Halma ALICAT LC Series User manual

OPERATING MANUAL
FOR LIQUID FLOW
CONTROLLERS
Models LC · LCR · LCS · LCRS

2 Introduction
Thank you for purchasing your liquid flow 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
World Headquarters,
Tucson, Arizona, USA
[e-mail]
alicat.com
7641 N Business Park Dr.,
Tucson, AZ 85743 USA
[phone]
Europe
[email protected]om
Geograaf 24
6921 EW Duiven
The Netherlands
+31 (0)26 203.1651
China & SE Asia
[e-mail]
alicat.com.cn
2nd Floor, Block 63, No. 421,
Hong Cao Rd,
Shanghai 200233
PRC
[phone] ext. 801
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]
Recalibrate your liquid flow controller every year.
Annual calibration is necessary to ensure the accuracy of
readings, and extend the Limited Lifetime Warranty. Fill out
the Service Request Form at alicat.com/service, or contact us
directly when it is time for recalibration.
For devices ordered with CSA, ATEX, ISO 17025, or other certi-
fications, please visit alicat.com/certifications. For information
about our limited lifetime warranty, visit alicat.com/warranty.
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
DOC-MANUAL-LC Rev 1, 2021.05.26
LC-0.5CCM
LC-2CCM

2021.05.26  REV.   LIQUID FLOW CONTROLLER OPERATING MANUAL 3
Introduction
Your new flow controller has a variety of innovative features:
• Control pressure while monitoring volumetric flow rate. Set the
closed loop control algorithm to pressure control, page 28.
• 1000 readings per second guarantees high resolution data,
page 15.
• Monitor live pressure and temperature during flow control,
page 6.
• Backlit display with adjustable contrast is easy to read even in
direct sunlight. In dimly lit areas, press the logo to turn on the
backlight, page 18.
• Connection to a computer for control and data logging to capture
all flow and pressure data for logging and analysis, page 19.
This manual covers the following instruments:
• LC-Series: liquid flow controllers
• LCS-Series: anti-corrosive liquid flow controllers
Using Laminar Liquid Flow Devices
THE DEVICE IS ONLY CONFIGURED FOR ONE TYPE
OF LIQUID, AND WILL ONLY FUNCTION PROPERLY
WHEN USING THAT ONE LIQUID.
By default, liquid devices are configured only for use
with pure water, such as distilled, de-ionized, Type
I (Ultrapure), Type II, and Type III. If a device is
used for any liquid other than the liquid it was
specifically engineered for, readings will be
incorrect
Minimize contaminants and liquid variations.
For water devices, DO NOT use tap water
or water with any biological components,
minerals, or oils. Any of these substances
will aect the viscosity of the liquid, leading
to inaccurate flow measurements. More
importantly, these impurities will quickly
build up in the laminar flow zone, cause
corrosion, and degrade the measurement
accuracy of the device.
For support or questions regarding the use or
operation of this device, please contact us using
the information on page 2.
Alicat oers countless combinations of device sizes, acces-
sories, connections, and configurations. These custom solutions
are oered to meet a variety of application challenges brought forth
by users pushing the boundaries of our standard oerings.
If you have an idea for a new process or a challenging application,
contact Alicat for specialized engineering and application support.
LCR-5LPM

4 Table of Contents
Contents
Introduction 3
Quick Start Guide 5
Getting Started 6
Getting to Know Your Liquid Flow Controller 6
The Liquid Flow Controller Display 6
Status Messages 6
Mounting 6
Filters 6
Device Ports 7
Operating Pressure 7
Bleed Ports 7
Power and Signal Connections 8
Analog Signals 8
Displaying Live Flow Data 9
Option: Collecting Totalized Flow Data 10
Dispensing in Batches 10
Repeating a Batch 10
Pausing or Canceling a Batch 11
Control 12
Changing the Setpoint 12
Adjusting Setpoint with an IPC 12
Setpoint Setup 12
Using Autotare 12
Changing Between Setpoint Sources 12
Setpoint with an Idle Modbus RTU Connection 12
Managing Setpoint on Power Up 12
Establishing Setpoint Limits 12
Control Loop 13
Changing the Controlled Variable 13
Adjusting the PD/PDF or PD²I Control Algorithms 13
Troubleshooting Valve Performance with PID Tuning 14
Limiting Flow while Controlling Pressure 14
Using a Control Deadband for Pressure Control 14
Setpoint Ramping 15
Setting the Ramp Rate 15
Ramping Options 15
Displaying Valve Drive Percentage 15
Device Information 16
Setup 17
Sensor Setup 17
Choosing Engineering Units 17
Flow and Pressure Averaging 17
Zero Band 17
Configuring Serial Communications 17
Unit ID 17
Modbus RTU Configuration 17
Baud Rate 18
Display Setup 18
Main Screen Options 18
Screen Lighting 18
Display Rotation 18
Advanced Setup 18
Serial Communication 19
Establish Communication 19
Alicat’s Serial Terminal Application 19
Modbus RTU Communication 19
Serial Streaming vs. Polling 19
Polling Mode 19
Streaming Mode 20
Taring 20
Collecting Flow Data 20
Quick Command Guide 21
Troubleshooting 22
General Use 22
Flow Readings 22
Serial Communications 23
Maintenance 23
Reference Information 24
Engineering Units 24
Pinouts 25
8-Pin Mini-DIN (Default) 25
Locking Industrial Connector Pinout 25
9-Pin D-Sub Connector Pinouts 26
15-Pin D-Sub Connector Pinouts 27
M12 Connector Pinouts 27

