Halma ALICAT SCIENTIFIC PCD User manual

OPERATING MANUAL
FOR DUAL-VALVE PRESSURE
CONTROLLERS
Models PCD · PCDS · PCD3 · PCD3S · IVCD · EXTSEN

2 Introduction
Thank you for purchasing your pressure controller.
If you have any questions, or if something is not working as expected,
please contact us. We are eager to help you in any way possible.
Contact Information
Alicat Scientific World Headquarters
7641 N Business Park Dr., Tucson, AZ 85743 USA
[e-mail] • alicat.com • [phone]
India
[e-mail]
Halma India Pvt. Ltd.
Plot NO. A-147, Road No. 24,
Next to Spraytech Circle
opp. Metropolitan Company,
Wagle Industrial Estate
Thane-West
Mahārāshtra 400 604
[phone]
China & SE Asia
[e-mail]
alicat.com.cn
2nd Floor, Block 63, No. 421,
Hong Cao Rd,
Shanghai 200233
PRC
[phone] ext. 801
Europe
[email protected]om
Geograaf 24
6921 EW Duiven
The Netherlands
+31 (0) 26 203.1651
Recalibrate your pressure controller every year.
Annual calibration is required to ensure the continued certainty of readings,
and to extend the Limited Lifetime Warranty (page 45). Fill out the
Service Request Form at alicat.com/service,or contact us directly when
it is time to send in your device for recalibration.
Serial #: Next Calibration:
This device comes with a NIST-
traceable calibration certificate.
This device conforms to the European Union’s
Restriction of Use of Hazardous Substances in Electrical
and Electronic Equipment (RoHS) Directive 2011/65/EU.
This device complies with the requirements of the Low
Voltage Directive 2014/35/EU and the EMC Directive
2014/30/EU and carries the CE Marking accordingly.
This device complies with the requirements of the
European Union’s Waste Electrical & Electronic
Equipment (WEEE) Directive 2002/96/EC
Rev.  • 2020.11.06 • DUAL-VALVE PRESSURE CONTROLLER operating manual

DUAL-VALVE PRESSURE CONTROLLER operating manual 3
Introduction
Your new pressure controller has a variety of innovative features:
• 1000 readings per second ensures high resolution data.
• Backlit display with adjustable contrast is easy to read in
direct sunlight. In dimly lit areas, press the bottom-center
logo to turn on the backlight (see page 6).
• Ability to control gases and liquids to accommodate for a wide
range of pressure control applications, when properly configured.
• Data logging to your PC over a serial data connection to capture all
pressure data, for logging and analysis purposes (see page 29).
Please take the time to find and read the information for your specific
device. This manual covers the following Alicat Scientific instruments:
• PCD-Series absolute, gauge, and dierential pressure controllers
• PCD3-Series external-sensing pressure controllers
• IVCD-Series integrated vacuum controllers
This includes devices configured with corrosion-resistant materials
(PCDS, PCD3S), devices with a remote-sensing line (PCD3, PCD3S), a
remote sensor (EXTSEN), large pneutronics valves (PCPD), “hammer-
head” dual valve configurations (PCHD, PCPHD, PCRHD), and most
combinations of these options.
This also includes devices labeled as approved for CSA Class 1 Div 2 and
ATEX Class 1 Zone 2 hazardous environments. See page 44 for Special
Conditions regarding the use of CSA/ATEX labeled devices.
Recalibration
Your pressure controller is a precision device, and an annual calibration
is strongly recommended.
A yearly recalibration has several benefits:
• It ensures that your unit is functioning according to specification.
• Contamination may cause the instrument to measure improperly.
Recalibration ensures the instrument is clean and free of debris.
• Recalibration maintains your LIFETIME WARRANTY (see page 45).
Sending your unit in for recalibration is quick, easy, and inexpensive.
Please keep the original box to return your Alicat instrument for recali-
bration. For more information regarding recalibration, see page 37.

