The "Bus" LED on the CTD shows when there is bus activity.A short heartbeat is shown every 5 seconds.When a module 'wakes up' the bus, the LED will be red.But it must turn off after a few seconds.However, if this "Bus" LED is continuously lit, this is probably due to a contradictory configuration or caused by a (broken) module on the bus.
In order to eliminate this last option, simply disconnect all bus wires and check the led...
A possible contradictory configuration can be:An input that is set as "Normally open" or "Normally closed" can not be forced.The same applies to an output that is connected to a detector.Or conflicting logic was used...This continuous bus communication must certainly be remedied.
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