6.7 Operation monitoring
6.7.1 Operating mode display via LED
The LEDs on the front panel of the DCU display basic operating statuses.
LED
Symbol LED status
Display
Meaning
Green
Off
without current
On, flashing
"Pumping station OFF", rotation speed ≤ 60
rpm
On, inverse flashing
"Pumping station ON", set rotation speed not
reached
On, constant
"Pumping station ON", set rotation speed
reached
On, flashing
"Pumping station OFF", rotation speed > 60
rpm
Red
Off
no error, no warning
On, flashing
Warning
On, constant
Error
Tbl. 12:
LED display and meaning at the DCU
6.7.2 Temperature monitoring
If threshold values are exceeded, output signals from temperature sensors allow the vacuum pumps to
be brought to a safe condition. Depending on pump type, temperature threshold values for warnings
and malfunction messages are saved unchanged in the electronic drive unit. For information purposes,
various status queries are prepared in the parameter set.
● The drive power of the turbopump is reduced in case of impermissible motor temperature or non-
permissibly high housing temperature. This can cause the motor to fall below the set rotation
speed switchpoint and so result in switching off of the turbopump.
● At a non-permissibly high temperature (> 75 °C) of the backing pump, the motor rotation speed is
reduced to nominal rotation speed to prevent overheating. After cooling down (< 72° C) the back-
ing pump runs at set rotation speed again.
6.8 Operation with fore-vacuum valve
The fore-vacuum safety valve is located in the fore-vacuum line between the turbopump and the back-
ing pump. It protects the process vacuum and the turbopump against inadvertent venting after switching
off the backing pump or in case of power failure. The fore-vacuum valve switches to the other pumping
station components after a time delay to avoid backflows when switching on. The valve is closed cur-
rentless.
●
[P:010]
pumping station "On" = fore-vacuum safety valve opens after 8 seconds.
●
[P:010]
pumping station "Off" = fore-vacuum safety valve is closed.
6.9 Switching off and venting
We recommend
Vent the turbopump after shutdown. By doing so, you prevent particles flowing back into
the vacuum system from the fore-vacuum area.
6.9.1 Shutting down the turbo pumping station
Procedure
►
Shut down the turbo pumping station.
– The components shut down according to their configuration. The pumping station remains
ready for operation.
► Shut off the entire current supply at the master switch.
Operation
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