUGE MEASUREMENT MODES FOR AXXX
( AB S O L U T E ) Q - R P T S .........................................................................................................................
5.2.6 Q-RPT CALIBRATION USING CALTOOL FOR RPTS SOFTWARE........................................................128
5.2.7 EDITING AND VIEWING Q-RPT CALIBRATION INFORMATION............................................................128
5.2.8 Q-RPT CALIBRATION/ADJUSTMENT WITHOUT CALTOOL FOR RPTS SOFTWARE.........................130
5.3 ADJUSTMENT OF ON-BOARD BAROMETER...................................................................................131
5.4 ADJUSTMENT OF UTILITY SENSOR ................................................................................................131
5.5 PNEUMATIC CONTROL MODULE CONFIGURATION (<CONFIG>) ................................................132
5.7 RELOADING EMBEDDED SOFTWARE INTO FLASH MEMORY......................................................134
5.8 SUBASSEMBLY DESCRIPTION AND LOCATION ............................................................................135
5.8.1 POWER SUPPLY MODULE......................................................................................................................135
5.8.2 MINI MICRO BOARD.................................................................................................................................135
5.8.3.1 HI Q-RPT OR UTILITY SENSOR...........................................................................................................136
5.8.3.2 LO Q-RPT...............................................................................................................................................136
Figure 1. Front Panel ...................................................................................................................................7
This manual is intended to provide the user with the basic information necessary to operate a PPC3
pressure controller/calibrator. It also includes a great deal of additional information provided to allow you
to optimize PPC3 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 PPC3 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 PPC3 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 PPC3 behavior based on the symptom of that behavior. Certain words and
expressions have specific meaning as they pertain to PPC3. The Glossary, Section 6, is useful as a
quick reference for exact definition of specific words and expressions as they are used in the manual.
For those of you who “don’t read manuals”, go directly to Section 2.3 to set up your PPC3 and then go
to Section 2.4 for power-up and verification. This will get you up and running quickly with a minimal
risk of causing damage to yourself or your new PPC3. THEN… when you have questions or start to
wonder about all the great features you might be missing, get into the manual!
T
T
HHIISS
M
AANNUUAAL
M
L
Manual Conventions
(CAUTION) is used in throughout the manual to identify user warnings and cautions.
(NOTE) is used throughout the manual to identify operating and applications advice and
additional explanations.
[ ] indicates direct function keys (e.g., [RANGE]).
PPC3 is a stand-alone, pressure controller intended to precisely set and control gas pressure into a
closed volume as is commonly needed for the calibration and testing of pressure measuring instruments.
It has been designed to provide very high performance combined with maximum versatility and ease of use.
PPC3 can be equipped with a low cost utility sensor for pressure monitoring or one or two Quartz Reference
Pressure Transducers (Q-RPTs) to allow it to set and measure pressure with very low measurement
uncertainty. Up to four external Q-RPTs in one or two external Reference Pressure Monitors (RPM4s),
can also be integrated into a PPC3 system. In some cases, a barometer is also included.
Pressure control is achieved by a patented pneumatic module based on digitally controlled solenoid
valves and differential pressure regulators.
PPC3 is controlled locally by the operator using a front panel display, keypad and function keys or
remotely by a computer using ASCII character command strings over an RS232 or IEEE-488.2 interface.
PPC3 models are available to measure and control pressure in ranges from as low as - 3 to 3 kPa (0.4 psi)
to as high as 0 to 10 MPa (0 to 1 500 psi) in absolute, gauge and compound gauge measurement modes.
1.2 SPECIFICATIONS
1.2.1 GENERAL SPECIFICATIONS
Power Requirements
Operating Temperature Range
Storage Temperature Range
Vibration
Weight
Dimensions
Ventilation
Microprocessors
Communication Ports
Fuses
Pressure Ranges
Operating Medium
Pressure Connections
Pressure Limits
85 to 264 VAC, 50/60 Hz, 30 VA max consumption
15 to 35 °C
- 20 to 70 °C
Meets MIL-T-28800D
12.7 kg (28.2 lb) approx
18 cm H x 32 cm W x 40 cm D (7.1 in. x 12.6 in. x 15.8 in.)
To prevent product overheating, provide proper ventilation. Allow 10 cm
(4 in.) clearance from rear panel cooling fan.
Motorola 68302, 16 MHz
RS232 (COM1), RS232 (COM2), IEEE-488.2
1 A, 250 VAC fuse, 5 x 20 mm, time lag type fuse
Internal power supply fuse not replaceable by operator: 2A, 250 V (UV 440-2
power supply), 3.15A, 250 V (NFS40-7612 power supply)
Six controller models from 200 kPa (30 psi) max to 10 MPa (1 500 psi) max.
