Technical Support

The manual gives incomplete information on how to use an external modbus meter with the inverter, for example it gives wiring diagrams for meter connection but it is missing a number of details,

1) Pinout of Meter_CON port on inverter (does it match the battery RS485 port?)

2) Expected baud rate setting on meter/if this can be configured on the inverter side (there don't appear to be any settings for this)

3) Expected meter slave address

4) If there are any downsides to using an external meter e.g. reduced sampling rate/slower response to loads

In addition, the manual shows the use of an Eastron SDM230 for single phase, however I require the use of an external CT which constrains me to using either an SDM120 or SDM630. Is an SDM120 compatible (I already have one installed from a prior setup, the 230 has a few extra registers associated with split phase operation which should not be relevant in a single phase setup), or will I need to swap to an SDM630?

For reference I'm finding that I'm unable to get the CT to operate accurately across ~30m of CAT6, specifically when system is hovering around zero import/export I'm importing 3-4x what the inverter claims. As this would be at low signal level from the CT I'm assuming the issue is due to noise. Note that the smart meters accuracy has been confirmed by the Eastron meter mentioned above.

UPDATE 25/3/2023

I've been informed that I need a replacement controller board to enable an external meter, however the original concern around CT accuracy has now changed to being a different issue caused by enabling AC coupling of a separate string inverter (this could still be related to CT accuracy), this is currently under investigation by sunsynk, I'll do a separate post on that one...