Atmospheric Calibration - Agilent Technologies 947 Betriebs- Und Servicehandbuch

Models 947, 948 and 960 Leak Detectors Operations and Service Manual

4.2.8.4.2 Atmospheric Calibration

Calibration of the system pressure thermocouple (TC2) gauge to atmosphere is only required
if the system TC2 gauge is replaced or if the calibration appears to be off.
To calibrate the system pressure thermocouple (TC2) gauge to atmosphere:
1. Once the system thermocouple (TC2) has been replaced and before powering up the
leak detector, turn off the ROUGH pump and DETECTOR switches.
2. Turn on the power switch located on the rear panel of the 947/948/960.
3. Wait for the system NOT READY LED to illuminate.
4. Open the turbo vent screw located on the side of the turbo pump housing.
5. On the Service Pendant, press shift and the SY TC ATM key.
The Pendant screen confirms that the calibration was successful by displaying the
OK prompt.
The Pendant screen displays FAILED before the OK prompt, indicating that the
calibration was not successful. This could be the result of a defective or
contaminated thermocouple gauge, or that the actual pressure was not at or near
atmosphere.
If the calibration was not successful, contact Varian Vacuum Technologies Customer
Service at 1-800-8VARIAN.
6. If the calibration was successful:
Close the turbo vent screw.
Replace any panels that were previously removed.
Calibration of the TC2 gauge is complete. You can now proceed with testing or place the
system in the mode you desire.
Do not replace the side panels before performing this
NOTE
procedure. You need access to the turbo pump.
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