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937A Multi-Sensor System
Five set point relays are available – one for slot CC and two each for slots
A
and
B. If a single-channel module is used in Slot A or B, both relays are
controlled by that channel and may be independently adjusted to different set
point pressures.
When using more than one sensor type, verify
that the correct sensor and cable are connected
to each module.
The figure to the right shows possible module
arrangements.
Cold Cathode
A cold cathode sensor module can be installed
in any Slot –
CC, A, or B. The cold cathode
sensor module is a single-channel module.
Slot
CC will operate only with a cold cathode sensor module installed. If any
other sensor module or no sensor module is installed in Slot CC, the Series
937A Controller will simply ignore it.
A Cold Cathode Sensor Module must be plugged into Slot
CC if capacitance
manometer auto-zero is to be used (see Capacitance Manometer Auto-Zero
Feature, page 55).
Three DIP switches on the Analog Module are set to control the operation of
the cold cathode sensor (see Analog Module, page 31).
Setting two jumpers on the cold cathode sensor module can make it
compatible with either the Series 937A Controller or older Series 937 or Series
929 controllers. For use in the Series 937A Controller,
1
Set the
uP/Com (microprocessor/communications module) jumper to uP.
2
Set the
SW/PS (software/direct power supply) jumper to SW.
An older cold cathode sensor module, ( rear enable connector labeled
H.V.
Enable) has either only the first of these jumpers or neither. To use older
modules in a Series 937A Controller or new modules in a Series 937 or 929
controller, contact HPS™ Products Applications Engineering at MKS Vacuum
Products Group to request the application note on
Configuration of Cold
Cathode Modules for 929/A/937/A Controllers.
Pirani
A Pirani sensor module can be installed in Slots
A, B, or both. Either a single-
channel or a dual-channel module is available.
The Pirani module has no switches or jumpers to set.
Though the Pirani and Convection Pirani sensor modules are designed to
prevent damage to themselves or their sensors if sensors were accidentally
interchanged, an inaccurate pressure would be indicated if they were.
Sensor module
options for slots A
and B