CubesAreShapes
New Member
- Joined
- Aug 27, 2022
- Messages
- 14
Hello,
I am wondering if anyone else has done this already or has some feedback about this idea.
As you all know, Growatts use a lot of power compared to other inverters (see https://diysolarforum.com/threads/idle-no-load-consumption-specs-vs-your-personal-observation.31747/). I have a Growatt SPF 12000T DVM-US MPV and it consumes ~.8A from each of my four 48V batteries in idle - ~153W at best. This is about 76AH @ 48V for a day of idle - which is a massive 19% of my battery capacity - whether or not I'm even using any electricity. The power save mode does not work for me because 1) Does not play well with my energy efficient fridge that requires intermittent power 2) I am concerned about my electronics with the pulsing - I see one of my bulbs get brighter every 3 seconds 3) My regular energy usage seems to be low enough for it to turn off (don't know what that is exactly, maybe 100-150W, but I can be on the PC with my Starlink satellite running and it starts turning off and on - at times I have resorted to turning on an LED light just to keep it from cycling). I have this giant inverter because I have a standard 240V split-phase range and heat pump. I've realized with these cloudy Canadian winters that I cannot rely on the heat pump in the winter (going to be using wood/propane for winter heat), so I'm mostly running this inverter just to turn my stove on whenever I want. 95% of the time I am using ~200W or less (Starlink satellite, some LED bulbs, monitor, laptop).
The plan:
Buy a Victron Energy Phoenix 1200VA 48-Volt 120V AC Pure Sine Wave Inverter which uses 10W idle, and a 2 way switch to choose between the inverters. That way, I simply switch it to the Growatt inverter before cooking (bonus is some arduino controlled thing or an out of the box AC switch that has wireless capabilities as the switch would be about 200ft away in my shed but I digress) or in the summer when I have ample energy I could leave it on and run the heat pump for AC. Best of both worlds. Fortunately, even when the Growatt inverter is off, it'll come on and charge up my batteries if the PV input is sending some power, but that means I don't want the switch between the inverters and the batteries (like originally planned - almost even bought the Bluesea DC 2 way switch), rather after the inverters and before the AC breaker panel seems like the best place.
However, I'm not exactly sure the best route to accomplish this. Currently the Growatt is wired into a breaker box as the mains supply, and goes through a 60A breaker straight to my house panel. With the Phoenix inverter, should I also just have it coming right into the mains (I suppose it would be connected with the Growatt output wires before the box and one set of wires going into the box in this case)? My plan is also to just send the 120V single phase down both conductors (that way I don't have to make sure all my 120V breakers in the house are on the same leg). I'm not sure how my 240V split phase appliances would react to this if I did indeed turn them on (could it damage them?). Also very curious what would happen if I had BOTH inverters on at the same time - would the "phase" of each leg remain perfectly in sync with the added power from the Pheonix? My suspicion is no, turning to a MAYBE if it distributed equal power to each leg which is very unlikely. Maybe the Growatt would supply all the power and the Pheonix wouldn't detect a load? This seems very circumstantial though. If Growatt power saver mode worked better then maybe this could be a better option (Growatt could just kick on automatically when I start using the stove or need more power! That would be incredible). Is there a smarter way to do this that I'm not thinking of. Can anyone think of any unintended consequences of having both inverters wired up like this? Things I should be careful of?
Hopefully this ultimately saves me a lot of idle energy - even right now I'm using about 150W so the Growatt is doubling my usage. Don't want to talk about it's usage compared to when I go to bed in a few hours (turning it off at night isn't really an option as I run a 120V fridge).
Thanks for reading!
I am wondering if anyone else has done this already or has some feedback about this idea.
As you all know, Growatts use a lot of power compared to other inverters (see https://diysolarforum.com/threads/idle-no-load-consumption-specs-vs-your-personal-observation.31747/). I have a Growatt SPF 12000T DVM-US MPV and it consumes ~.8A from each of my four 48V batteries in idle - ~153W at best. This is about 76AH @ 48V for a day of idle - which is a massive 19% of my battery capacity - whether or not I'm even using any electricity. The power save mode does not work for me because 1) Does not play well with my energy efficient fridge that requires intermittent power 2) I am concerned about my electronics with the pulsing - I see one of my bulbs get brighter every 3 seconds 3) My regular energy usage seems to be low enough for it to turn off (don't know what that is exactly, maybe 100-150W, but I can be on the PC with my Starlink satellite running and it starts turning off and on - at times I have resorted to turning on an LED light just to keep it from cycling). I have this giant inverter because I have a standard 240V split-phase range and heat pump. I've realized with these cloudy Canadian winters that I cannot rely on the heat pump in the winter (going to be using wood/propane for winter heat), so I'm mostly running this inverter just to turn my stove on whenever I want. 95% of the time I am using ~200W or less (Starlink satellite, some LED bulbs, monitor, laptop).
The plan:
Buy a Victron Energy Phoenix 1200VA 48-Volt 120V AC Pure Sine Wave Inverter which uses 10W idle, and a 2 way switch to choose between the inverters. That way, I simply switch it to the Growatt inverter before cooking (bonus is some arduino controlled thing or an out of the box AC switch that has wireless capabilities as the switch would be about 200ft away in my shed but I digress) or in the summer when I have ample energy I could leave it on and run the heat pump for AC. Best of both worlds. Fortunately, even when the Growatt inverter is off, it'll come on and charge up my batteries if the PV input is sending some power, but that means I don't want the switch between the inverters and the batteries (like originally planned - almost even bought the Bluesea DC 2 way switch), rather after the inverters and before the AC breaker panel seems like the best place.
However, I'm not exactly sure the best route to accomplish this. Currently the Growatt is wired into a breaker box as the mains supply, and goes through a 60A breaker straight to my house panel. With the Phoenix inverter, should I also just have it coming right into the mains (I suppose it would be connected with the Growatt output wires before the box and one set of wires going into the box in this case)? My plan is also to just send the 120V single phase down both conductors (that way I don't have to make sure all my 120V breakers in the house are on the same leg). I'm not sure how my 240V split phase appliances would react to this if I did indeed turn them on (could it damage them?). Also very curious what would happen if I had BOTH inverters on at the same time - would the "phase" of each leg remain perfectly in sync with the added power from the Pheonix? My suspicion is no, turning to a MAYBE if it distributed equal power to each leg which is very unlikely. Maybe the Growatt would supply all the power and the Pheonix wouldn't detect a load? This seems very circumstantial though. If Growatt power saver mode worked better then maybe this could be a better option (Growatt could just kick on automatically when I start using the stove or need more power! That would be incredible). Is there a smarter way to do this that I'm not thinking of. Can anyone think of any unintended consequences of having both inverters wired up like this? Things I should be careful of?
Hopefully this ultimately saves me a lot of idle energy - even right now I'm using about 150W so the Growatt is doubling my usage. Don't want to talk about it's usage compared to when I go to bed in a few hours (turning it off at night isn't really an option as I run a 120V fridge).
Thanks for reading!
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