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FAULTS AND ALARMS
10 FAULTS AND ALARMS
Fault/Alarm
Description
Possible Causes
Bus Off
The bus off error in the CAN interface has been
detected.
If the number of reception or transmission errors
detected by the CAN interface is too high, the CAN
controller can be taken to the bus off state, where it
interrupts the communication and disables the CAN
interface.
In order that the communication be reestablished, it
will be necessary to cycle the power of the product,
or remove the power supply from the CAN interface
and apply it again, so that the communication be
reinitiated.
In this case, it will be signaled through the Net LED on
the starter manager. Communication is reestablished
automatically if the P0032 - CAN - Bus Off Reset
parameter has a value of 1.
If the value of the
P0032 - CAN - Bus Off Reset parameter is 0, it will
be necessary to turn the remote unit off and on to
reestablish communication.
- Verify if there is any short-circuit between the CAN
circuit transmission cables.
- Verify if the cables have not been changed or
inverted.
- Verify if all the network devices use the same baud
rate.
- Verify if termination resistors with the correct values
were installed only at the extremes of the main bus.
- Verify if the CAN network installation was carried out
in proper manner.
CANopen Offline
It occurs when CANopen node state changes from
operational to pre-operational.
- Verify the error control mechanisms operation
(Heartbeat/Node Guarding).
- Verify if the master is sending the guarding/heartbeat
telegrams in the programmed time.
- Verify communication problems that can cause
telegram losses or transmission delays.
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