Low uncertainty measurement provided by selection of quartz reference
pressure transducer(s) (Q-RPTs)
Any clean, dry, non-corrosive gas
SUPPLY: 1/8 in. NPT F
TEST(+): 1/8 in. NPT F
TEST(-): 1/8 in. NPT F
ATM (Vent): 10-32 UNF
EXHAUST: 1/4 in. NPT F
Maximum Working:Pressure: Controlle r or Hi Q-RPT maximum
Maximum Test Pressure:w/out Damage: 110 % controller or Hi Q-RPT
Recommended Supply: Pressure: Maximum control pressure + 10 %
Maximum Supply Pressure: w/out Damage:
Quartz reference pressure transducers (Q-RPTs) can be installed in PPC3 to obtain
low uncertainty pressure measurement. One or two Q-RPTs can be included in the
PPC3 and/or additional Q-RPTs can be used externally mounted in DHI RPM4
Reference Pressure Monitors (see Section 3.2.4).
The type (Axxx, Gxxx, BGxxx, BAxxx) and range of the Q-RPT module(s)
determines the PPC3 measurement specifications.
All Q-RPTs whose maximum pressure is over 200 kPa (30 psi) are of the absolute
pressure type (Axxx) using an evacuated, permanently sealed reference. Axxx Q-RPTs
can measure absolute, gauge and negative gauge pressure. Gauge pressure with
an Axxx (absolute) Q-RPT is obtained by offsetting atmospheric pressure and
applying dynamic compensation for atmospheric changes using the on-board
barometer (see Section 3.2.3). Gxxx (gauge) Q-RPTs can measure positive gauge
pressure only. BGxxx (bi-directional gauge) Q-RPTs can measure gauge and
negative gauge pr essure. See Se cti on 3.3. 3, P RIN CIP LE, for additional information on
absolute, gauge and negative gauge measurement modes.
PPC3s configured with two Q-RPT modules have only one TEST(+) and TEST(-) port.
PPC3 internal valves and logic handle switching between the two Q-RPTs as needed.
Q-RPTs are available with two different performance levels, STANDARD class
and PREMIUM class. See the product label on the PPC3 rear panel, the label
on the Q-RPT module on the rear panel and/or the product calibration
reports to determine the class of the Q-RPTs installed in PPC3.
Table 1. Reference Pressure Transducer (Q-RPT) Designations and Ranges
Resolution
Compensated Temperature Range
Acceleration Affect
Allows operation at ± 20° from
significant effect
Predicted One Year Stability
1
Precision
2
Measurement Uncertainty3
Delivered Pressure Uncertainty4
1. Predicted Q-RPT measurement stability limit (k=2) over one year assuming regular use of AutoZero function. AutoZero
occurs automatically in gauge mode whenever vented, by comparison with barometric reference in absolute mode.
Absolute mode predicted one year stability without AutoZ is ± (0.005 % Q-RPT span + 0.005 % of reading).
2. Combined linearity, hysteresis, repeatability. Add + 1 Pa (0.00015 psi) in gauge mode with an Axxx (absolute) Q-RPT for
the resolution and short term stability of the on-board barometer.
3. Maximum deviation of the Q-RPT indication from the true value of applied pressure including precision, predicted one year
stability limit, temperature effect and calibration uncertainty, combined and expanded (k=2) following the ISO “Guide to the
Expression of Uncertainty in Measurement.”
4. Maximum deviation of the PPC3 controlled pressure from the true value including measurement uncertainty and dynamic
control hold limit.
5. % of reading value times measured pressure from 100 to 30 % of Q-RPT span. Under 30 % of Q-RPT span, % of reading
value times 30 % of Q-RPT span. For example, if the Q-RPT is a Standard A160K, the Measurement Uncertainty in
pressure is 0.010% times the measured pressure to 48 kPa (160 kPa span x 30%) and 0.0048 kPa (160 kPa span x 30%
x 0.01%) under 48 kPa.
6. % of reading value times measured pressure from 100 to 30 % of AutoRanged span. Under 30% of AutoRanged span, %
of reading value times 30% of AutoRanged span. If AutoRanged span is less then 30% of maximum Q-RPT span, % of
reading values times measured pressure, or % of reading times 9% of Q-RPT span, whichever is greater. For example, if
the Q-RPT is a Premium A160K and AutoRanged span is 160 kPa, the Measurement Uncertainty in pressure is measured
pressure x 0.008% to 48 kPa (160 kPa AutoRanged span x 30%) and 0.0038 kPa (160 kPa span x 30% x 0.008%) under
48 kPa. If the AutoRanged span is 100 kPa (greater than 30% of 160 kPa maximum Q-RPT span), the measurement
uncertainty in pressure is measured pressure x 0.008% to 30 kPa (100 kPa AutoRanged span x 30%) and 0.0024 kPa
(100 kPa span x 30% x 0.008%) under 30 kPa. If the AutoRanged span is 30 kPa (less than 30% of the 160 kPa
maximum Q-RPT span), the measurement uncertainty in pressure is measured pressure x 0.008% to 14.4 kPa (160 kPa
maximum Q-RPT span x 9%) and 0.0012 kPa (160 kPa maximum Q-RPT span x 9% x 0.008%) under 14.4 kPa.
