Hi
I have had my 48V 5k Multiplus setup for over 2 years in my house and had no real problems. I want to move it out of the house into a shed near the incoming supply. I’ve had a child and other things and my memory has faded from when I installed it. I think I’m over complicating it, so should hopefully be an easy one.
Currently I have one mains connection to the Multiplus (AC in) and use a meter (ET112) on the supply to set the incoming power to zero in the day and then charge over night. My thinking is to insert the Multiplus into the main supply. Whole house on AC out 1.
- I have a heat pump and car charger - nighttime max total current will be 42A*. Am I right in saying there will only be 8A left for the battery to charge? Which will be a little less than 2kVA (UK 240Vac). *Never seen the heat pump draw more than 10A and 32A car charger.
- Two solutions; limit the car charging current to around 20A or;
- put a by pass switch for the car charger (on a separate consumer unit).
- Currently my grid connection is not balanced to 0W, it fluctuates as loads come and go from the house.
- Would this new setup with the inverter/charger being directly inline solve this issue?
- Currently exporting around 30kWh a year and therefore importing around the same too. So should save a little on the electric bill.
Bonus questions, not important:
- On my current setup, because connecting the inverter only to the ‘AC in’ connection. When there is a power cut, the inverter only outputs on ‘AC out 1’. So I had a transfer switch to connect the AC out 1 to the house during a power cut. I isolate the house from the grid first before switching over. This worked well and have only really used it properly this winter when we had a storm and lost power for 4 hours.
- I couldn’t run the heat pump. When it kicked in it tripped the RCBO connected to the inverter. This is 50A, so my guess is earth leakage somehow.
- My question is, in ESS mode what is the status of the PE to neutral relay, called relay H in section 4.4 in the manual but in the diagram in the appendix not labeled. Guessing it closes when it senses no mains power on AC in. And guessing during startup the heatpump puts a little current on the earth and maybe because the power is back feed through the RCBO it is more sensitive.
- Rough diagram below. The heat pump will probably be earthed elsewhere.
Thanks in advanced!
