I have recently installed an ESS set up with Mulitplus 2 48/1000 and 4x Pylontech US5000. Broadly system working fine but I am disappointed with the following:
1) At night when the SOC falls to the set minimum of 85% the batteries go into 'idle' and the grid goes straight through to run the house loads. Come daytime, when the AC coupled PV produces power the batteries are VERY slow to wake up and start charging. The surplus PV power is only 100W to 200W but it took 5 hours before the batteries 'woke up' today. Is there a 'setting' that affects this - I cannot find one.
2) The unit is much noisier than I expected. I have had an offgrid system elsewhere for over a year (based around the 48/5000) and was surprised with that at the noise of the cooling fan. I had accepted that these units are noisy under load. But the off grid system is almost silent under low load conditions at night (eg 60W) and I was expecting similar behaviour here. My 48/10000 multiplus (firmware version 496) was sized to have ample spare capacity under all normal conditions and yet produces a significant mains hum/buzz all the time even under very low load conditions (eg 200W). This is very annoying late evening and during the night. It varies little whether the loads are being powered with the grid switched straight through or from the batteries with the grid switched off. Surely it shouldn't produce a disturbing hum when simply ticking over.
3) Not a problem but puzzling. At low grid powers, eg 120W (either direction), the current reading is way out, eg 1.6A (should be nearer 0.5A). Is this just a sensitivity issue? If so why is the current quoted to 0.1A?
Hoping someone can help me improve on 1) and 2) above. I can find nothing on the forum.
Thanks,
David
