PRESSURE CONTROLLER operating manual
11
Remote-Sensing Controller
PC3-Series models sense and
control the pressure at some point
in the system outside the pressure
controller itself. All PC-Series control-
lers can be ordered with an addi-
tional NPT port on the front, which
is connected directly to the pressure
sensor in the device. The pressure
sensor is isolated from the flow path
in this configuration.
Using Alicat Pressure Instruments with Fluids
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 20 SLPM of air will
be limited to roughly 0.5 LPM 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
, or
contact us (
) 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.
A 100 PSI gauge pressure controller with
a remote sensor port (in front), and an
8-pin mini-DIN serial data connection.
Gas
Supply
Alicat PC3
Controller
Flow
Pressure Sensor Line
(no flow)
Pressure-Controlled
Process
Process