None required, 30 minute temperature stabilization
recommended for best performance from cold power up.
To 1 ppm, user adjustable
5 to 35 °C
± 0.008 % /g maximum, worst axis
Allows operation at ± 20° from reference plane without
significant effect
± 0.005% of reading
STANDARD CLASS PREMIUM CLASS
± 0.008% of reading or
0.0024% of Q-RPT span,
whichever is greater
5
± 0.01% of reading or 0.0030%
of Q-RPT span, whichever is
greater
5
± 0.011 % of reading or
0.0033% of Q-RPT span,
whichever is greater
5
± 0.005% of reading, 0.0015%
of AutoRanged span, or
0.0005% of Q-RPT span,
whichever is greater
± 0.008 % of reading, 0.0024%
of AutoRanged span, or
0.0007% of Q-RPT span,
whichever is greater
± 0.009 % of reading,
0.0027% of AutoRanged span,
or 0.0008% of Q-RPT span,
Base PPC3 pressure controllers include a utility sensor. If a Hi Q-RPT
(see Section 3.2.4) is installed, there is no utility sensor.
Utility sensors are used for pressure control, system monitoring and safety functions.
They are intended for indication only, not to provide reference pressure
measurement. Q-RPTs (see Section 1.2.2.1) are used for reference measurement.
Warm Up Time
Range
Resolution
Precision
1.2.2.3ON-BOARD BAROMETER
The on-board barometer is used only to measure changes in atmospheric
pressure to provide dynamic compensation of the Q-RPT’s atmospheric pressure
offset when using an Axxx (absolute) Q-RPT to make gauge pressure
measurements.
PPC3 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 PPC3 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 PPC3 includes all items indicated in Table 2.
The PPC3 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 PPC3 can also be mounted in a
standard 19 in. rack using the optional rack mount kit.
Minimizing the distance between the PPC3 and the device or system under test will enhance control
performance and reduce pressure setting times.
Ready access to the PPC3 rear panel should be considered to facilitate making and breaking
pressure connections.
Pneumatic and RS-232 connections to RPM4s should be considered if RPM4s are to be used as
external reference pressure measurement devices (see Section 2.3.7).
The Self Purging Liquid Trap (SPLT), if used, should be mounted vertically at the low point of the
connection between the PPC3 TEST(+) port and the test (see Section 2.3.8.1).
If you are using a G15K or BG15K Q-RPT with a Dual Volume Unit (DVU), its location and
connections should be considered (see Section 2.3.8.2).
Support facilities required include:
• An electrical power source of 85 to 264 VAC, 50 - 60 Hz.
• A continuous, regulated pressure supply of clean, dry, non-corrosive gas at PPC3 maximum
control pressure + 10 % (at least 70 kPa (10 psi) in the case of a BG15K Q-RPT) to be connected to
the PPC3 SUPPLY port. Lower gas pressure supply can be used but should exceed the maximum
desired test output pressure by 10 to 20 %.
•A vacuum source of less than 1 psia (7 kPa) and with displacement of at least 3 cfm (90 lm)
if control of pressures under 3 psi (20 kPa) gauge is desired.
2.3 SETUP
2.3.1 PREPARING FOR OPERATION
To prepare PPC3 for check out and operation:
Remove the plastic caps from the PPC3 rear panel pressure connections.
Remove the protective plastic sheet from the front panel display.
Install the rubber feet caps onto the bottom case feet, if desired.
Familiarize yourself briefly with the front and rear panel (see Section 2.3.2).
Check that the PPC3 power switch is OFF.
Connect the supplied power cable to the rear panel power module.
Connect the other end of the power cable to an electrical supply of 85 to 264 VAC, 50/60 Hz.
2.3.4 REMOTE [ENTER/SET P] CONNECTION (FOOTSWITCH
OR OTHER SWITCH)
Connect the optional remote ENTER footswitch, if available or a user supplied switch fitted to
the optional cable (see Section 7.3). Connect the cable to the PPC3 rear panel connection
labeled REMOTE ENTER. Activating the switch is equivalent to pressing the [ENT/SET P]
key on the front panel (see Section 3.1.4).
