IAI America PCON-CY - Manual (Page 116)

106
7. T
roubleshooting
7.5 Common Problems and Recommended Actions
z I/O Signals Cannot Be Sent or Received to/from the PLC.
Cause: [1] The 24-V I/O power supply is connected in reverse polarities.
(In this case, input circuits are not affected, but output circuits will be damaged.)
[2] If an output circuit presents this problem, electrical current exceeding the maximum current flowed due to a
large load and a circuit component was damaged.
[3] Poor contact at the connector or relay terminal block on the PLC side.
[4] The female pins on the flat cable connector are bent outward, thus causing contact failure with the male pins
on the controller connector.
Action: Check the connection condition of the power supply and connector, as well as the load on the output side.
If [1] or [2] is suspected, the controller must be replaced. If [4] is likely, the flat cable must be replaced. Either
way, contact IAI.
Warning: When checking the continuity of the flat cable, exercise due caution not to bend the female pins on the
connector outward. It may cause contact failure, resulting in malfunction.
z The ALM Lamp Illuminates after the Power Is Turned On.
(An alarm is present, emergency stop is actuated, or the motor power is 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 remove the cause.
* If the ALM output signal is ON, the emergency stop circuit is actuated.
Check the following items:
[1] Is the emergency stop switch on the operation panel pressed by mistake? Is the necessary interlock canceled?
[2] Is the emergency stop switch on the teaching pendant pressed by mistake?
[3] Is Parameter No. 42 (Enable function) enabled by mistake when a teaching pendant is connected that does not support
the enable switch?
[4] If multiple controllers are linked together, are they wired correctly?
z After Turning On the Power, the SV Lamp Does Not Illuminate upon Servo-on Signal Input.
(The Servo Does Not Turn On.)
Cause:
[1] Contact failure of the flat cable
[2] Faulty controller
Check the servo-on signal (SON) in the I/O monitor screen on the PC or teaching pendant.
If the signal is input, the controller may be faulty. Contact IAI.