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DLD4040 R2.55 & R3.54 Manual | Surface Concept GmbH
• Check the detector output by means of the rate meter of your end-user software (e.g. GUI software).
The dark count rate without any source should be as given in the specification sheet.
• Now you may start carefully with an electron source observing the detector output.
Keep in mind the description about the important operation details in
.
Note
Figure 5: Schematic sketch on voltage ramping with external reference voltage.
• Increase the external reference voltage until reaching the desired voltage for “MCP-F”.
• A schematic sketch on how to ramp the voltages is given in
• Watch the vacuum pressure while increasing the high voltage; turn the voltages back, if an unusual
increase is observed in the pressure (indicator for high voltage sparking).
High voltage sparks may seriously damage the detector anode/meander or the MCPs.
Observe the chamber pressure carefully every time the high voltage is turned on. Switch
off the high voltage immediately in case of a temporary pressure rise by an order of
magnitude or more. This indicates high voltage sparking.
If sparking occurs, turn down the high voltage immediately and wait some time (up to 5
min.). Start the “Start-Up” procedure again with an increased ramp time. Turn off the high
voltage completely, stop the procedure and call your provider for further assistance, if is
it not possible to reach the operation voltage without sparking.