2.3.5 CONNECTING TO A PRESSURE SUPPLY (SUPPLY
PORT)
Using a pressure connecting hose or tube of appropriate pressure rating, connect the
pressure supply to the SUPPLY port on the rear panel of PPC3. The PPC3 SUPPLY port
connection is 1/8 in. NPT female.
The supply pressure should be equal to the maximum PPC3 control pressure + 10 % (or at
least 70 kPa (10 psi) for a BG15K Q-RPT). Lower gas pressure sources can be used but
should exceed the maximum desired test output pressure by 10 to 20 %.
Never connect a pressure supply greater than 20 % over the maximum control pressure of
the PPC3 model you are using (except models with a BG15K Q-RPT only). Be sure to
connect the pressure supply to the SUPPLY port. Connecting to another port is likely to
damage PPC3.
2.3.6 CONNECTING A VACUUM PUMP (EXHAUST PORT)
For PPC3 to set pressures under atmosphere and/or to reliably set pressure under 20 kPa (3 psi)
gauge (other than zero gauge), a vacuum supply must be connected to the EXHAUST port.
Never connect a pressure supply to or plug the PPC3 EXHAUST port.
To avoid building up pressure on the EXHAUST port or on a vacuum pump connected to
the EXHAUST port, the vacuum source should either be continuously ON or the EXHAUST
port should be bypassed to atmosphere when the vacuum source is OFF. This is because
when a supply pressure is applied to the PPC3 SUPPLY port and the PPC3 is NOT in the
vent ON condition, there may be a constant gas exhaust through the PPC3 EXHAUST port.
To assure optimum pressure control when changing the pressure applied to the EXHAUST
port from vacuum to atmosphere or vice-versa, be sure to change the control reference
setting if the setting is NOT in AUTO mode (see Section 3.5.7.2).
2.3.7 CONNECTING EXTERNAL Q-RPTS IN RPM4 REFERENCE
PRESSURE MONITORS
PPC3 can be connected pneumatically and by RS-232 to one or two RPM4 reference
pressure monitors to use up to four external Q-RPTs (two in each RPM4) as external
reference pressure measurement devices (see Section 3.2.4).
The PPC3 then manages communications and other RPM4 functions to integrate the RPM4
measurement capabilities into the PPC3 system. The RPM4 Q-RPT module’s Self Defense
System (SDS) is used to shut-off RPM4 Q-RPTs from the pressurized system when they are
not in use (see the RPM4 Operation and Maintenance Manual).
As a general rule, making the pneumatic connection between the PPC3 TEST port and the
remote Q-RPT as direct as possible favors good pressure control. As distance, volumes
and restrictions between the PPC3 TEST port and the remote Q-RPT are added, the
possibility of difficulty with pressure control when using the external Q-RPT increases.
To connect a PPC3 to an RPM4 to be used as part of the PPC3 system proceed as follows:
Set up the RPM4 for use as an external device to PPC3 following the instructions in
the RPM4 Operation and Maintenance Manual, Using RPM4 With a PPC3
Controller/Calibration Section.
Using tubing of appropriate pressure rating and a Tee, connect the RPM4 Q-RPT
TEST(+) port to the PPC3 TEST(+) port. The third leg of the Tee is for the connection to
the device or system under test. If there are two RPM4s, Tee the second RPM4 in series
with the first one. The order of the RPM4s on the test line is not relevant.
If an RPM4 Q-RPT will be used in a gauge pressure range of less than 100 kPa (15 psi),
consider connecting the RPM4 Q-RPT module TEST(-) port to the PPC3 TEST(-) port and
to the “low” connection of the DUT if available. This will improve pressure control and
stability when ambient pressure is unstable. If the Q-RPT is an Axxx designation Q-RPT,
this connection should be made but also be left open to atmosphere.
When external Q-RPTs are used with PPC3, the maximum set pressure is the maximum
pressure of the PPC3 controller/calibrator. The maximum pressure of the PPC3 is
determined by the PPC3 controller model or the Hi Q-RPT if one is installed (see Section 1.2.1).
Using a standard pin-to-pin DB-9M to DB-9F RS232 cable, connect COM2 of the PPC3
to COM1 of the RPM4 (see Section 4.2.1.3). If there are two RPM4s, connect COM2 of the
first RPM4 to COM1 of the second RPM4. The order of the RPM4 daisy chain is not
relevant.
Turn ON the PPC3 and RPM4(s).
Press [RPT] on the PPC3 key pad. This causes PPC3 to execute the Q-RPT search
function (see Section 3.3.5). Q-RPTs with whom communication is established will be
shown on the PPC3 display identified by their position (see Table 3).
