Models 947, 948 and 960 Leak Detectors Operations and Service Manual
4-25
4.2.7.2 Replacement of the TC2 Gauge in the Service Block Assembly
WARNING
Liquid nitrogen causes burns upon contact. Use appropriate
protective devices, including heavy loose gloves and eye or
face shields.
NOTE
Models 948/960 only:
Before servicing the Spectrometer Tube,
refer to “Liquid Nitrogen Cold Trap (Models 948/960 only)” on
page 4-10 for the procedure to clean the Cold Trap. Do not
refill the Cold Trap until service is complete.
Figure 4-11 shows the valve block removed from the system. To replace the TC2 gauge in
the Service Block Assembly (SBA):
1. Press the VENT button on the front panel to vent the leak detector.
2. Disconnect the mains power supply and make sure all pumps are off.
3.
Models 948/960 only:
Empty the LN
2
Cold Trap. Refer to the warnings listed above.
NOTE
It is not necessary to remove the valve block to replace the
TC2 thermocouple gauge.
Figure 4-11
TC2 Gauge in the SBA
4. Loosen and remove the KF25 clamp
➀
to remove the thermocouple gauge
➁
,
adapter
➂
, centering ring and O-ring.
5. Remove the thermocouple gauge from the adapter.
6. Remove the O-ring from the centering ring.
➀
➁
➂
Summary of Contents for 948
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