2021.05.26  REV.   LIQUID FLOW CONTROLLER OPERATING MANUAL 5
+0.00
+0.00 +22.73
CCM MENU
PSIG ¤C SETPT
+0.00
Volu Flow
CCM
Water
+0.00
I/O Port
(shape varies)
DC
In
Light
Switch
Controls Valve
Display
Flow
Body
Process
Connections
Mounting
Holes
Bleed
Ports
Quick Start Guide
Setup
• Connect your liquid controller. Ensure
that flow will pass through your device in the
same direction as the arrow on the flow body
(usually left to right).
• Choose your engineering units. You can
choose the measurement units by selecting
MAIN MENU → SETUP → Sensor → Engineering
Units (page 17).
Operation: Flow Verification
• Monitor live volumetric flow, temperature,
and pressure readings. Readings are
updated and displayed on your device in
real time (page 15).
• (Optional) Capture totalized readings. The
totalizer option displays the total flow that has
passed through the device since the last time
the totalizer was reset. If your device has a
totalizer, press NEXT from the main live data
display to access the totalizer (page 10).
Connectors and Buttons
The drawing to the right represents a typical
configuration of a standard liquid flow controller.
Your liquid flow controller’s appearance and
connections may differ. page 3has more
examples.
Backlight
The monochrome display comes equipped with
a backlight. To toggle the backlight power,
press the logo on the front of your device.
For optional color TFT displays, pressing this
button will turn o the display to conserve power
(page 9).
Maintenance and Care
• Liquid flow controllers require minimal
cleaning and maintenance when flowing
clean liquids (page 23).
• Calibrate your liquid flow controller annually.
To schedule a calibration, please contact
support (page 2).
This LC-10CCM model liquid flow
controller is a typical device. The
flow body and the valve sizes
can vary significantly.

6 Getting Started
Getting Started
Getting to Know Your Liquid Flow Controller
The Liquid Flow Controller Display
The figure to the right identifies the various features of the flow meter display.
Highlights pressure in the center of the device.

Highlights temperature in the center of the device
Opens a menu to set the flow or pressure control setpoint (page 12).
Highlights volumetric flow rate in the center of the device.
MENU enters the main menu system.
NEXT accesses the optional flow totalizer (page 10).
Toggles the backlight.
Status Messages
Status messages are shown to the right of the main readout number. In the example to
the right the OVR message shows that the totalizer rolled over to zero.
ADC Analog-digital converter error
EXH Exhaust mode active
HLD Valve hold active
LCK Front display is locked
OVR Totalizer rolled over to zero
POV Pressure over range of device
TMF Totalizer missed out-of-range flow
TOV Temperature over range of device
VOV Volumetric flow over range of device
Mounting
Liquid flow controllers do not require straight runs of pipe upstream or downstream. Most
flow controller models can be mounted in any position, including upside-down. All liquid
flow controllers use media-isolated sensors that must be tared after changing orientation.
✓ Note: If air bubbles are continuously introduced to the flow upstream of the device,
the device may be mounted ue down to prevent bubbles from being trapped in
the pressure sensor ports. Tare the device after changing its position or orientation.
! Warning: If the device has been installed upside down, avoid using the bleed screws
as liquid may leak into the electronics housing and cause permanent damage that is
not covered by the warranty.
▲
Caution: Flow controllers that use large Rolamite valves should be mounted with their
valve oriented vertically (right-side up). If another orientation is desired, please contact
support.
Filters
When pressure drop is not a concern, use in-line sintered filters to prevent large particulates
from entering the flow body of the controller. Suggested maximum particulate sizes are
as follows:
• 20 microns for units with flow ranges ≤ 100 CCM.
• 40 microns for units with flow ranges >100 CCM.
✓
Note: Avoiding long runs of small-diameter tubing upstream or downstream of the
device will reduce liquid hammer.
The main display. Note the button
behind the logo, which toggles the
device backlight.
The main display with a PSID
(PSI-differential) pressure reading.

