Sharing rs485

[Greengoat]

Needing to install export limitation to 3 of my Inverters, to start things simple let's just look at the two Solax 6kw X1 Inverters.
They have the option of CT clamp or Chint DSU666 meter on Rs485. The Chint meter is more obtainable so have gone with that option for now, but using a single meter can the rs485 signal cable be connected in Parallel between the two invertors. Solax couldn't say so have tried it but getting fault on one inverter.
With no connection the inverter shows constant meter fault. With Parallel connection one is fine and happy the other shows a meter mault every few seconds and won't start up. If either unit has the signal cable pulled the other is happy.
Am I missing something or should I just bite the bullet and get second meter feeding each unit with its own? With so many systems my meter cupboard is getting full of meters and Ct clamps!

 

[Quattrohead]

Yes that is how you connect RS485, but you have to terminate it with 120ohm resistor. Some electronics will auto terminate for you, some have a DIP switch and some are too lazy/cheap.

 

[cods4]

You may also need to check what address they are communbicating on. I understand each device on the modbus network has to have a unique address, and they normally just use numbers 1,2,3,4....
So it is possible that your meter and one of the inverters are on the same address? I remember seeing a setting on the Chint DDSU666 where you can change the address.

On a side note, does your chint meter use a CT or is it a straight through type meter? I have one of each type of Chint meter but I'm not sure what CT ratio I should be using with the CT type meter as I cant see how to set it in the meter.

 

[Greengoat]

Thanks, address issue could be likely, I will check on Monday.

 

[bhups]

Did you manage to get this sorted? I will be soon expecting to get this set up and I cannot find an answer for it too.