MODBUS RTU communication with VFD

[Marin]

Hi There!

I am trying to read data and send data to unidrive SK inverter. As for adresses etc on unidrive side, it is all clear, because when i connect with modbus poll software via PC i can read rpm on adress 202 or start/stop drive by sending bit 0 or 1 to adress 629.

I am trying to read same with visio 350-35-RA22 but i am not clear do i use right FB's........so before i'll kill myself with uploading new codes over and over could you check what i am missing?

 

I this example i am trying to read status of adress which is 0 or 1 depending is terminal on VFD on or off.

 

So when i press F1 which is set as SB58 i did out on display to show MB1, but, always 0.......

[Flex727]

Well, first of all, SB 58 should be a Positive Transition contact, not a direct contact.

[Flex727]

And SB 2 should be a contact, not a coil.

[Marin]

9 hours ago, Flex727 said:

And SB 2 should be a contact, not a coil.

That was problem.......

[Ausman]

............so thanks for helping, Flex.

 

Grrrrrrr.

cheers, Aus

[Flex727]

4 hours ago, Ausman said:

............so thanks for helping, Flex.