© Edwards Limited 2012. All rights reserved.
Page 41
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Operation
M561-00-880 Issue C
4.3
Manual shut-down
CAUTION
If you stop the pump without the nitrogen purge cycle, for example by using the EMS button, on processes that
have condensable or solid by-products then the pump may not restart.
The pump can be shut down using either the MicroTIM, the PDT or the front panel controls. Note that only the item
in control can stop the pump (refer to
Section 1.4
).
Note:
The EMS button will always stop the pump. It does not matter which item has control. Refer to
Section 4.6
.
If the pump is not going to be required for some time, switch off the electrical supply and the cooling-water supply.
4.3.1
Shut-down modes
Auto shut-down
introduces a nitrogen purge cycle which lasts for 15 minutes before the pump is shut down. This is
the recommended shut-down mode.
Fast shut-down
immediately stops the pump without gas purge.
Ramped shut-down
is an optional mode for iXH. In some harsh applications, process residues can accumulate in the
pump mechanism during shut-down, making it difficult to restart the pump next time. To prevent this problem a
special ramped shut-down can be performed. Contact Edwards for more information.
4.3.2
MicroTIM operation
Use your control equipment to reset the pump start/stop signal to the interface connector. The Running LEDs will
then go off, and the pump running status output signal will open.
4.3.3
PDT operation
Press the stop button on the PDT (refer to Appendix A1 for more information). You can choose whether to select
Auto or Fast shut-down mode.
4.3.4
Front panel control operation
Press and hold the stop button (
Figure 2
, item 4) for 5 seconds to stop the pump in Auto shut-down mode
(recommended, refer to
Section 4.3.1
above). Repeat within 10 seconds to stop the pump in Fast shut down-mode.
The running LED (
Figure 2
, item 2) flashes whilst the pump is slowing down and will then turn off when the pump has
shut down.
WARNING
If you shut the system down and don’t isolate it from the electrical supply, do not disconnect the
Pump Display Terminal or release control from the Pump Display Terminal or front panel. If you do
the system could be started by another Module.
WARNING
Do not remove the inlet connections until the pump has been allowed to stop rotating and the
power has been isolated. The pump can take up to three minutes to completely stop.
