1.3
Description
The Q Series 3 Exhaust Pressure Module is intended for use with a BOC Edwards QDP Drystar
Pump fitted with a QDP Gas Module. The Q Series 3 Exhaust Pressure Module provides the
following nitrogen supplies to the QDP pump :
•
Exhaust-purge
•
Inlet-purge.
Nitrogen gas is routed to the pump through
1
/
4
inch pipelines. A schematic diagram of the
Q Series 3 Exhaust Pressure Module is given in Figure 1.
The nitrogen supply for the inlet-purge is connected to the front of the Exhaust Pressure Module.
The nitrogen supply passes through a solenoid-valve inside the Module and is then connected to
the QDP pump. The inlet-purge can be switched on and off by this valve which is controlled by
your control equipment.
The nitrogen supply for the exhaust-purge comes from the auxiliary nitrogen outlet on the QDP
Gas Module. This auxiliary nitrogen outlet is connected to the exhaust-purge nitrogen inlet on
the Exhaust Pressure Module.
The pressure in this pipeline is monitored by two
pressure-switches (with gold contacts) in the Exhaust Pressure Module. One pressure-switch
gives a pressure warning signal and the other pressure-switch gives an over-pressure signal.
These signals are used to control the electrical supply and the nitrogen supply to the QDP pump.
The 17-way connector at the end of the electrical cable (which is on the back of the Exhaust
Pressure Module) is connected to the auxiliary connector on the QDP Gas Module. The electrical
supply for the inlet-purge solenoid-valve comes through this cable. This cable also carries the
signals from the pressure-switches, which pass back through the Gas Module and are available
on the 19-way connector on the Gas Module.
2
Q Series 3 Exhaust Pressure Module