All Products - Load Readings Incorrect When Using Third Party Batteries

When using third party batteries i.e. batteries made by a manufacturer other than Sunsynk which are not on our approved compatibility list, there have been instances where we have observed inaccurate fluctuations in oad readings when the batteries are charging and/or discharging.

Installers should avoid choosing batteries which are not listed on Sunsynk's battery compatibility list as they are not tested to be 100% compatible with Sunsynk inverters and are at risk of not performing or communicating properly.

Cause

The most commonly identified cause is that electrical noise originating from the batteries causes interference which affects CT readings or third party metering equipment. This can result in significantly higher load readings (sometimes over 3 times what it should be reading) and can also cause negative load readings even when the CT clamps are in the correct orientation.

How To Test

The first test would be stopping the batteries from discharging by setting the target SOC in the active system timer to a value higher than the current SOC of the batteries and ensuring the grid charge for that timer is deselected. You must also check the grid charge % in the Battery Settings menu if the current battery SOC is low as this can cause grid charge even when disabled in the timers. If load readings return to a more typical 'normal' value then monitor for a period of around 30 mins or more to check that the now correct readings remain stable - this can be monitored in the Energy Generation graph or Custom Data in Sunsynk Connect. 

If the readings remain correct and stable then the timer settings can be readjusted so that the battery starts discharging/charging again 

Third Party Metering Kit

The issues has been observed with both direct CTs and third party metering kit e.g. Eastron Meters so this is not considered to be a potential solution to the problem.

Solution

This problem can be avoided altogether by using listed compatible batteries, but in some instances where wrapping both battery power cables as well as the BMS communications cable around ferrite rings 3 times has stopped the interference with the load readings. 

N.B. this is not a guaranteed fix but it is a potential one.