Edwards SCU-800 - Page 128

SCU-800 Control Unit for Turbomolecular Pump
MT-49E-101-G
Page 116
7
MAINTENANCE
Referred
section
Instruction
Manual
(B)
3.11
*1
The driver output stops and the rotor continues rotating by inertia.
It may take several hours to stop. To stop the STP pump quickly,
close the vacuum valve at the outlet port
flange and introduce gas from the purge port into the STP pump.
Table
36 - Error
messages after self test (continued)
Countermeasures
1. Use the maximum
working pressure or less.
2. Use the allo
wable backing
pressure or less.
3. Check the vacuum piping
system for leakage.
4. Check the backing
-pump
for its capacity and START state
.
(use a backing
-pump with
the recommended capacity or more)
Contact Service office.
Contact Service office.
Contact Service
office.
Contact Service office.
1. Connect the cable
correctly. If the cable is not locked, lock it securely.
2. Set "
Leak
Valve Option"
to "DISABLE".
Probable causes
1. High pressure at the inlet
port.
2. High pressure at the outlet
port.
3. Leakage of the piping
system.
4. Failure of the
backing
-pump.
Failure of the SCU
-800.
Failure of the SCU
-800.
Failure of the SCU
-800.
Failure of the SCU
-800.
1. Disconnection of the
emergency vent valve cable.
2. Incorrect setting of the
emergency vent valve.
Pump operation
Decelerate
and stop.
Free run
.
*1
Free run
.
*1
Touch down. The magnetic bearing output stops and the rotor is descended on the
touch down
bearing.
Decelerate and stop.
Decelerate and stop.
Occurrence condition
ACCELERATION state continues for approximately 30 min
utes.
Driver overvoltage.
Failure of the driver circuit
.
Abnormal CPU
operation
.
Serial communication failure.
Disconnection of the emergency valve cable.
LCD Messages
Driver Overload
Driver Overvoltage
Driver PWM Trouble
DSP Initialize Fail
DSP
->PCB Co
m
Fail
E.valve disconnect