For PPC3 to identify external RPM4s, the RPM4 COM1 port settings must be:
Baud rate: between 1200 and 19200
Parity: Even
Date bits: 7
Stop bits: 1
If PPC3 is not able to establish communications with RPM4s and their Q-RPTs, check
that the RPM4 COM1 port setting conform to the requirements above. If the COM1 port
settings are correct, check that the correct communications cable is being used
(standard pin-to-pin DB-9M to DB-9F RS232) and is connected to the correct
communications ports.
PPC3 COM2 > 1
st
See the RPM4 Operation and Maintenance Manual for additional information on RPM4
RS232 communications and COM port settings.
2.3.8 CONNECTING TO THE DEVICE UNDER TEST (TEST(+)
AND TEST(-) PORTS)
RPM4 COM1; 1st RPM4 COM2 > 2nd RPM4 COM1
If you are using a self purging liquid trap (SPLT), see Section 2.3.8.1 before proceeding to
connect the device under test.
If the PPC3 has a G15K or BG15K Q-RPT, a dual volume unit (DVU) should be installed for
very low pressure control. See Section 2.3.8.2 before proceeding to connect to the device
under test.
Using a pressure connecting hose or tube of appropriate pressure rating, connect the device or
system to be tested to the PPC3 TEST(+) port. The PPC3 TEST(+) connection is 1/8 in. NPT female.
PPC3 TEST(+) AND TEST(-) PORTS
All PPC3s have a TEST(+) and a TEST(-) port. See Figure 13 for PPC3 internal Q-RPT
TEST port configurations.
The TEST(+) port is connected to Axxx (absolute) Q-RPTs and to the high side of Gxxx or
BGxxx (gauge, bi-directional gauge) Q-RPTs.
The TEST(-) port is connected to PPC3s internal barometer, if present, and to the low side of
Gxxx or BGxxx (gauge, bi-directional gauge) Q-RPTs.
• When operating in absolute mode: The TEST(-) port is left open to atmosphere.
• When operating in gauge or negative gauge mode with a range greater than 50 kPa
(7.5 psi): The TEST(-) port is normally left open to atmosphere. A possible exception is
when the device or system under test is in an ambient pressure that may differ significantly
from the ambient pressure around the PPC3. For example, if the PPC3 is controlling
pressure into DUTs in an environmental chamber, the pressure in the environmental
chamber may be different from ambient pressure around the PPC3. In this case,
connecting a tube from the TEST(-) port to the inside of the chamber may improve
measurement results. If the Q-RPT in use is an Axxx Q-RPT, this tube must be left open to
the environment so t hat the pressure inside cannot deviate too far from ambient. When using
an Axxx Q-RPT, if this tube is connected to t he lo w o r re f er en c e si d e of DU Ts , b e s ur e to
open to the local environment as well.
•When operating in gauge or negative gauge mode with a range less than 50 kPa (7.5 psi):
As a general rule, it is preferable to connect the PPC3 TEST(-) port(s) directly to the low or
reference side of the device under test to assure that these are at the same pressure.
When using an Axxx Q-RPT, this connection must also be open to atmosphere. When using
a Gxxx or BGxxx Q-RPT, it is preferable that this connection not be open to atmosphere.
Do not apply pressure to the TEST(+) port without having a pressure supply equal to or
greater than the applied pressure connected to the SUPPLY port. When controlling
pressure to the TEST(+) port externally, do not cause the pressure to change at a very
rapid rate. For example, do not vent suddenly by opening an external valve. Internal
damage to the PPC3 may result.
Do not connect a pressure supply to the TEST(-) port. The pressure applied to this port
should be maintained at atmospheric pressure (between 70 and 110 kPa (10 and 16 psia)).
Exceeding these limits may damage a Gxxx or BGxxx Q-RPT and/or the PPC3’s
on-board barometer.
Operating the PPC3 connected to a system with liquid contaminants without taking
proper precautions to purge the system and test line may cause contamination of the
PPC3 that will require non-warranty service.
Minimizing the length of the test connection tubing will enhance control performance and
reduce pressure setting time. For normal operation, the total volume of the device or
system under test including connecting tubing should be less than 1 000 cc (60 in
3
)
up to 2 000 kPa (300 psi) and less than 500 cc (30 in3) above 2 000 kPa (300 psi).
Minimizing the length of the test connection tubing and restrictions in connections will
enhance control performance and reduce pressure setting time.
PPC3 pressure control will not operate properly if there are excessive leaks in the test
system. In general, the maximum acceptable leak rate for optimal PPC3 automated pressure
control operation and to assure in tolerance measurements with default pressure control
parameters is ± 0.5 % of set pressure/minute. In DYNAMIC CONTROL mode, to handle
higher test system leak rates, increase the hold limit using CUSTOM CONTROL (see
Section 3.4.6.1).
