MKS HPS 937A Series, Руководство по эксплуатации и техническому обслуживанию владельца, Страница: 100 / 108

937A Multi-Sensor System
B.2
Place the pump away from the suspected leak source and place the
sensor between the leak and the pump to reduce the sensor response
time. Vacuum tubing between the suspected leak and the sensor
should be as short and wide as possible to shorten the time required
for the probe gas to reach the sensor.
If the above leak detection method fails to indicate the location of a leak,
unexpected high pressures may be caused by a virtual leak, i.e., outgassing
of a system component. You can locate outgassing parts, or “virtual leaks,” as
well as true gas leaks using the
rate-of-pressure-rise method below.
1 With the Controller on, pump down the system to a base pressure
2 Close a valve to isolate the pump.
3 Measure the rise of the pressure over a time interval. A very fast rise
indicates a leak.
4 Repeat this procedure as often as necessary.