Hi, I've installed a solar system on an airstream caravan for a friend in conjuction with an electrician. I have 
Image Captiona lifepo4 300ah 12v sterling power with built in bms.....the problem seems to be when charging in most states apart from long durations of "float". In bulk ,absorption and partly float I get voltage changes enough to trigger the alarm on the multiplus compact 12/1200. When viewing the solar charger on the app, voltages spike upwards of 16v and power flicks between 5w upto 189w for 600w installed solar power. I've disconnected the panels and measured a smooth dc signal on panel output. When mppt is disconnected there is no alarms from the inverter. Mppt is set to run lifepo4 battery.... I assume the built in bms is at fault but I have changed cell protection settings, etc temporarily without any major effect. Could anyone shed any light please many thanks. 
