Varian 948, Operation And Service Manual

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Models 947, 948 and 960 Leak Detectors Operations and Service Manual
4-30
9. Type XYZZY<CR>, then 100 INIT-TPTCZERO<CR>.
❑ The system should respond OK .
❑ The test port pressure on the test port pressure bar graph should read 1.0E-01 Torr.
A FAILED response on the PC is an indication that the calibration was not successful.
This could be the result of a defective or contaminated thermocouple gauge. If
necessary, replace the thermocouple gauge.
If after replacing the thermocouple gauge, calibration is still not successful, contact
Varian Vacuum Technologies Customer Service at 1-800-8VARIAN.
10. If the calibration was successful:
❑ Press the VENT button and remove the T-manifold, tuning leak, and reference TC
from the test port.
❑ Place test port plug into the test port and tighten the test port tightening nut fully.
❑ Remove the PC and connect the Service Pendant.
❑ Perform the next part of the calibration procedure (“Atmospheric Calibration”).
4.2.7.7 Atmospheric Calibration
To perform atmospheric calibration:
1. If the system is not already in VENT mode, press the VENT button and verify that the
VENT LED is illuminated.
2. Wait approximately ten seconds for the test port pressure to stabilize.
3. On the Service Pendant, press the TP 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.
❑ Successful, calibration of the TC1 gauge is complete. You can now proceed with test-
ing or place the system in the mode you desire.