The pump does not respond in mul- drop mode
Cause The mul-drop is disabled.
Remedy Make sure the pump has a mul-drop address and that commands are sent using the mul-
drop protocol.
The green Normal LED does not light or the pump is not rotang at full speed or the pump
fails whilst running
Cause The inlet pressure is too high.
Remedy Reduce the pumping load or check for a gross leak into the system.
Cause The pump is running too hot.
Remedy Increase the cooling to the pump. Change from air cooling to water cooling (refer to Table 38
on page 86 for maximum inlet pressure and cooling requirements).
Increase cooling water ow or decrease the water temperature or do both.
Check that external heat sources (such as system bakeout heaters) are not excessive.
Cause The rotor does not rotate freely.
Remedy The pump bearings may be damaged. Contact the supplier or Edwards.
Ulmate pressure cannot be reached
Cause Pressure is limited by water vapour.
Remedy Bake the system and pump.
Cause The vacuum gauges are contaminated.
Remedy Clean or replace the vacuum gauges.
Cause Pumping speed is insucient due to poor conductance between the pump and the gauge or
the chamber is too large.
Remedy Increase the conductance or reduce the volume.
Cause Inlet pressure is > 0.5 mbar (50 Pa).
Remedy If the interstage inlet pressure is too high, inlet pressure at the turbomolecular inlet is
increased; ensure that the interstage inlet pressure is < 0.5 mbar (50 Pa).
Cause The backing pressure is > 10 mbar (1x10
3
Pa).
Remedy The backing pressure may be too high. Check for backing pipeline leaks. If the throughput is
high, a larger backing pump may be required.
Cause The high vacuum area of the system is contaminated.
Remedy Clean the high vacuum system.
Cause Check the rest of the system for leaks and contaminaon.
Remedy If found, repair the leaks and clean the contaminaon.
Cause The inlet pressure is poor.
B8G0-00-880A - Troubleshoong
Page 66
To Next Page
Loading...
Need help?
General
