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Controlling AIMS/SG/Renogy Inverter-Chargers with BMS

bri2k

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Joined
Sep 14, 2020
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Hi,
I'm looking for an economical inverter-charger for my van build and i've been eyeing the SunGoldPower 3kw inverter-charger. One important factor is that I'm using an ElectroDacus BMS and I want to be able to disable the invert (Low voltage) and the charger (high voltage) independently. The Victron Multiplus is the only inverter-charger that I know supports that but I think the AIMS/SG/Renogy units could be made to work as a low cost alternative. For disabling the inverter I can use a SSR in place of the regular on/off switch. For the charging, these units have a rotary selector switch that allows you to choose between "no charging" and the various battery type settings. That seems like a great place to hack in a relay that can be controlled by the BMS. Have any of you looked into doing this? The main issue I can think of is if the rotary switch can't be changed while the unit is on and charging. Thoughts? Thanks

Amazon Link to Sungoldpower 3k inverter-charger
 
I solved the problem of the inverter/chargers by using 2 DC-AC SSR one on the AC in and one on the AC out this allows one to still work if the other is cut off. It does leave the inverter on though with an "idle" draw if the battery gets low when there is no AC for charging
 
I solved the problem of the inverter/chargers by using 2 DC-AC SSR one on the AC in and one on the AC out this allows one to still work if the other is cut off. It does leave the inverter on though with an "idle" draw if the battery gets low when there is no AC for charging
The AC SSRs are a good idea if there's no other way to control the inverter. In the case of these units, they have a rocker switch that you can place an DC SSR inline with so that solves the idle consumption issue.
 
Two questions for anyone who might have one of these inverters:
  1. Does the charger still operate if the inverter is switched off?
  2. Would someone be willing to try switching the battery selector switch between your selected battery type and "no charge" while the unit is charging? I'd like to know if switching to "no charge" immediately stops charging and then what happens when you switch back to your battery type.
Thanks
 
Does the rocker switch turn everything off or just Inverting?
That's what I need to find out. If the rocker switch turns everything off I'm not too worried because I would plan to use the rocker switch only to protect against low voltage. Presumably, that would only happen when there is no AC shore power available so the unit wouldn't be charging anyway. It might be an issue when I plug back in to AC but I could manually bypass the SSR at that point.

Also if the rocke switch only turns inverter off there will still be an idle draw hopefully less though.
That's a good point to think about. I would assume, possibly incorrectly, that the charger would be powered by the AC shore power and would only draw load when plugged in to AC power.

I guess either way, if the battery type switch can actually be hacked to turn charging on/off, whether the inverter switch controls both the inverter and charger doesn't matter too much. The only issue is that I would need to make sure the inverter is switched on when AC is available so it will charge the battery, if the rocker switch controls both inverting and charging.
 
Did you find a solution to this issue? I'm also putting in a Sungold 3Kw inverter in my RV and facing similar challenges with controlling the inverter and the charging. I'd specifically be interested if you found out if the battery selector can be hacked and what your final setup ended up being.
 
Not sure if you found an answer. The remote switch RJ45 port can be used to control the mode of the inverter. There is a YouTube video by a guy with a 10Kw AIMS inverter. I found the same jack on my 2K AIMS inverter. By placing a relay between pins 3 and 5, setting the switch on the inverter to off, you can turn the inverter on/off via the relay. Mine draws about 23 watts continuously. With the wonderful weather here, it can be days or even weeks without much sun.
 
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