PPC3 pressure control may be adversely affected if the test connection tubing is too
restrictive. For optimum results, the inner diameter of the connecting hose should be
> 1.75 mm (0.07 in.), or more.
2.3.8.1 INSTALLING A SELF PURGING LIQUID TRAP (SPLT)
The SPLT (optional) is intended to collect and exhaust liquid or other
contaminants that may be present in the device or system under test so that they
do not return to contaminate the PPC3.
The SPLT is installed in the TEST(+) connection line at a low point between
PPC3 and the device or system under test. If the PPC3 system includes external
Q-RPTs in RPM4(s), the RPM4s should be connected on the PPC3 side of the
SPLT.
See the SPLT Operation and Maintenance manual for more complete
instructions on SPLT installation.
2.3.8.2 INSTALLING A DUAL VOLUME UNIT (DVU), G15K AND
BG15K Q-RPTS
To achieve in tolerance pressure control with the very low range of the G15K and
BG15KQ-RPTs, a PK-PPC-BG-DVU dual volume units should be installed in-line
on the TEST(+) and TEST(-) ports. The DVU includes two thermally isolated
volumes installed in the test line to improve control stability.
See the PK-PPC-BG-DVU instruction sheet for additional information on its
installation.
2.3.9 THE VENT PORT
The PPC3 VENT port is the system vent to atmosphere point used to set zero gauge pressure as
well as to obtain Q-RPT measurements of atmospheric pressure. The PPC3 on-board
barometer, if present is connected to the VENT port. 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 PPC3 reference pressure measurements
to operate normally.
The PPC3 VENT port fitting is 10-32 UNF.
NEVER plug, obstruct or connect a supply pressure to the PPC3 VENT port. This may
adversely affect GAUGE mode operation and AutoZeroing functions.
2.3.10 CHECK/SET SECURITY LEVEL
PPC3 has a security system based on user levels. By default, the security system is set to
“low”, which includes certain access restrictions, and there is no password required to
change the security level. See Section 3.5.5.5 for information on the security level system.
As part of the PPC3 startup, determine the security level that is appropriate for the PPC3 and
set a password if desired.
PPC3 is delivered with the security level set to “low” to avoid inadvertent altering of critical
internal settings but with access to changing security levels unrestricted. It is recommended
that the low security level be maintained at all times and password protection be
implemented if control over setting of security levels is desired.
2.3.11 TURN OFF ABSOLUTE AND NEGATIVE GAUGE MODE
(AXXX RPT)
If your PPC3 has an Axxx (absolute) Q-RPT, it is able to operate in gauge,
negative gauge and absolute measurement modes (see Section 3.3.3).
If the PPC3 will be used only in gauge mode, the other measurement modes can
be turned off so they are no longer accessible. This can avoid confusion and/or
accidental use of the wrong measurement mode. See Section 5.2.5 for complete
information on turning off absolute and negative gauge measurement modes.
Actuate the power switch on the PPC3 rear panel. Observe the front panel display as PPC3
initializes, error checks and goes to the MAIN RUN screen (see Section 3.1.1).
PPC3 power-up condition is Internal, Hi Q-RPT or utility sensor active, VENT ON unless the
pressure measured by the Hi Q-RPT is more than 20 kPa (3 psi) away from standard
atmospheric pressure.
If the PPC3 fails to reach the MAIN RUN screen, service is required. Record the sequence
of operations and displays observed.
If the PPC3 has an Axxx (absolute) Q-RPT or a utility sensor (IuH), check that it
operates properly in absolute mode.
If the PPC3 is not vented (VENT LED OFF), press the [VENT] direct pressure
control key to vent the PPC3 (VENT LED ON) (see Section 3.1.3).
Using the [RANGE] function key to change ranges if necessary and select the
Axxx (absolute) Q-RPT DF range (see Section 3.3.1). Press the [MODE]
function key and select <absolute> mode (see Section 3.3.3). Use [UNIT] to
change the pressure unit if desired (see Section 3.3.2).
Observe the current value of atmospheric pressure. Check that the value agrees
with the local value of atmospheric pressure. Repeat this process for all the
Axxx (absolute) Q-RPTs and or the utility sensor in the PPC3 system. Check
that the values of atmospheric pressure measured by the different devices agree
with each other within PPC3 or RPM4 measurement tolerances as applicable
(see Section 1.2.2.1, 1.2.2.2). If they do not agree within tolerances, the PPC3
or RPM4 Q-RPT may need calibration or repair.
2.4.2.2 CHECKING GAUGE MODE PRESSURE MEASUREMENT
If the PPC3 is not vented, press the [VENT] direct pressure control key to vent it
(see Section 3.1.3).
Press the [MODE] function key and select <gauge> mode. Change the
pressure unit if desired (see Section 3.3.3).
