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937A Multi-Sensor System
Set Points
Control your system with five independently adjustable relay set points. They
may be set or disabled from either the front panel or the optional
communications module. The set points are nonvolatile, remaining unchanged
after powering down or during a power failure.
The Controller also includes additional protection and control set points to turn
a cold cathode sensor off at higher pressures, extending the operating time
before maintenance is required.
Leak Test
The
Leak Test mode consists of a bar graph and variable rate beeper to
locate system leaks. This mode operates with any sensor except a
capacitance manometer.
Analog Output Signals
Analog output signals, which can be sent to a data acquisition system, are
available for each sensor from the Analog connector on the Analog Module.
These include buffered, logarithmic, and combination logarithmic output.
Buffered and logarithmic analog outputs are available simultaneously from all
sensors.
A buffered analog signal responds immediately to sensor signal changes.
Logarithmic pressure output ranges from 0 to 10 V and is scaled to 0.6 V per
decade of pressure change, regardless of sensor type or channel. However,
these outputs are updated each 50 to 250 ms depending on the number of
sensors in the controller.
Combination logarithmic output is a combined reading of pressures from a
cold cathode sensor and its control sensor (a Pirani or other medium pressure
sensor). It provides a continuous analog output representing a wide range of
pressure, from 1.0 x 10
-11
to as high as 1000 Torr, from a single output.
Computer Interface
Direct computer communication is available to control front panel functions or
read pressure and other information remotely. A Controller slot for an optional
module supports RS-232 and RS-485.