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Device Ports
Your flow controller has been shipped with plastic plugs fitted into its ports. To lessen
the chance of contaminating the flow stream, do not remove these plugs until you are
ready to install the device.
Standard liquid flow controllers have female inlet and outlet ports. Welded VCR® and
other specialty fittings may have male connections.
• If you are using a fitting that does not have a face seal, use thread-sealing Teflon tape to
prevent leakage around the port threads, but do not wrap the first two threads entering
the device. This will minimize the possibility of getting tape into the flow stream and
clogging the laminar flow elements.
• Face seal fittings do not need Teflon tape applied to the threads.
!
Warning: It is not recommended to use pipe dopes or sealants on the process connections
as these compounds can cause permanent damage to the controller should they get
into the flow stream.
Your flow controller can measure and control flow generated by positive pressure and/or
suction. Connect the controller so that the flow travels in the same direction as the flow
arrow, usually from left to right from the front of the device.
Operating Pressure
Maximum operating line pressure is 100 . If the line pressure is higher than 100 ,
use a pressure regulator upstream to reduce the pressure. Maximum proof pressure is
200 ; above this pressure the device may be permanently damaged.
▲
Caution: Exceeding the maximum specified line pressure may cause permanent damage
to the solid-state dierential pressure transducer.
Bleed Ports
Liquid flow controllers include bleed ports (8-32 Nylon tapped screw) on the front for the
removal of air bubbles.
✓
Note: A small amount of liquid will leak from the device during this procedure. Take
necessary precautions to prevent damage to anything nearby.
Bleed both of the ports as follows:
1. With the controller installed, and a >50% setpoint given, gently loosen the upstream
bleed port screw 1 to 2 turns, or until liquid begins to leak from the threads. Do not
remove the screw, as it has pressure behind it, is very small, is easy to lose, and is
delicate to rethread.
2. Gently tap the flow body to remove air bubbles (screwdriver handles work well). This
may not be visible or audible.
3. Gently tighten the screw until the leakage stops, taking care not to crush the nylon tip.
✓ Note: If your device is mounted in an inverted position, avoid using the bleed screws,
as liquid may leak and cause permanent damage.
A VCR®-compatible connection.
A VCO®-compatible connections.
5⁄64″ 8-32 Nylon-tipped
hex bleed screw
Loosen to bleed liquid,
but do not remove

8 Getting Started
Power and Signal Connections
Power can be supplied to your controller through either the power jack or the multi-pin connector on top of your device.
✓
Note: Power requirements vary based on analog configuration and valve type. Please reference the associated specification
sheet at alicat.com/specs for power requirements.
Standard 8-Pin Mini-DIN Pinout
Pin Function
Not connected Optional: 4–20 mA primary output signal
Static 5.12 Vdc by default. Optional: secondary analog output (4–20 mA, 0–5 Vdc, 1–5 Vdc, 0–10 Vdc) or basic alarm
Serial RS-232 RX / RS-485(−) input signal (receive)
Analog setpoint input
Serial RS-232 TX / RS-485(+) output signal (send)
0–5 Vdc Optional: 1–5 Vdc or 0–10 Vdc output signal
Power in (as described above)
Ground (common for power, digital communications, analog signals and alarms)
The above pinout is applicable to all devices with the Mini-DIN connector. The availability of dierent output signals
depends on the options ordered. Optional configurations are noted on the unit’s calibration sheet.
▲
Caution: Do not connect power to pins 1 through 6, as permanent damage can occur. It is common to mistake pin 2 (labeled
5.12 Vdc Output) as the standard 0–5 Vdc analog output signal. Pin 2 is normally a constant 5.12 Vdc.
For more pinout configurations, see diagrams starting on page 25.
Analog Signals
Primary Analog Output Signal
Most instruments include a primary analog output signal, which is linear over its entire range. For all analog output
configurations, the lowest output indicates zero flow, and highest indicates full-scale flow. Depending on the quality of
the grounding, a zero flow condition is approximately 0.010 Vdc.
For example, a 5 Vdc output from a 0–5 Vdc 100 CCM unit would indicate a flow of 100 CCM.
Option: Secondary Analog Output Signal
The default 8-pin Mini-DIN connector places the secondary analog output on pin 2 for both voltage and current signals.
Your device’s secondary analog signal may dier from its primary output signal.
The calibration sheet that shipped with the device shows which output signals were ordered.
Option: 4–20 mA Current Output Signal
If your controller has a 4–20 mA current primary or secondary output signal, your flow controller will require 15–30 Vdc
power.
▲
Caution: Do not connect 4–20 mA devices to “loop powered” systems, as this will damage portions of the circuitry beyond
repair and void the warranty. If you must interface with existing loop powered systems, always use a signal isolator and
a separate power supply.
Male Connector: Cable
Female Connector: Device
1
4
5
68
7
3
2 1
4
5
6
87
3
2

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Displaying Live Flow Data
Main Display
The main display has three primary functions:
• Displaying live temperature, pressure, and flow data
• Changing the flow or pressure control setpoint (page 12)
• Accessing the main menu (MENU) or the optional totalizer (NEXT) (page 10)
This screen displays live data for all flow parameters simultaneously. Live data is measured
1000 times per second and the LCD display is updated 10 times per second. The button
next to the four measurements highlight their values in the center.
Taring Your Flow Controller
MENU →TARE FLOW or TARES
Taring is an important practice that ensures your flow controller provides its most accurate
measurements. This function gives the flow controller a zero reference for flow measure-
ments. Gauge pressure can also be tared on all liquid devices.
How to Tare
When autotare is on (Autotare: On), flow rate is tared when a zero setpoint is given for more than two seconds (page 12).
Taring Flow
MENU →TARES →TARE FLOW
Flow tares should take place at the expected process pressure, with no flow. A message, “ENSURE NO FLOW BEFORE
PRESSING TARE” will be displayed. Press TARE to complete the taring process.
Taring Pressure
MENU →TARES →TARE PRESS
After pressing TARE PRESS, the message, “PRESS TARE WHEN VENTED TO AMBIENT WITH NO FLOW”, followed by “CURRENT PRESSURE
OFFSET:” will be displayed.
When to Tare
• Before every new flow measurement cycle
• After significant changes in temperature or pressure
• After dropping or bumping the flow controller
• After changing the device’s orientation
Option: Color TFT Display
Instruments ordered with a color display are functionally the same as standard backlit monochrome instruments. The
color enables additional on-screen information.
Multi-Color Display Indicators
• GREEN: Parameter labels and adjustments associated with the button directly above or below the label are green.
• WHITE: The color of each parameter will be displayed in white when the device is operating within device specifications.
• RED: The color of a parameter will be displayed in red when its value exceeds 128% of the device’s specifications.
• YELLOW: Menu items that are ready to be selected appear in yellow. This color replaces the > symbol in selections
on monochrome display.
✓ Note: Press the logo to turn o the color display backlight. The flow controller remains in operation while the backlight is o.
✓ Note: Color displays will require an additional 40 mA when using a 12 Vdc power supply. All other device specifications from
your device’s specification sheet remain in eect.
The main display. Note the button
behind the logo, which toggles the
device backlight.

