STP-iX455/iXL455 Series Instruction Manual
13-4
"FAILURE"
LED
(Error message)
Pump
operation
Occurrence
condition
Probable causes Countermeasures
Referred
Section
3 flashes
in red
CNT Overheat Decelerate
and stop
Overheating inside
the control unit
1) High ambient temperature. 1) Set the ambient temperature to 40 °
or less.
4.2.1
2) Insufficient cooling of the control unit
2) Remove obstacle from the ventilation
port.
4.2.1
3) Failure of the air-
accessory)
3) Replace the air-cooling unit 5.2
Steady red
Decelerate
and stop
Rotational speed
increases in brake
or Levitation state
air flows the STP pump.
leakage.
Check the exhaust sequence.
6.1
Decelerate
and stop
The rotation does
not stop after 15
min. into brake
state
Failure of the control unit. Contact Service office.
Decelerate
and stop
1,500 rpm or more
Failure of the control unit. Contact Service office.
Decelerate
and stop
Communication
failure with
magnetic bearing
control board
Failure of the control unit. Contact Service office.
Touch down
*1
E
bearing electric
current
Failure of the control unit. Contact Service office.
DRV Com. Failure
Decelerate
and stop
Communication
failure with motor
control board
Failure of the control unit. Contact Service office.
DRV Overcurrent
Free run
*2
Motor driver over
current
1) Short-circuit or ground fault in the
motor winding.
Contact Service office.
2) Failure of the control unit.
DRV Overvoltage
Free run
*2
Motor driver over
voltage
Failure of the control unit.
*1
: The magnetic bearing output stops and the rotor is descended on the touch down bearing
*2
: The driver output stops and the rotor continue 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.