4 Table of Contents
Contents
Introduction 3
Recalibration 3
Getting Started 6
The Pressure Controller Display 7
Status Messages 7
Mounting 8
Process Ports 8
Filters 8
Operating Pressure 8
Connecting Plumbing 8
Applications 9
Using Alicat Pressure Instruments with Liquids 10
Dual-Valve Integrated Vacuum Controllers (IVCD) 10
Power and Signal Connections 11
RS-232 or RS-485 Digital Signals 12
Engineering Units 13
Option: Color TFT Display 14
Navigation & Customization 15
Main Menu 15
Taring 15
Control Menus 16
Changing the Setpoint 18
Establishing Setpoint Limits 19
Setpoint Ramping 20
Adjusting the Closed Loop Controller 22
Troubleshooting valve performance with PDI tuning 23
Device Information 24
Basic Configuration Menu 25
Engineering Units 25
Advanced Setup 26
Display Setup 26
Sensor Setup 27
Configuring Serial Communications 28

DUAL-VALVE PRESSURE CONTROLLER operating manual 5
Contents
Serial Communication 29
Establishing Communication 29
Polling Mode 30
Streaming Mode 30
Taring 31
Collecting Pressure Data 31
Commanding a New Setpoint 32
Sending Setpoints as Floating Point Numbers 32
Sending Setpoints as Integers 32
Quick Command Guide 33
Troubleshooting 34
Maintenance 37
Cleaning 37
Recalibration 37
Engineering Units 38
Pinouts 39
8-Pin Mini-DIN (Default) 39
Locking Industrial Connector Pinout 40
9-pin D-Sub Connector Pinouts 41
M12 Connector Pinouts 42
15-Pin D-Sub Connector Pinouts 43
Additional Information for CSA and ATEX Approved Devices 44
Limited Lifetime Warranty 45

6 Getting Started
Getting Started
Getting to Know Your Dual-Valve Pressure Controller
Connectors and Buttons
The drawings below represent a typical configuration of a dual-valve
pressure controller.
Your device’s appearance and connections may differ.
+0.0000
MENU
PSID TARE
SETPT
+0.0000
Dif Press
PSID
+0.0000
I/O Port
(shape varies)
DC
In
Light
Switch
Controls
Inlet
Valve
Outlet
Valve
Display
Flow
Body
PCD3 Units: Remote sensor
port in the back; process port
in the front.
Differential PCD: Process
port in the back; Differential
sensors in the front.
Optional: Differential
Pressure Sensor Ports Process Port
Supply &
Exhaust Ports
Mounting
Holes

DUAL-VALVE PRESSURE CONTROLLER operating manual 7
The Pressure Controller Display
The figure below identifies the various features of the main pressure
controller display. Press the button behind the Alicat logo to toggle the
backlight on and o.
Live data is measured 1000 times per second, and is typically displayed
10 times per second on the device’s LCD screen.
Device engineering units are used by the controller in its serial commu-
nications and calculations. These can optionally be dierent from the
button engineering units, which are the units being displayed. These
can be individually configurable using the front display (page 25).
Chooses the pressure
engineering units (page 25).
TARE PRESS tares the pressure
reading on the device. Ensure
the device is exposed to
atmospheric pressure when
this is performed. Tares are
not available on absolute
pressure () devices.
SETPT sets the pressure
control setpoint (page 18).
MENU enters the menu
system (page 15).
The button under the Alicat
logo toggles the backlight
(see page 26 for more
display options).
Status Messages
ADC Analog-digital converter error
EXH Exhaust mode active
HLD Valve hold active
LCK Front display is locked
POV Pressure over range of device

8 Getting Started
Mounting
All pressure controllers have mounting holes under the base for convenient
attachment to flat panels. No straight runs of pipe are required upstream
or downstream. Standard controllers are position insensitive and can be
mounted in any orientation.
▲ Caution: Pressure controllers that use large Rolamite valves (PCRD,
PCRD3, PCRDS) should be mounted with valves oriented vertically
(right-side up). for other orientations, contact support (page 2).
Process Ports
Your pressure controller has been shipped with plastic plugs fitted into its
ports. To lessen the chance of contaminating the stream, do not remove
these plugs until you are ready to install the device.
Standard pressure controllers have female inlet and outlet ports. Welded
VCR® and other specialty fittings may have male connections.
• For connections without face seal fittings, use thread-sealing
Teflon tape to prevent leakage, but do not wrap the first two
threads. This will help prevent tape getting into the stream.
• No tape is needed for face seal fittings.
• When changing fittings, carefully clean the port threads.
! Warning: Do not use pipe dopes or sealants on the process
connections, as these compounds can cause permanent
damage to the controller should they get into the stream.
Filters
We recommend in-line sintered filters to prevent large particulates from
entering the pressure controller, even though they may increase pressure
drop. Suggested maximum particulate sizes are as follows:
PCD/PCPD/PCHD/PCD3: 20 microns PCRD/PCRD3: 40 microns
Operating Pressure
Controllable Pressure Burst Pressure,
≤500 PSI devices*
Burst Pressure,
>500 PSI devices*
102.4% of full scale pressure 300% of full scale pressure 150% of full scale pressure
*Exceeding burst pressure will permanently damage the internal pressure sensor.
Connecting Plumbing
Your device can be configured to regulate positive pressure, vacuum, or
both. Connect it so that flow travels as indicated by the arrow, usually left
to right, from the front of the device.

