Unusual Check - Mitsubishi LE-30CTN Instruction Manual

11. Inspection and Maintenance
11.4

Unusual check

• When an error occurs during the test run or actual operation, solve the problem referring to the following
table.
Item
When the power is
turned on, the power
indicator LED(3) is not
lit.
When restarting after
stopping the material,
the tension reading goes
beyond the scale from
the beginning.
Fluctuating tension
control
After replacement of the
material, an extremely
high or low tension is
applied.
On the display, the
tension value or the unit
of the tension flashes.
The output increases
while the machine halts.
The control output signal
will not be output.
The contact signal and
the analog voltage signal
are not input properly.
Problem
• Make sure the supply voltage between the terminals [PSL] and [PSN] is 100
to 240VAC (+10% to -15%), 50/60 Hz. If this value is not correct, perform the
correct wiring.
• The fuse may be melted by insertion of foreign objects or abnormal loads. If
simply replacing the fuse may not solve the problem. Contact our service
department.
• Turn ON or OFF the [RUN] input signal depending on the run/stop status of
the machine. If the [RUN] input signal is kept at on status, restarting
operation may send out the maximum control output, and an extremely high
tension may be applied.
• When stopping the machine, if the turning-OFF timing of the [RUN] input
signal is delayed, the control output may be extremely increased, and an
extremely high tension may be applied at starting operation. To prevent this
problem, be sure to turn OFF the [RUN] input signal when stopping the
machine.
• Check whether similar fluctuations occurs during manual operation.
• Fluctuations during manual operation is generally caused by changes in
tension as a result of machine vibration, mechanical loss, etc. In this case
please check the machine.
• If fluctuations do not occur during manual operation, this is generally caused
by high control gain set by the LE-30CTN tension controller. In this case,
please adjust the control gain factor refer to Sec. 5.5.
• Check that the output set for the OFF status of the [RUN] input signal is
optimum for the reel diameter of the replaced material.
• Check that the output memory fluctuation is canceled after stopping the
machine. - - - - - - - - - - Refer to Sec. 5.1, 5.2.
• The tension signal from the tension detector is too high. The applied load
may exceed the rated load of the tension detector. Lower the tension set
value.
• Check the rated load of the tension detector. If no problem is detected,
increase the full-scale tension value. (After changing the full-scale tension
value, be sure to tune the zero point and the span.)
• The [RUN] input signal may not be turned OFF.
• While the machine is stopped, be sure to turn off the [RUN] input signal.
• Turn on the control output using the output ON/OFF key(15) on the panel. If
this keying cannot turn on the control output, check the rated current of the
clutch/brake (should be 3 A or less) and the wiring condition (should not be
shorted, etc.).
• When the load line is shorted, eliminate the cause. After that, keep the
power at the OFF status for a few minutes, and then turn on the power
again.
• Disconnect the powder clutch/brake line, and check that the voltage is
output between [PP] and [PN]. If no voltage is output, the LE-30CTN
tension controller is defective.
• When [TOUT] and [AOC] are used, check that the load resistance is 1kΩ or
more.
Referring to Sec. 8.4, check the following items
• Compare the ON/OFF status of the input contact signal with the status
shown on the monitor screen. In addition, check the input contact for
poor contact. If the input signal is properly turned ON and OFF but the ON/
OFF status is not displayed on the monitor, the LE-30CTN tension
controller is defective.
• Compare the voltage of the analog input terminal with the voltage value
displayed on the monitor. Also check that noise is not influencing the input
line.
11.4 Unusual check
Disposal
47