Confidential
9-21
[ 3 ] Malfunction
When taking countermeasures for malfunctions as described in this section, check connectors for
contact failure before measuring the voltage at the specified connector pins.
M-1
No AC power supplied
Possible cause
Step
Check
Result
Remedy
Supply
voltage
1
Is the correct voltage
present at the outlet?
No
Inform the user that the correct
voltage is not supplied at the
outlet.
Power plug
2
Is the power cord securely
plugged into the outlet?
No
Plug the power cord securely
into the outlet.
Fuse (F1, F2)
3
Is the fuse blown?
Yes If the fuse blows again
immediately after replacing the
low-voltage power supply PCB,
check that there is not a short
circuit somewhere in the AC
power supply line.
Wiring
4
Unplug the power supply
plug. Is there a broken
wire between the AC input
connector of the low-
voltage power supply and
the power plug?
Yes Replace the AC power cord.
M-2
No DC power supplied
Possible cause
Step
Check
Result
Remedy
AC power
supply
1
Is AC power supplied
between connectors CN1-L
and CN1-N when the
power plug is plugged into
the outlet?
No
Follow the same check
procedure of M-1 “No AC
power supplied”.
Wiring, DC
load
2
Turn on the power switch.
Measure the voltages
between the terminals. Do
the measured voltage
satisfy the prescribed
valued in the table below?
Yes Turn off the power switch,
reconnect the connector and
turn the power switch on again.
If the protector circuit is
activated, check the connector,
the wiring from the connector,
and the DC load.
Low-voltage
power supply
PCB
3
Refer to the chart * 1
below.
No
Replace the low-voltage power
supply PCB.
*1
PCB
+lead pin
- lead pin
Voltage
Main CN12-6
CN12-8
CN12-9
CN12-9
Approx. 24V
Approx. 5V