Observe that, within ten seconds, zero is indicated. It is normal for PPC3 to indicate
a value other than zero for up to ten seconds when first entering gauge mode.
Using the [RANGE] function key to change ranges, observe that zero is
indicated for each Q-RPT within 10 seconds. It is normal for PPC3 to indicate a
value other than zero when vented when gauge mode is first entered or ranges
are changed. After about ten seconds, the VENT LED should flash and zero
should be indicated. If this does not occur, check that the AUTOZERO function
is O N (see Section 3.5.1). If AUTOZERO is ON and the displayed pressure will not
zero when vented in gauge or bi-directional gauge measurement mode, PPC3 may
need repair.
If desired, perform a leak check of the test system (see Section 3.3.9).
2.4.4 PURGE
If an SPLT is included and installed in the test line and the Device Under Test (DUT) may be
contaminated with liquids, perform a purge of the DUT (see Section 3.3.8). The PURGE function
must first be activated (see Section 3.5.7.4). This will rid the DUT of contaminating liquids.
Operating the PPC3 connected to a system with liquid contaminants without taking
proper precautions to purge the system and test line may cause contamination of the
PPC3 that will require non-warranty service.
2.4.5 CHECK PRESSURE CONTROL OPERATION
Select a pressure range using [RANGE] (see Section 3.3.1).
Press [SETUP], <6control>, <2dynamic> (see Section 3.4.6). Then [ESC] back to the
MAIN RUN screen.
Press [ENT]. Key in a target pressure within the active range and press [ENT] again
(see Section 3.3.10).
Verify the maximum pressure rating of the system connected to the PPC3 TEST(+) port
before entering a target pressure. Do not enter a target pressure greater than the
pressure rating of the system connected to the PPC3 TEST(+) port.
PPC3 should set the target pressure and indicate Ready (see Section 3.2.2) continuously in
15 to 60 seconds. If it does not, see Section 6 to troubleshoot.
2.5 SHORT TERM STORAGE
The following procedure is recommended for short term storage of PPC3:
Vent the PPC3 test pressure.
Turn the power OFF using the rear panel power switch. Shut OFF or disconnect the pressure supply. Shut OFF or disconnect the vacuum supply. Be sure the pressure supply is disconnected or the
vacuum pump is bypassed from the PPC3 EXHAUST port before turning OFF the vacuum pump.
PPC3 is designed to offer a practical balance between simple, straight forward operation and
the availability of a wide variety of advanced functions with a high level of operator discretion.
The local operator interface is through a 2 x 20 display, a function/data keypad, a cursor
control pad and direct pressure control keys.
Remote communication is by RS232 (COM1) or IEEE-488. See Section 4 for specific
information on remote communication.
3.1.1 MAIN RUN SCREEN
The PPC3 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 PPC3 to set and read pressures.
It provides complete information on the system’s current configuration and operating status.
Figure 3 and its legend table summarize the PPC3 MAIN RUN screen fields and their functions.
PPC3 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 3.5.5.1).
The PPC3 has a function/data 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 (see Section 3.2.7). The
name of the function is on the bottom half of
the key. These keys enter numerical values
when editing.
2. The Editing and Execution keys are for
starting and suspending command execution,
cursor control in menus and editing entries.
Figure 4. Keypad Layout
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 3.4). The SPECIAL menu is for
functions that are not generally used as a
part of day to day operation (see Section
3.5). These keys enter numerical values
when editing.
Pressing the [ENT/SET P] key generally causes execution or forward movement in the menu
tree. Pressing [ENT/SET P] from the MAIN RUN screen allows an automated pressure
control command to be given.
Pressing the [ESC] key moves back in the menu tree and/or causes execution to cease or
suspend. Pressing [ESC] repeatedly eventually returns to the MAIN RUN screen and, from
there, allows momentary viewing of the PPC3 introduction screen.
Pressing the [+/-] key changes a numerical sign when editing. It also toggles through
multiple screens when available and is a shortcut to a momentary display of the active
RANGE from the MAIN RUN screen.
Pressing the [
], [], [] and [] keys allows reverse, forward and up, down cursor
movement when editing data entry or moving in menus.
Some screens go beyond the two lines provided by the display. This is indicated by a
flashing down arrow in the second line of the display. Press the cursor control 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.
The direct pressure control keys provide direct manual control of pressure increase,
decrease, jog and vent. They can be useful in adjusting pressure when automated pressure
control to a target value is not needed. The jog keys are also used to adjust the target
pressure during active pressure control.
The [
] and [] direct pressure control keys interrupt and override automated pressure
control.
