Models 947, 948 and 960 Leak Detectors Operations and Service Manual
4-7
4.2 Yearly Maintenance
4.2.1 Replacing the Calibrated Leak
4.2.2 Re-calibrate the Internal Calibrated Leak
Helium calibrated leaks typically degrade at 3 percent per year. The calibrated leak
supplied with your 947/948/960 must be checked at least once a year to ensure it is at the
value stated on its label. Failure to check the leak could result in unreliable testing. You can
arrange for testing and re-calibration at a lab of your choice.
Varian Vacuum Technologies provides NIST-traceable calibrated leak testing and
verification services. Contact Customer Service at 1 (800) 8VARIAN to arrange for
re-calibration.
4.2.2.1 Removing the Internal Calibrated Leak
The calibrated leak is located in the main cabinet area near the top of the leak detector as
shown in Figure 4-1.
Figure 4-1
Location of the Calibrated Leak
Thumb Screw
Rear of Leak Detector
Summary of Contents for 948
Page 175: ......
