Brooks On-Board 8, Инструкция по установке и обслуживанию

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Cryo-Torr 8600 Compressor Operation, Installation and Maintenance Guide
©2013 Brooks Automation Inc. Pub. No. 8040564, Rev. AA, 01/15/13 ECO No. 64541 3-1
Section 3 - Troubleshooting
Introduction
The primary indication of trouble in a vacuum pumping system is a rise in
base pressure of your vacuum chamber. A rise in the base pressure may be
caused by a leak in the vacuum system, a fault in the On-Board GLE
Cryopump, or by saturation of the 15K cryo-adsorbing charcoal array
within the On-Board GLE Cryopump (regeneration may be necessary). If
the On-Board GLE Cryopump temperature is below 20K it should pump at
rated capacity; a high base pressure is usually caused by an air-to-vacuum
leak in the system.
If you suspect a leak in your vacuum system, isolate the On-Board GLE
Cryopump by closing the Hi-Vac valve and leak check your vacuum
chamber. If no leaks are found, a leak may be present below the Hi-Vac
valve (cryopump). Leak checking below the Hi-Vac valve should be
performed with the On-Board GLE Cryopump shut off and at room
temperature. Leak checking while the On-Board GLE Cryopump is
operating may mask leaks that are present (due to the ability of the
cryopump to pump helium). If no leak is found, refer to the cryopump
troubleshooting procedures summarized in
Table 3-1 .
The problems presented in Table 3-1 are followed by possible causes and
corrective actions. The causes and corresponding actions are listed in their
order of probability of occurrence.
Maintaining a log of certain parameters during normal operation can be a
valuable tool in troubleshooting the cryopump. The log may contain many
parameters, however, the following minimum parameters should be
included: the cooldown time to 20K, the roughing time to 50
μ
, the time to
base pressure at crossover, the time between regeneration cycles, and the
compressor pressure reading.
Technical Inquiries
Please refer to Appendix A of this manual for a complete list of the CTI-
CRYOGENICS world wide customer support centers.