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21. Troubleshooting
If a problem occurs while using the equipment, check it by using the following chart and contact your nearest Shimaden agent.
Problem
Place to inspect
Measures to take
1 No output.
1) Panel LED does not light. Check power. If power is not supplied, check out the power supply side.
If power is supplied, the device may be broken.
2)
is lit in the alarm code
display at the front
display (status display).
There could be something wrong with the circuit or the thyristor may have shorted.
3)
is lit in the alarm code
display at the front
display (status display).
Excessive current may have been produced for some reason.
For pure metal heater or transformer load, set longer slow-up time.
If the alarm lights again, turn the power off, set ramp higher to 0% and then turn the
power back on.
If no longer lit, there might be a problem on the load side. You should therefore check the
load side. If lit, there may be internal failure of the device.
4) Is the control input signal
present?
Check the level by measuring between input terminals with a VOM, etc. If the control input
signal is not present, check the signal supply source such as the controller.
(Linear control input [voltage/current control input]: Between C1 and C2 terminals; contact
2-position control: Between C2 and C3 terminals)
If a normal signal is present, check settings of and connection with external adjusters. If the
connections and settings are correct, the device may be faulty.
5) Output limit is functioning. Check ramp higher limit setting and current limiter setting.
Check the value of the parameter setting screen and whether the external adjuster (VR) to
which the function is allocated has been turned down.
2 Output continues
as is.
1)
is lit in the alarm code
display at the front
display (status display).
The thyristor may be shorted/faulty or the circuit may be shorted.
2) Is the load circuit open?
If the load circuit is open, the panel meter or tester will indicate high voltage.
Check the load circuit.
3) Ramp lower limit setting
is high.
The minimum value for output is not set to zero for ramp lower limit function. Check the value
of the parameter setting screen and position of the external adjuster (VR) to which the ramp
lower limit is allocated. Check VR position on monitor screen VR1
–
VR2.
3 Maximum output
has dropped.
1) Check various output
adjustment settings.
Check parameter setting
(Ramp higher limit selection, Ramp higher limit setting, Variation limit
slow-up, Current limit, Control input scale higher limit setting) values and external adjusters
(VR). Set to
‘
100%
’
and monitor output.
2) Check control input signal. Check if the control input signal is 100%.
3) Check the load current
value.
Check current limit setting, set to 100% and check output and load current. If load current is
at the maximum rated current, the current limit function is functioning.
The load exceeds the rating of the device.
4) Check the measuring
instrument used for the
measurement.
The reading may vary according to the type of meter.
Be sure to use actual value type (True RMS) or moving-iron meter.
If measuring voltage with a conventional digital or analog tester, the mean value is shown as
the actual value conversion, which could result in significant pointing error.
(In the case of a 200 V power supply, pointing error may be as much as 43 V.)
4 External fuse
blows.
1) Are load capacity and
device capacity
appropriate?
If load rate is 100% or more, turn output down.
2) If inrush current from pure
metal heater, etc.,
produces a large load.
Set slow-up time longer. If t
his doesn’t help, replace the device with one with
a larger rated current.
3) If using a transformer.
Set slow-up time longer. Also lighten load relative to transformer capacity.
If malfunction due to noise is possible, either use a noise filter or connect a capacitor (at least
250
V AC, 0.1 μF) between terminals R and U.
