Ulvac GI-M2, Инструкция по эксплуатации

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12.1. Causes of No Emission Current and Corrective Actions
The table below gives the causes of no stabilized emission current and corrective actions.
Possible cause Corrective action
Pressure is high Check pumping system.
Filament burnout Replace sensor head.
Filament wear Replace sensor head.
Contamination in sensor head Replace sensor head.
Poor contact or burnout of sensor head
cable
Re-connect or replace cable.
Failure of power supply circuit in controller Repair controller.
Basic conditions under which emission current flows include the following five.
1. Pressure within a measurement range
2. Required bias voltage is applied between the filament and grid.
3. Filament temperature is at the required level.
4. Filament has a required surface area.
5. Grid has a required clean surface area.
Emission current will not flow if any of these conditions is not met.