Edwards ELD500 Series

D135-10-880C - Operation
Page 77
Contamination protection
Main menu > Settings > Surveillance > Contamination Protection
If enabled, this mode will cause the ELD500 to close all inlet valves as soon as the measured
leak rate exceeds the programmed limit. Once the START key is pressed, the value must drop
below the limit once as the function will otherwise be triggered when the alarm delay time
has elapsed. This will prevent an excess amount of helium from entering the mass
spectrometer. Consequently, the leak detection unit is prevented from becoming
contaminated by helium. The helium entering the specimen can be pumped out using an
external pump. If no pump is available, the recommendation is to ventilate the specimen
before continuing with the measurements.
Pressure limits for vacuum mode.
Main menu > Settings > Monitoring functions > Pressure limits for vacuum mode
With this function the default settings for the pressure limits EVAC - GROSS and FINE can be
changed.
This might be necessary if other gases than air will be pumped by the ELD500. The pressure
signal from the gas dependent inlet pressure (P1) will dump false signals. With changing the
pressure limits this performance will be adjusted.
Softkey No. 1: Back
Softkey No. 3: Off
Softkey No. 4 Enter limit value
Selection between air or Argon
Softkey No. 5: ?
Help text
Softkey No. 6: On
Softkey No. 7: Off
Softkey No. 2: 
Decrease change over threshold EVAC-GROSS
Selectable between15-3 mbar (Default value 15 mbar)
Softkey No. 3: 
Decrease change over threshold GROSS-FINE
Selectable between 0.2 to 0.05 mbar (Default value 0.2 mbar). For the ELD500 DRY and the
ELD500 FLEX the changeover is between 0.1-0.05 mbar (Default value 0.2 mbar).
Softkey No. 4 Adjustment for ARGON
Selection between air or Argon