10 Getting Started
Option: Collecting Totalized Flow Data
MAIN DISPLAY →NEXT (totalizer menu)
The optional flow totalizer displays the total amount of mass or volume that has flowed through the instrument since its
last reset, similar to a gasoline pump. It also enables batch dispensing (page 10).
• TOTAL/TIMER toggles between totalized flow and elapsed time as the highlighted parameter in the center.
• SETPT displays the current setpoint. Press to set a new setpoint, or to clear the setpoint (page 12).
• LPM (or another measurement of volumetric flow) displays the live flow rate. Press to change engineering units.
• (Optional) V AVG: Shows totalizer averaging, which displays average flow rate since last reset, updated live.
• BATCH selects the quantity to be dispensed in each batch. -NONE- appears if the batch mode is o.
• RESET clears all totalized data and immediately resets the timer to zero. The next batch, if set, begins immediately.
• MENU enters the main menu.
Totalizer Rollover Functions
The totalizer will report a maximum of 7 digits. By default, the placement of the decimal is the same as the live flow rate.
The totalizer can be configured at the time of order for the following behaviors:
• Rollover (Default): Totalizer resumes counting from zero as soon as the maximum count has been reached.
• Freeze: Totalizer stops counting at max count, until it is reset manually.
• Error (Default): Displays OVR status message when maximum count has been reached; compatible with the rollover
and freeze functions.
The elapsed time counter has a maximum value of 9999:59:59 (h:m:s) (416 days, 16 hours). If flow is still being totalized
at that point, the timer freezes, regardless of the behavior chosen above for the totalized flow readings.
Dispensing in Batches
Batch dispensing allows you to choose a desired total volume to flow, after which the valve closes. You can repeat batches
with a single button press. A totalizer is required to dispense batches.
Starting batch dispensing
1. From the totalizer screen, press BATCH. Choose the total quantity to be dispensed in each batch. Press SET to accept
the new batch size.
2. From the totalizer screen (page 10), press SETPT to choose a non-zero setpoint. Flow begins as soon as you
press SET.
✓ Note: Batch dispensing requires an active batch size and a non-zero setpoint. If your controller already has a non-zero
setpoint, flow begins as soon as you press SET from the batch size screen.
While a new batch is being dispensed, the BATCH button changes to show the quantity that remains to be dispensed.
When the batch size has been achieved, the BATCH button displays -DONE- and flow stops automatically.
The batch size can be changed while a batch is in progress. If the new batch size is larger than the current totalized flow,
then flow continues until the new value is reached. If the new batch size is smaller than the current totalized flow, then
the flow stops immediately. Press RESET to start the new batch.
Repeating a Batch
• For an identical, new batch, press RESET. Flow begins immediately.
• For a new batch of a dierent size, press BATCH, and select the new batch size. If there is a non-zero setpoint, flow will
begin as soon as SET is pressed.

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Pausing or Canceling a Batch
1. To stop flow while a batch is in progress, set the flow setpoint to zero by pressing SETPT → CLEAR → SET within the
totalizer menu. This will not stop the timer. Resume flow with a non-zero set point.
2. To remove a batch setting, press BATCH or REMAIN → CLEAR → SET. Deleting the batch does not aect the setpoint.
Flow will continue at the setpoint rate.
! Warning: Flow will resume immediately at the current setpoint when batch dispensing is turned o.
✓ Note: The batch size is retained across power cycles of your flow controller. It must be manually cleared when no longer
desired.
Using the Totalizer while Controlling Pressure
While using a liquid flow controller to control pressure, the flow rate may exceed the maximum measurable flow (128%
of full scale) with an abrupt pressure change. In this case, the totalizer will use the maximum 12% of full scale as the
measured flow rate, the totalized flow value will flash, and the TMF error will appear to indicate that the totalizer missed
flow data. Reset the totalizer to clear the error message.
Setting an upper flow limit (page 15) within the readable range will prevent this error; however, this will take preference
over reaching the pressure setpoint.
!
Warning: In certain situations, it is possible to exceed the batch size. As an example, if the feed pressure is too low to
achieve the flow setpoint and then pressure is suddenly increased, the batch size may be exceeded before the valve
reacts to the sudden burst of pressure.

