RV solar system 48v Growatt ? about using a all in 1 and charging my DIY battery with it.

motomarc

New Member
Joined
Feb 16, 2021
Messages
15
I am a newbie I have been doing research and figuring out size of solar panels and battery I need for my RV.

My ? is with a all in 1 inverter like the one I am looking at Growatt 3000 ES it has built in mppt.
if I am using my own Daly BMS on my 48v DIY battery do I still just hook + & - to the battery input on the Growatt ???
I am guessing set the Growatt to Lifepo4 parameters and it will push the proper voltage to the battery & my BMS will keep it in balance etc is this correct??
any images of a all in 1 tied to a DIY battery 48v would be great.

This is what I have specked out for my system.
any recommendations would be great.
especially if you can get me to 250v PV with less then 7 panels measuring 65x39x2 each :rolleyes: things are big.
smaller panels with same voltage would be really nice. saves me space on the roof.
4qty - 60v voc or vmp panels would be the best thing I could have I think, putting me right at the 240v .

Back to the plan.
this is for off grid use when not hooked to shore power.
the native 12v system in RV will not be touched it will be left alone in the RV.
the plan is to have the solar system inverter as as separate power bank powering directly into 1 of the - 110v pole/legs of the RV shore power system / breaker box eliminating issues of 48v to 12v step down & still have he ability to use factory electric RV system.
this will allow me to power tv, the native12v converter and small appliances as well as 1 AC unit that pulls under 10 amps.
maybe in the future if need more capacity I will go 2p & power the 2nd 110v pole/leg in the breaker box for more air conditioning with another Growatt 3000 ES, if I can afford it as well LOL.

I am going with a 280ah or bigger lifepo4, DIY 48v battery bank Daly 150AMP BMS , 2/0 wires
Jinko panels 265watt x 7 total output 256v can't beat $99 each .
the Growatt 3000 ES is designed for 250v PV so I just figure put some tape over 1/3 of 1 panel to bring voltage down then check voltage make sure under 250v.
this will give me max solar output right away with 203v VMP & 250v VOC. as most panels are closer to VOC from what I have read.
this system should run the AC & TV in full sun without battery & last at least 4-6 hours on battery alone from calculations.

Thank you for any input and suggestions.
 

Zwy

Solar Addict
Joined
Jan 3, 2021
Messages
1,050
I am a newbie I have been doing research and figuring out size of solar panels and battery I need for my RV.

My ? is with a all in 1 inverter like the one I am looking at Growatt 3000 ES it has built in mppt.
if I am using my own Daly BMS on my 48v DIY battery do I still just hook + & - to the battery input on the Growatt ???

Fuses? Circuit protection?

I am guessing set the Growatt to Lifepo4 parameters and it will push the proper voltage to the battery & my BMS will keep it in balance etc is this correct??

The GW is set under the USER setting for what parameters you set for charging and discharge limits.

any images of a all in 1 tied to a DIY battery 48v would be great.

This is what I have specked out for my system.
any recommendations would be great.
especially if you can get me to 250v PV with less then 7 panels measuring 65x39x2 each :rolleyes: things are big.
smaller panels with same voltage would be really nice. saves me space on the roof.
4qty - 60v voc or vmp panels would be the best thing I could have I think, putting me right at the 240v .

Better take cold temps into consideration as panels produce higher voltage when cold. Don't push right to the limit of the charge controller.

Back to the plan.
this is for off grid use when not hooked to shore power.
the native 12v system in RV will not be touched it will be left alone in the RV.
the plan is to have the solar system inverter as as separate power bank powering directly into 1 of the - 110v pole/legs of the RV shore power system / breaker box eliminating issues of 48v to 12v step down & still have he ability to use factory electric RV system.
this will allow me to power tv, the native12v converter and small appliances as well as 1 AC unit that pulls under 10 amps.
maybe in the future if need more capacity I will go 2p & power the 2nd 110v pole/leg in the breaker box for more air conditioning with another Growatt 3000 ES, if I can afford it as well LOL.

I am going with a 280ah or bigger lifepo4, DIY 48v battery bank Daly 150AMP BMS , 2/0 wires
Jinko panels 265watt x 7 total output 256v can't beat $99 each .

If you go 7S, you will have VOC at 270 volts for Jinko 265w panels I found specs for.

the Growatt 3000 ES is designed for 250v PV so I just figure put some tape over 1/3 of 1 panel to bring voltage down then check voltage make sure under 250v.

Doesn't quite work that way. You need to watch Amy show what happens.
this will give me max solar output right away with 203v VMP & 250v VOC. as most panels are closer to VOC from what I have read.
this system should run the AC & TV in full sun without battery & last at least 4-6 hours on battery alone from calculations.

Thank you for any input and suggestions.
 

motomarc

New Member
Joined
Feb 16, 2021
Messages
15
Fuses? Circuit protection?



The GW is set under the USER setting for what parameters you set for charging and discharge limits.



Better take cold temps into consideration as panels produce higher voltage when cold. Don't push right to the limit of the charge controller.



If you go 7S, you will have VOC at 270 volts for Jinko 265w panels I found specs for.



Doesn't quite work that way. You need to watch Amy show what happens.
Of course breakers and fuses where needed.
The 265 units I was looking at are on signature solar there 36.7 VOC & 29.8 VMP not 60v voc .
If I go 6 panels then I will be at 178 VMP & 220 VOC if this is sufficient then I will go that way. I should be just fine in cold with this.
 
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