ModbusTCP comms with Sd750

[DrdP]

Good day Everyone

I am from New Zealand and new to Nodered. I am trying to communicate with a Power Electronics SD750. I have made the following flow to see what I can read. Any register that I choose just stays zero in the debug pane. I have added some pictures as a reference to what I have made. Any advice would be immensely appreciated

Thank you
D

[mtoko]

Just some advice to get you started, try adding a Modbus response node to the bottom output of the modbus read node. This will show if there is communications and what the raw data is.

[rromele]

hi,

if you share your flow code surely someone can help you or give you some advice.
R.

[DrdP]

Hi and thanks for the suggestions.

I figured out what the issue was. Basically some modbus peripherals use a native adressing or a more pointed addressing type.

On Power Electronics drives it automatically knows that reading the holding registers start at address 40000. To read address 42061(AI1 raw value) you need to enter 2061 in the address field of the read modbus node.
I hope this makes sense.
D