12 Control
Control
Changing the Setpoint
SETPT or MENU →CONTROL → Setpt:
The setpoint selection screen indicates the engineering units and maximum allowable setpoint (e.g., LPM: +10.000 Max).
To cancel a setpoint, press CLEAR, then SET.
Adjusting Setpoint with an IPC
For controllers ordered with a potentiometer control knob (IPC), the setpoint source must be set to analog for the controller
to receive setpoint commands from the IPC (“Changing Between Setpoint Sources” below).
Leave the IPC knob at the midpoint when it is not in use.
Setpoint Setup
Using Autotare
CONTROL → Setpoint Setup → Zero Setpoint
When the setpoint is zero, the controller will automatically tare itself if autotare is enabled (default). This menu also
specifies how many seconds the controller will wait after given zero setpoint before taring, under Delay Before Tare.
Setpoint ramping (page 15) can either be set to honor the ramp rate limit or go to zero as quickly as possible.
Changing Between Setpoint Sources
CONTROL → Setpoint Setup → Setpoint Source
Liquid flow controllers with RS-232 or RS-485 communication will accept setpoints from the front panel and serial
commands (page 19), or from an analog signal.
• When the source is set to Serial/Front Panel , the controller will accept input from either the front panel, or an RS-232/
RS-485 connection. Neither source is a slave of the other, so the controller will accept the most recent command
from either source.
• When the source is set to Analog, the device ignores serial setpoint commands and will prevent setpoint input from
the front panel.
Setpoint with an Idle Modbus RTU Connection
CONTROL →Setpoint Setup → On Modbus Timeout
The device can be configured to set a zero setpoint after a certain amount of idle time on a Modbus connection. By
default, it will maintain the setpoint indefinitely. See page 17 for configuration details.
Managing Setpoint on Power Up
Power-Up Setpoint Value
CONTROL →Setpoint Setup →Power Up Setpoint →Value
By default, the controller remembers its last setpoint across power cycles. However, it can be changed to give a specified
setpoint upon power-up by selecting Fixed Setpoint and entering in the desired value. If the setpoint will be provided
digitally more often than every few minutes, a fixed setpoint on power-up is preferred to avoid wearing out non-volatile
memory in the device.
Power-Up Setpoint with Ramping
CONTROL →Setpoint Setup →Power Up Setpoint →Ramp
Any setpoint ramp will always start from zero on power-up. Similar to the zero setpoint option (page 15), the device
can either honor the ramp rate (Honor from 0) or jump to setpoint (Jump from 0) as quickly as possible.
Establishing Setpoint Limits
CONTROL →Setpoint Setup → Setpoint Limits
The setpoint limits menu configures upper and lower limits for selecting a flow or pressure control setpoint. By default,
the controller will only be limited by its measuring range; however, more strict limits may be beneficial in certain critical
applications.

2021.05.26  REV.   LIQUID FLOW CONTROLLER OPERATING MANUAL 13
Over a serial connection, requesting a setpoint outside the limit will be rejected and an error will be returned. When
using an analog setpoint signal, setpoints that are outside of the setpoint limits are treated as if they were at the nearest
limit. For example, if you request a setpoint that is below the lower limit, the controller sets the setpoint at the lower limit.
!
Warning: Flow controllers that have non-zero lower setpoint limits cannot be set to stop flow until the lower limit has been
cleared.
✓
Note: When changing from one control loop variable to another, the flow controller remembers setpoint limits as percentages
of full scale. For example, a 1-LPM limit on an LCR-2LPM controller (50% of full scale) will become a limit of 50  (50%
of 100 ) if the control loop is changed to gauge pressure.
Control Loop
Changing the Controlled Variable
CONTROL →Control Loop →Control
The controller can control the flow rate or the pressure in your process. Selectable control loop variables include volumetric
flow, gauge pressure, and valve drive.
✓ Note: When pressure is selected as the control loop variable, flow controllers with upstream valves will control the outlet
pressure. Those with downstream valves can control upstream backpressure, but these must be configured for this type
of control.
!
Warning: When changing the control loop from volumetric flow to gauge pressure, you may need to adjust the PID settings
for optimal stability and speed of response.
Adjusting the PD/PDF or PDI Control Algorithms
CONTROL →Control Loop →Loop Type
Your liquid flow controller uses an electronic closed loop controller to determine how to actuate its valve(s) in order to
achieve the commanded setpoint. These settings were tuned for your specific operating conditions, but changes to your
process sometimes require on-site adjustments to maintain optimal control performance. If you encounter issues with
control stability, oscillation or speed of response, fine-tuning your closed loop control may help.
For most applications, the PD/PDF algorithm is recommended.
Tuning the PD/PDF Control Algorithm
The controller’s default control algorithm (PD) employs pseudo-derivative feedback (PDF) control, which uses two editable
variables:
• The larger the Dgain, the slower the controller will correct errors between the commanded setpoint and the measured
process value. This is equivalent to the Pvariable in common PDF controllers.
• The larger the Pgain, the faster the controller will correct for osets based on the size of the errors and the amount
of time they have occurred. This is equivalent to the Ivariable in common PDF controllers.
✓
Note: The D and P variables in the PD/PDF control algorithm are more typically referred to as P and I, respectively, in
traditional PDF controllers.
Tuning the PDI Control Alogrithm
The controller’s PDI control algorithm (also called PDDI) is used to provide faster response, most commonly in dual-valve
flow and pressure controllers. This algorithm uses typical PI terms and adds a squared derivative term (D):
• The larger the Pgain, the more aggressively the controller will correct errors between the commanded setpoint and
the measured process value.
• The larger the Igain, the faster the controller will correct for osets based on the size of the errors and the amount
of time they have occurred.
• The larger the Dgain, the faster the controller will predict needed future corrections based on the current rate of
change in the system. This often results in slowing the system down to minimize overshoot and oscillations.

