My Solar Battery with Hybrid Inverter not showing correct import / export reading

Have been running My Solar for a while successfully, just added batteries to a hybrid inverter and set up My Solar Battery. Looks like all the feeds are set correctly, but on running it, the import/export is not correct and does not match the import/export reading on My Solar.

It would appear that it is treating the battery_charge feed as coming from the grid, rather than (invisibility as far as emonPi’s CT clamps are concerned) direct from inverter to battery.

Is there a specific configuration needed to use My Solar Battery with a Hybrid inverter?

Thanks.

Is anyone using MySolarBattery with a hybrid inverter? If so, any advice appreciated!

Hybrid battery setups don’t play nicely with CT clamps as the energy is kept on the DC side of things, ie inside the inverter.

CT clamps monitor AC flows.

Similar issues discussed here.

Thanks, but was not attempting to use CT clamps on a DC circuit, as they’re obviously just for AC.

My configuration is that I have the regular 2 CT clamps on the emonPi, one measuring grid and one measuring inverter output - the latter will show the inverter output less any battery charging as the charging from PV is done within the inverter, being hybrid.

I have the ‘battery charge’ and ‘battery discharge’ feeds derived from posted MQTT data from the battery BMS, together with SOC.

Is it possible to use MySolarBattery with some config adjustments - seems strange no one has attempted this already?

My Solar Battery is working fine with my hybrid inverter, though I get all my values directly from the inverter’s MQTT (no clamps) so I’m not sure that will be much help to you.

I think the key is ensuring that all the inputs to My Solar & Battery app are correct, which might require combining other feeds together:

  • use = inverter output + grid (assumes grid goes negative when exporting)
  • solar = inverter output + battery charge - battery discharge (unless you measure solar directly)
  • solar_direct_kwh = inverter output - grid export - battery discharge

Thanks Tim, that was exactly what I was looking for.

Have implemented your suggestions and it is now working great. I just also needed to “calibrate” (downwards) the battery discharge figure (which was derived from BMS DC volt and amp measurements) to take into account the inverter losses (i.e. in order for the battery discharge to better match the home use and prevent an erroneous ‘export’ reading.)

Thanks again!

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