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System Start-up and Shutdown
Diffusion Pump Startup
NOTE: The Diffusion Pump System Startup sequence takes at least 30 minutes.
First, the Peltier Baffle cooler is turned on while the pump heater is left off. This
step lasts 15 minutes and allows the cooler to drop in temperature before any
pump vapors are created. When the foreline pressure reaches proper vacuum
(~500 mTorr), the pump heater is turned on. When the heater has reached
temperature, approximately 15 minutes, the ion trap electronics can be turned
on.
If a diffusion pump fault occurs the system will go to the shutdown sequence.
The user may check for faults on Startup by going to the Diagnostics page and
check Vacuum Status for Fault. Run Tests to Completion and check diagnostics
report for messages.
Diagnostics Page to Determine Diffusion Pump Status
NOTE: The
Vacuum System
status should be periodically checked during
Startup for foreline pressure. The pressure should read below 500 mTorr in 5
minutes and < 100 mTorr after 45 minutes. Higher values may indicate a leak.
Refer to
Troubleshooting
.