14 Control
Troubleshooting Valve Performance with PID Tuning
The following issues can often be resolved by adjusting the PID gain values for your liquid flow controller.
Fast oscillation around the setpoint
• PD: Reduce the Pgain in decrements of 10%.
• PDI: Increase the Pgain in increments of 10%, and then adjust the Igain to fine-tune.
Overshot setpoint
• PD: Reduce the Pgain in decrements of 10%.
• PDI: If Dis not , increase the Pgain in increments of 10%.
Delayed or unattained setpoint
• PD: Increase the Pgain in increments of 10%, and then decrease the Dgain by small amounts to fine-tune.
• PDI: Increase the Pgain in increments of 10%, and then increase the Igain to fine-tune.
✓ Note: Valve tuning can be complex. More detailed information is available at alicat.com/pid.
Limiting Flow while Controlling Pressure
CONTROL →Control Loop →Flow Limiter
Limiting the flow rate while controlling pressure can help to avoid exceeding the measurable range of the device as well
as prevent damage of sensitive devices later in the process. To limit flow:
1. Set the maximum value of flow rate desired by pressing MAX FLOW and entering the maximum value in the engineering
units displayed.
2. Set the Limiter Gain to 500 and adjust as needed. Limiter gain determines how aggressively the proportional
control function will correct the error when the flow rate exceeds the maximum flow setting. A higher value will
correct more aggressively, but is also more likely to oscillate near the flow limit.
✓
Note: If both flow limiting and pressure setpoint ramping are active when controlling pressure, the more restrictive function
will regulate the controller’s operation as it attempts to attain the setpoint.
Using a Control Deadband for Pressure Control
CONTROL →Control Loop →Control Deadband
The control deadband is designed for pressure control applications to improve stability. There is no active control within
the deadband setting.
To turn on the control deadband, enter a non-zero value in CONTROL → Control Deadband → Deadband. In order for the
deadband to activate, the setpoint must first be reached by the controller. If the process variable drifts to a deadband
limit, active control resumes until the setpoint is reached again.
The controller can be set to either hold the current valve position or close the valve(s) when in the deadband in CONTROL →
Control Loop → Control Deadband → When in Band. It is recommended to hold the current position on LC-Series devices.
Example: When making a step change from 15  to a setpoint of 30 , a deadband of ±0.25  allows absolute
pressure to vary between 29.75 and 30.25 . The device will increase pressure until it reaches the setpoint of 30 ,
then hold the current valve position until the pressure reading varies outside of the preset deadband.

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Setpoint Ramping
Setpoint ramping regulates how quickly the controller will reach the flow or pressure setpoint. It is often used to prevent
bursts of pressure or flow from damaging delicate instruments when starting a process.
To activate setpoint ramping, you will set a maximum ramp rate and configure when to enable the ramping function.
Setting the Ramp Rate
• Ramp is a quick way to change the maximum rate of change.
• Units is a quick way to change the engineering units used.
• Set By Delta / Time allows for more detailed control of the ramp rate including changing the value of the time period.
Ramping Options
Changing ramping options allows you to have a ramp in only one direction, increasing or decreasing. It also allows you
to ignore the ramp rate when initially powering on or commanding a zero setpoint.
• Ramp Up can toggle between on and o. When o, the ramp rate will not be honored when increasing flow to reach a
given setpoint.
• Ramp Down can toggle between on and o. When o, the ramp rate will not be honored when decreasing flow to reach
a given setpoint.
• Power Up toggles between Allow Ramp and No Ramp. If set to No Ramp, the device will ignore the ramp rate just after
powering on, otherwise it will honor the ramp rate.
• 0 Setpt determines whether the controller ramps when a zero setpoint has been given. If this setting is set to No
Ramp, when given a zero setpoint, the controller will immediately stop flow; otherwise it will ramp at the selected rate.
✓
Note: Setpoint ramping can be used with flow or pressure setpoints, depending on the control loop selected. Ramping for
pressure control limits how quickly pressure changes before reaching the setpoint. To limit flow rates directly while
controlling pressure, see page 14.
Displaying Valve Drive Percentage
The valve drive is represented as a percentage of the amount of voltage driven to the valve. Percentages do not directly
correlate with percentage open.
Viewing the valve drive percentage is particularly helpful for troubleshooting. A valve that has increased in percentage
over time indicates a likely clog in the system where more voltage is required to drive the valve to attain the same amount
of flow. A valve percentage of 0% indicates the valve is closed.
This information may be displayed on the main display as well as part of transmitted serial data. There are four valve
display options:
• None: No valve information is displayed.
• Main Screen: Only on the main display.
• Digital Data: Only in the serial data frame.
• Screen and Digital: Both the main display and serial data frame.