DUAL-VALVE PRESSURE CONTROLLER operating manual 9
Applications
Gauge and Absolute Pressure Control Application
The port on the face of the unit is connected to the closed volume where
you want to control pressure. The valve on the supply side will open to
increase the pressure in the closed volume, and the valve on the exhaust
side will open to decrease pressure.
Remote-Sensing Pressure Control Application
PCD3-Series models sense and control the pressure at a point in the
system outside of the pressure controller. An additional NPT port on the
back is connected directly to the absolute pressure sensor in the device.
The pressure sensor is isolated from the flow path in this configuration.
Dierential Pressure Control Application
PCD-PSID Series pressure devices monitor and control the dierential
pressure between two points in the system. These devices have two ports
located on the front face of the unit for connection to two points in the
system where the dierential pressure is measured from. The upstream
port is for the higher of the two pressures, and the downstream port is for
the lower pressure. The process port is on the back of the unit. In these
devices, the flow path through the device is not connected to either leg
of the dierential pressure sensor.
Gas Supply
or Atmosphere
Alicat
Controller
Pressure
Regulator
Flow in both directions
Closed Volume
at Setpoint Pressure
Exhaust to
Vacuum or
Atmosphere
Gas
Supply
Alicat
Controller
Flow
Exhaust
Process line
(port is in the back of the unit)
P1 Sensor (no flow)
P2 Sensor (no flow)
Process/Device under Test
P P2
Pressure
Regulator
Gas Supply
or Atmosphere
Alicat
Controller
Flow in both directions
Remote Sense Line (no flow)
Located behind the unit
Closed Volume
at Setpoint Pressure
Exhaust
Pressure
Regulator

10 Getting Started
Using Alicat Pressure Instruments with Liquids
All of these pressure devices may be used with chemically-compatible
liquids, but a few warnings must be taken into account:
1. Water is about 50 times more viscous than air. This is important
when sizing a pressure controller, as this significant increase in
viscosity requires a larger valve to reach expected flow rates. For
example, a PC-series pressure controller sized to flow up to 25 
of air will be limited to roughly 0.5  of water (or similar fluid).
2. The factory PID tuning terms are established using air. It may be
necessary to adjust the PID tuning parameters if you will be using
a controller with liquid. Find more information at alicat.com/PD2I,
or contact us (page 2) to help you through this tuning process.
▲Caution: Please check with Alicat before using
your pressure controller with liquids unless
specifically ordered for this purpose.
Dual-Valve Integrated Vacuum Controllers (IVCD)
IVCDs are similar to our PCD-Series absolute pressure controllers in
functionality and in the navigation menu available on the screen. IVCD
devices are used in applications where precise control of vacuum is
required, and are available with the following sensor packages:
• 10 Torr absolute pressure
• 100 Torr absolute pressure
• 1000 Torr absolute pressure
• Dual-sensor package
which integrates a 1000
Torr and a 10 Torr sensor,
for increased turndown
Integration of the vacuum sensor,
control valve, and PID algorithm
in a single device eliminates the
need for an external vacuum
sensor and throttle valve in your
system. These devices often
come with ⁄-20 SAE ports by
default, but they can be ordered with welded VCR®, compression, or
VCO® fittings if required. Process port sizes may change depending on
the valve on your device.
An Integrated Vacuum Controller (IVCD) device
with PCA valves.Note the process port in front.