Alicat P Series Pressure Gauge - Manual (Page 81)

81
NOTES FOR USING PC-EXTSEN DEVICES
PC-EXTSEN units connect a Pressure Controller (with no internal pressure
sensor) to an end-user supplied external pressure sensor. Designed mainly
for the vacuum coating industry, the PC-EXTSEN marries the sensing ability
of an existing capacitance manometer or ion gauge with a Alicat’s 16 Series
electronics package and internal PID algorithm. This enables fast and precise
control of extreme vacuum conditions in the coating chamber.
The PC-EXTSEN receives a linear analog signal from the external sensor. This analog
signal corresponds to a full scale range that is specified by the user at the time
of order (and corresponds to the scale of the external sensor). The PC-EXTSEN
interprets this analog signal as its sensed pressure.
The PC-EXTSEN then utilizes its proportional control valve to control the flow
of gas into the chamber, allowing for closed loop vacuum control based on the
interpreted signal. Set-point control and PID tuning all happen through the
instrument’s interface, via the buttons on the display, or a user selected analog
interface (0-5V, 0-10V, or 4-20mA), or through a multidrop RS-232 interface.
There are two base models of PC-EXTSEN controllers, the PC-EXTSEN-D, and the
PC-EXTSEN-D-ISC.
The PC-EXTSEN-D has an 8 pin Mini-DIN female electrical connector as its electrical
connection to power, ground, signal input from the external sensor, RS-232 transmit
and receive, as well as analog transmit and receive. The PC-EXTSEN-D also has a
barrel plug electrical connection if you choose to power the device through a wall
mounted AC adaptor, rather then wiring power to the 8 pin minidin connection.
The PC-EXTSEN-D-ISC is identical to the PC-EXTSEN-D except it has an additional
locking 6 pin industrial electrical connector which is intended for use as a dedicated
connection to your external sensor, leaving the 8 pin Mini-DIN connection available
to be used as a dedicated RS-232 or analog interface connection.
Please refer to the appropriate sections of this operating manual for complete
information regarding use and tuning of your PC-EXTSEN controller.
When using a PC-EXTSEN-D-ISC device, it is recommended that power
and communications to the PC-EXTSEN-D-ISC device be wired through
the 8 pin Mini-DIN connector and that the industrial connector is
maintained as a dedicated connection to the external sensor.
WHEN USING THE INDUSTRIAL CONNECTOR AS A DEDICATED
CONNECTION TO THE SENSOR, DO NOT WIRE ANY SIGNAL INPUT INTO
PIN 2 ON THE Mini-DIN CONNECTOR.