16 Device Information
Device Information
The ABOUT menu (MENU →ABOUT) contains useful information for setup, configuration, and troubleshooting.
Basic Device Information
ABOUT →About Device
This includes information on the following:
• MODEL: Device model
• SERIAL NO: Serial number
• DATE MFG: Manufacturing date
• DATE CAL: Most-recent calibration date
• CAL BY: Initials of the person who calibrated the device
• SW: Firmware version
• Display SW (color displays only): Firmware version of the display
Device Full Scale Ranges
ABOUT →Full Scale Ranges
This displays the maximum calibrated range of available flow and pressure readings. Most will include volumetric flow
and gauge pressure.
Manufacturer Information
ABOUT →About Manufacturer
About Manufacturer usually includes:
• Manufacturer name
• Web address
• Phone number
• Email address

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Setup
Sensor Setup
MENU →SETUP →Sensor
Choosing Engineering Units
SETUP →Sensor →Engineering Units
Changing device engineering units alters both the display and the data frame. Choose the parameter whose unit you
want to change, and then select your desired engineering unit, confirming the change on the last screen.
Flow and Pressure Averaging
SETUP →Sensor →Flow Averaging
SETUP →Sensor →Pressure Averaging
Averaging the flow over a longer time may be useful in smoothing fluctuating readings. This menu changes the time
constants of the geometric running averages for flow and pressure. Values roughly correspond to the time constant (in
milliseconds) of the averaged values. Higher numbers generate a greater smoothing eect, to a maximum of 255 ms.
Zero Band
SETUP →Sensor →Zero Band
The zero band threshold is an amount of flow under which flow values are displayed as . The maximum zero band is
6.38%. This function also applies to gauge pressure readings when using the optional barometer. For example, a 10-
controller with a zero band value of 0.25% would display all readings between -0.025 and 0.025  as  .
Configuring Serial Communications
MENU →SETUP →RS-232 Serial or RS-485 Serial
You can operate the flow controller remotely via its data connection for easy streaming and logging of all data. Before
connecting the flow controller to a computer, ensure that it is ready to communicate with your PC by checking the options
in this menu.
For more on how to issue commands from a computer, see page 19.
Unit ID
SETUP →RS-232 Serial or RS-485 Serial →Unit ID
The unit ID is the identifier that a computer uses to distinguish your device from other, similar devices when it is connected
to a network. Using the unit ID letters A–Z, you can connect up to 26 devices to a computer at the same time via a single
 port. This is called polling mode (page 19). Unit ID changes take eect when you select SET.
If you select “@” as the Unit ID, the flow controller will enter streaming mode when you exit the menu (page 20).
Modbus RTU Configuration
SETUP →RS-232 Serial or RS-485 Serial →Modbus Address
Modbus Address
The Modbus address is the identifier that a computer or programmable logic controller (PLC) uses to distinguish your
device from other devices when connected to a Modbus network. Values of 1–247 are available for use.
Modbus Idle Behavior
If a Modbus connection is idle for a specified amount of time, the device can be configured to set a zero setpoint. The
idle time will be infinite by default, and can be set in seconds up to 99999.9 (1 day, 3 hours, 46 minutes, 39.9 seconds).

18 Setup
Baud Rate
SETUP →RS-232 Serial or RS-485 Serial →Baud Rate
Baud rate is the speed at which digital devices transfer information. The flow controller has a default baud rate of 19200
baud (bits per second). If your computer or software uses a dierent baud rate, you must change the flow controller’s
baud rate in the BAUD menu to ensure they match. Alternatively, you can change your computer’s baud rate in Windows®
Device Manager. Baud rate changes take eect once you press SET, but you may need to restart the software for it to
recognize the change.
Display Setup
MENU →SETUP →Display
The options in the display setup menu adjust the contrast/brightness of the display and enable screen rotation.
Main Screen Options
SETUP →Display →MAIN Screen
• Any Key Press changes what happens when any of the parameter buttons on the main display (page 6) are
pressed (pressure or temperature, for example). By default, these buttons highlight their measurement in the center
of the display. If this option is set to Show Actions Menu, an option to change that parameter’s engineering units will
be shown, as well as an option to highlight the parameter.
• Show Valve Drive shows or hides the valve’s drive percentage. See page 15.
Screen Lighting
SETUP →Display →Screen Lighting
The options and wording in the screen lighting menu will vary for monochrome versus color displays.
• On monochrome displays, press LESS CONTRAST or MORE CONTRAST to adjust the contrast levels and move the contrast
indicator left or right. POWER UP Lit or Dark toggles whether the backlight of the unit will be on when the device
powers on.
• On color displays, press DIMMER or BRIGHTER to adjust the brightness level and move the brightness indicator left
or right.
Display Rotation
SETUP →Display →Display Rotation
The device has the option of inverting (flipping) the screen upside-down, as configured in this menu.
Advanced Setup
MENU →SETUP →Advanced
The advanced setup menu contains settings and detailed information that are useful when troubleshooting with
customer support.
Factory Restore
SETUP →Advanced →Factory Restore
This will immediately take you to a confirmation screen. When troubleshooting, an applications engineer may recommend
doing a Factory Restore. If something is not acting as expected, please contact an applications engineer prior to doing
a Factory Restore.
Register Status
SETUP →Advanced →Register Status
The Register Status screen displays live values for the internal device registers. Many of these values can help an
applications engineer diagnose operational issues over the phone. Some register values clearly distinguish between
hardware and operational problems, which speeds up the troubleshooting process.
Edit Register and Device Properties
SETUP →Advanced →Edit Register
SETUP →Advanced →Device Properties
! Warning: Editing these settings may cause the device to become inoperable. Do not modify them without working with
customer support.

