Diagnostic LEDs

The four green RUN LEDs indicated the operating state of the terminal channels.

Diagnostic LEDs 1:
KL3404/KS3404 and KL3464/KS3464 - LEDs

Meaning of the LED displays

LED

Color

Channel

State

on

off

Run1

green

1

normal operation

A watchdog timer overflow has occurred. The green LEDs go out if no process data are transferred between the controller and the Bus Coupler for more than 100 ms.

Run2

2

Run3

3

Run4

4