Pressing the [VENT] key causes PPC3 to control pressure to near atmospheric pressure and
then open the system vent valve (see Figures 12 and 13). On-going execution of the vent
function is indicated by lighting a RED LED just above the [VENT] key. Completion of the
vent process is indicated by the Ready/Not Ready indicator light becoming GREEN with the
vent RED LED still lighted. The vent valve remains open until the [VENT] key is pressed
again, another direct pressure control key is pressed, or an automated pressure control
command is given.
Pressing the [
decrease at the slow slew rate. Holding the [FAST] key pressed while pressing the [
] key causes the pressure increase or decrease speed to change from slow to fast.
or [
Pressing the [
] and [] direct pressure control keys causes pressure to increase or
]
] and [] direct pressure control keys causes the pressure to jog or step by
a fixed amount. During active pressure control, they cause the target pressure to be
changed by the fixed amount. One press causes one step. The approximate value of the step
is set automatically depending on the current active PPC3 range. The value can be adjusted
using [SETUP], <3jog> or pressing both the up and down jog keys simultaneously (see
Section 3.4.3).
Pressing the up and down pressure jog keys ([] and []) simultaneously is a
shortcut to the jog step size adjustment menu.
3.1.4 REMOTE [ENT/SET P] FOOTSWITCH
The optional remote ENTER function is a switch that duplicates the function of the front panel
[ENT] key. The remote ENTER function is serviced by a connector on the PPC3 rear panel
labeled REMOTE ENTER. An optional footswitch is available to activate remote entry hands
free or a user supplied switch may be used. See Section 7.3 for information on remote
ENTER switch wiring.
The remote ENTER feature can be particularly convenient when running AutoTests
(see Section 3.3.6) in which using a footswitch to [ENT] allows hands free operation.
PPC3 is equipped with a variable frequency tone device to provide audible feedback and
alarms. The beeper is used for the following indications.
Valid key press Brief beep. Choice between three frequencies
or NO sound is available (see Section 3.5.5.2).
Invalid key press Descending two tone “blurp”.
Leak check completed Three two second beeps (see Section 3.3.9).
Upper or lower limit exceeded Intermittent one second beeps (see Section 3.4.4)
External device not connected Eight second high frequency beep (see Section
2.3.7)
Pmax! (overpressure limit) exceeded Eight second high frequency beep (see Section
3.4.4.1).
AutoTest reading in tolerance/out of Ascending triad/descending triad (see Section
tolerance reading 3.3.10).
3.2 GENERAL OPERATING PRINCIPLES
3.2.1 AUTOMATED PRESSURE CONTROL
PPC3 automated pressure control provides automated adjustment and control of pressure to
a user designated target value. Pressing [ENT/SET P] from the MAIN RUN screen allows a
pressure control target value to be entered and executed. Pressing [ESC], a direct pressure
control key or a function key causes active pressure control to be interrupted. Sending a
remote command when in local mode also interrupts pressure control.
PPC3 supports two pressure control modes to meet different pressure setting and controlling
requirements: dynamic and static. Pressure control parameters for each control mode are
automatically set to optimal default values for the operating PPC3 range when the range is
selected or AutoRange is used (see Section 3.3.4). Control parameters can be customized
using the [SETUP], <6control> function (see Section 3.4.6).
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 maintained.
Stability LimitA 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
See this section, Dynamic Control and Static Control for a detailed explanation of each
control mode and its advantages, the default control parameters and the control
customization options.
PPC3 is idle (control not active).
Dynamic Control
Dynamic control mode is designed to set the pressure to the target value and control
continuously to keep pressure within the hold limit and as close to the target value as possible
(see Figure 6). The advantage of this control mode is that the final pressure achieved is the
same as the target value. The maximum value of the control error is equal to the hold limit. The
average value of the control error is generally much smaller than the hold limit.
During dynamic pressure control, the hold limit is active. If the pressure goes outside of the
hold limit, a Not Ready condition occurs. See Tables 6 and 7 for default hold limit values and
Section 3.3.6 to customize the hold limit.
Figure 6. Dynamic Pressure Control Operation
Static Control
Static control mode is designed to set the pressure near the target value and then interrupt
active control to allow pressure to stabilize naturally within the hold limit. The advantage of
this control mode is that pressure can be set and/or measured within a defined limit of a
target without interference from the pressure control system. In a system without excessive
leaks, the pressure stability achieved may be greater than the stability with which the
pressure control system can actively control pressure. Using static control to control
pressure near the desired set point and then measuring back the stabilized pressure without
interference of the control function can allow control errors to be completely eliminated.
However, the final pressure achieved is not equal to the target value.
During static pressure control, the hold limit is active. If the pressure goes outside of the hold limit,
a Not Ready condition occurs (see Section 3.2.2) and pressure is readjusted to the target value
(see Tables 6 and 7 and Section 3.3.6 for setting the hold and stability limits to user defined values).