Pfeiffer ASM 340 - Inlet Vent, Memo Function, and Zero Activation

Advanced settings
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7.4.6 Inlet vent
This function allows an inlet vent after a hard vacuum test stop. It allows the detector's
inlet, and therefore the connected part or installation, to return to atmospheric pressure.
This function is secure: a confirmation message "Inlet vent? Please confirm." appears
each time the operator requests an inlet vent.
Fig. 24: "Activate VENT" screen using a function key
If ’Automatic’ is selected, inlet vent enters automatically when is pressed to stop
the test.
If 'Operator' is selected, press the corresponding function key to return the detector to
atmospheric pressure.
Inlet vent manual activation from:
● the [Inlet vent] function key
● the "Standard" screen (see 6.1.4) ref. 6.
7.4.7 Memo function
This function freezes the "Standard" screen and displays the most recent test result: the
leak rate displayed flashes.
From the "Settings" screen, press [Test] [Inlet vent].
Inlet vent  Activate the function.
Function activated if ’automatic’ is set.
Delay Setting required if ’automatic’ is set.
 Set the delay.
Delay = time between the test stop and the automatic opening of the inlet vent valve.
Allows a controlled valve to be closed before inlet vent.
Vent Timer Setting optional if "automatic’ is set.
 Activate the closing of the inlet vent valve.
 Set the duration.
Duration = time between the opening of the air inlet valve and its automatic closing.
The automatic closing after a set duration is used to limit consumption of dry air or ni-
trogen, if purge is connected.
For quick access from the control panel, set a function key for [Inlet Vent] (see
7.7.2).
To lock the control for the inlet vent valve, delete the [Inlet vent] function key. The
icon will stay on the "Standard" screen as an indicator but manual activation by
the operator will be deactivated.
NOTICE
Automatic inlet vent
Never programme ’automatic’ inlet vent while the detector is connected to a high vacu-
um chamber or semi-conductor process chamber!
Select 'Operator' and/or delete the function key allocated to the automatic inlet vent. The
inlet vent must be carried out using the menu, which can be password locked.
By connecting an inlet vent (or nitrogen) line to the inlet vent, the detector's tracer
gas pollution is reduced.
From the "Settings" screen, press [Test] [Memo Function].
Active  Activate the function.