Pfeiffer Vacuum A 1204H, Operating Instructions Manual

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34
Operation
6.4 Use with two HHRs
Two HHR can be connected to the pump ( HHR on pump front panel, J8 at the rear panel
(see 4.2) ). Reading of data and parameters can be done on both HHR, even if they do
not control the pump. Only one HHR can control the pump.
To take the control with a HHR, press the CONT. key: then, the text HHR flashes on
the right corner of the display. The control of the pump is now not possible from an-
other HHR.
To give the control back, press on the
CONT. key.
6.5 Operation monitoring
When a problem occurs, the user is informed through:
– the relevant fault indicator light: yellow lit in case of warning, red lit in case of alarm,
– the audible buzzer warning (if preselected),
– the fault contacts on J1 remote connector are activated,
– display of fault message on the HHR,
– a message via the RS-232 or RS-485 serial link.
Messages are listed in the Malfunctions chapter (see 11.3) .
NOTICE
Overpressure in the exhaust line
The pump is equipped with an exhaust pressure monitoring sensor that monitors the
pressure at the fonctionnal block exhaust, but not in the exhaust line. It is the responsi-
bility of the user to:
Prevent the risks related to excess overpressure in the pumping installation.