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Serial Communication
Connecting your device to a computer allows you to log the data that it generates. The device communicates digitally
through its communications connector and cable using a real or virtual  port on your computer. This section of the
manual shows you how to operate the flow controller using  commands.
Establish Communication
After connecting your device using a communications cable, you will need to establish serial communications through
a real or virtual  port on your computer or programmable logic controller (PLC).
• If you have connected your deviceto a serial port, note its  port number, which can be found in the Windows®
Device Manager program.
• If you have used a  cable to connect your device to your computer, then in most cases it will recognize your 
as a virtual  port. If it does not, download the appropriate device driver at alicat.com/drivers and note the
 port number as found inWindows® Device Manager.
The controller will be configured with the following settings:
• Baud: 19200 (by default; others can be used if the computer, computer software, and the controller are all set to the
same rate)
• Data bits: 8
• Parity: none
• Stop bits: 1
• Flow control: none
Alicat’s Serial Terminal Application
Alicat’s Serial Terminal is a preconfigured program for serial communications that functions much like the older Windows®
HyperTerminal, with plain text in a command-line format.
Download Serial Terminal for free at alicat.com/drivers. Once downloaded, simply run SerialTerminal.exe. Enter the 
port number to which your device is connected and the baud rate of the flow controller. The default baud rate is 19200,
but this is adjustable by entering the RS-232 Serial menu on your flow controller (page 17).
Modbus RTU Communication
For details on Modbus commands, please visit alicat.com/manuals for the Modbus operating bulletin.
Serial Streaming vs. Polling
✓
Note: In what follows, 88indicates an ASCII carriage return (decimal 13, hexadecimal D). For many devices, this is the same
as pressing the Enter key. Serial commands are not case-sensitive.
Polling Mode
Your device was shipped in polling mode with a unit ID of A, unless requested otherwise. Polling the device returns a
single line of data each time you request it. To poll your device, simply enter its unit ID.
Poll the device: [unit ID]88
Example: a88(polls unit A)
You can change the unit ID of a polling device by typing:
Change the unit ID: [current unit ID]@=[desired unit ID]88
Example: a@=b88(changes unit A to unit B)
You can also do this via the device’s front panel menu (page 6). Valid unit IDs are letters A–Z, and up to 26 devices
may be connected at any one time, as long as each unit ID is unique.

20 Serial Communication
Streaming Mode
In streaming mode, your device automatically sends a line of live data at regular intervals. Only one unit on a given 
port may be in streaming mode at a time. To put your device into streaming mode, type:
Begin streaming: [u nit ID]@=@88
Example: a@=@88(puts device A into streaming mode)
This is equivalent to changing the unit ID to “@”. To take the flow controller out of streaming mode, assign it a unit ID by
typing:
Stop streaming: @@=[desired unit ID]88
Example: @@=a88(stops and assigns unit ID of A)
When sending a command to a device in streaming mode, the flow of data will not stop while the user is typing. This may
make the commands you type unreadable. If the device does not receive a valid command, it will ignore it. If in doubt,
simply hit 88and start again.
The default streaming interval is 50 ms, but this can be increased by changing Register 91 while the device is in polling
mode:
Set streaming interval: [unit ID] w91=[number of ms]88
Example: aw91=50088(streams new data every 500 ms)
Taring
Before collecting flow data, be sure to tare your controller. If auto-tare is enabled, this can be accomplished by providing
a setpoint of 0 for at least 2 seconds.
Manual taring can be accomplished through two separate commands for flow and pressure. Taring flow sets the zero
flow reading and must be done when no flow is passing through the flow controller:
Tare flow: [unit ID]v88
Example: av88(sets flow reading to zero)
Taring pressure sets the zero pressure reading and must be done when the device open to ambient pressure:
Tare gauge pressure: [unit ID]p88
Example: ap88
Collecting Flow Data
Collect live flow data by typing the [unit ID] 88command or by setting your flow controller to streaming. Each line of
data for live flow measurements appears in the format below, but the unit ID is not present in streaming mode.
A 14.70 +24.57 +02.004 +02.004
ID Gauge Pressure Temperature Volumetric Flow Setpoint
Single spaces separate each parameter, and each value is displayed in the chosen device engineering units (page 17).
You can query the engineering units of the serial data frame by typing:
Query live data info: [unit ID]??d*88
Example: a??d*88(returns the data frame descriptions)
Additional columns, including status codes (page 6), may be present after the last number. The unit ID appears in
the data frame only when the flow controller is in polling mode.
Before attempting to send a setpoint to your controller serially, confirm that its setpoint source is set to Serial/Front
Panel (page 12).
There are two ways to command a new setpoint over a serial connection, as described below. In either of these methods,
the data frame returns the new setpoint value when it has been accepted as a valid setpoint.
This is how to send the desired setpoint value as a floating point number in the engineering units selected:
New setpoint: [unit ID]s[floating point number setpoint]88
Example: as5.4 488(setpoint of +5.44 LPM)
In this method, your controller’s full scale range (FS) is represented by a value of 64000, and a zero setpoint is represented