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I setup an ATV 320 V.F.D. in IO profile mode,
as I started the motor I receive status word from V.F.D. :
Ready to switch, Ready to operate and error.
While the motor is running we get Boolean state "FALSE" on signals as if V.F.D. is not ready to switch and it is not ready to operate.
We don't get error information, V.F.D. just stops the motor and waits for the next command.Ready to switch and ready to operate signals stay FALSE until i reset "RUN" bit in command word. After that they go back to state "TRUE".
This all happens in process where we simply want to run our motor constantly without turning off, and we don't have any idea why would it suddenly in the running state stop being ready and waiting for next command as if his command is always be running..
Could anyone help me with this one?
Are you sending command through modbus from PLC?
if yes, make sure this command always send periodically. if it doesn't, VSD will back to ready state for safety reason.
There is a communication control on Modbus, the ATV controls that there are requests sent periodically. Normally if you read the status of the ATV periodically, it is enough to maintain the control of the communication.
Here after an extract from the documentation:
Hello, thank You for your reply,
I am sending the command word via Profinet every communication cycle. The drive is fitted with VW3A3627 module. 2 out of 14 drives are the only ones to have this problem.
you can try to switch over the 2 VSD IP address with a good one.
if the problem appear on new IP (old VSD) the source of problem could be on VSD configuration.
if the problem appear on old IP, then your problem could be on your PLC setting/program.
Do all of the drives have identical configurations? (the answer to this should of course be 'no', since they likely have different motors / different node addresses)
But importantly, is the SLL [Modus fault Mgt] field set to 'no' on ALL of the drives?
Make sure that safety is afforded in a more robust manner than just using this setting of course.. otherwise death may occur.