HTC 420 VS User Manual page 37

HTC 420 VS
Error code Cause
SCF SCF = Short circuit in the motor
Due to a short circuit in the motor or
the motor cable. May also be due to
an earth fault.
tnF tnF = Autotuning fault
May arise if the motor has been
replaced by the wrong motor, which
is outside the norm values for the
converter. May also arise if the
motor is broken.
OLF OLF = Overload motor
Occurs when the motor is
overloaded for a prolonged period.
The motor protection in the
converter trips in order to protect
the motor.
OSF OSF = Over-voltage
Mains voltage too high or
disturbance in the mains supply.
May occur if large motors/machines
are switched on or off in the
vicinity. May be due to non-CE
marked equipment.
USF USF = Under-voltage
Voltage too low due to large number
of consumers using the network.
Temporary drop in voltage. Long
and/or weak cables may also cause
this fault.
ObF ObF = Operating load when stopped
Arises if the grinding discs are
running when the machine is to be
switched off.
3.0
Electronic Error Codes
Action
Check the wiring and, if necessary,
the motor isolation. Test by
loosening the motor cable and
starting the frequency converter to
see if the error code appears. If this
occurs, the fault is in the frequency
converter, otherwise the cable or
motor is broken.
Check the motor. Replace the motor
with an original motor.
Switch off the machine. The motor
protection must cool.
Wait 8 minutes before the machine
is restarted.
Measure the supply voltage. Change
the socket. The max. permitted
supply voltage is 240V + 10%.
Replace the socket or remove some
of the consumers from the network
(welding, etc. causes such faults).
Check the power supply to the
machine, i.e. the fuses and cable. If
the machine still does not function
after the power supply has been
checked, the fault may be due to a
fault on the contactor in the machine
or in the control panel. In this case,
contact HTC Service Centre.
29