160
10.6 Specific Problems
I/O signals cannot be exchanged with the PLC.
Cause: [1] The 24-V I/O power supply is connected in reverse.
[2] If the problem is with an output circuit, a circuit component may have been damaged due
to a large load that caused the current flowing into the circuit to exceed the maximum
current.
[3] Contact failure in the connector or relay terminal block on the PLC end.
[4] Contact failure between the female pins in the flat cable connector and the male pins on
the controller due to expanded female pins.
Action: Check the connection condition of the power supply and connector, as well as the load on the
output side.
If the cause is identified as [1] or [2], the controller must be replaced. If there is a possibility of
[4], the flat cable must be replaced. Please contact IAI.
Warning: When performing a continuity check of the flat cable, pay due attention not to expand
the female pins in the connector. It may cause contact failure and disable normal
operation of the controller.
The ALM lamp illuminates when the power is input.
(An alarm is present, or an emergency stop has been actuated or the motor power cut off.)
* If the ALM output signal is OFF, an alarm is present. Connect a PC or teaching pendant to check
the nature of the error and then remove the cause.
* If the ALM output signal is ON, the emergency stop circuit has been actuated. Check the following
points, among others:
[1] Is the emergency-stop switch on the operation panel pressed or any necessary interlock
released?
[2] Is the emergency-stop switch on the teaching pendant pressed?
[3] Is parameter No. 42 (Enable function) enabled by mistake by connecting a teaching pendant not
supporting the enable switch?
[4] If multiple controllers are connected, is the crossover wiring correct?
The SV lamp does not illuminate when the servo ON signal is input after the power was input.
(The servo does not turn ON.)
Cause: [1] Contact failure of the flat cable
[2] Faulty controller
Check the servo ON signal (SON) on the I/O monitor screen of the PC or teaching pendant.
If the signal is input, probably the controller is faulty. Please contact IAI.
To Next Page
Loading...
Need help?
General
