Growatt 6k inverter (want to use generator as "grid")

[Jonathan3900]

I have a Growatt 6k inverter. I also have 6-350 watt panels, and 2 Big Battery Husky 5.3kw batteries. I live in Ohio, and we get a lot of snow sometimes. I want to wire a propane generator into the Growatt and use is as the "grid" when the batteries get low. Is there a way to have the inverter to trigger a generator to start and charge the batteries, and once they are charged, to shut off the generator? Thanks for any help.

 

[BartHenry]

if its a 2 wire generator then you can use the dry contact on the inverter. use C and NO.

 

[Jonathan3900]

if its a 2 wire generator then you can use the dry contact on the inverter. use C and NO.

Thank you. I will tell my electrician. I was looking at an AGS unit. Might be another option.

 

[Vigo]

Not sure on the 6k but my spf5000es it is settings #12 and #13 which would determine when the generator starts and turns off.

 

[Jonathan3900]

Not sure on the 6k but my spf5000es it is settings #12 and #13 which would determine when the generator starts and turns off.

Thank you very much. I appreciate the info. I think it does on mine as well. I think this should be a fairly easy thing to accomplish, but I am not sure on what generator would be best. Question number two?

 

[Vigo]

BartHenry touched on that.. the way that generators can be remotely started varies, and i dont know much about that. I believe some you can feed a simple on/off signal to (which is what the dry contacts on the growatt provide) and some you need to have some kind of 'module' in between to manage it.

As far as sizing the generator, on my Growatt and possibly yours you can set a limit on how much battery charging current can come from the ac input, but you can't put an overall limit on what it pulls because it will pull those charging watts PLUS whatever watts your loads are. So whatever your max loads are in Watts, plus however many watts of charging you want to do while doing that, plus a huge fudge factor because generators have problems with 'surge' loads, is how big of a generator you should have. I have seen the most simplistic advice be to run a generator twice the size of your inverter. I doubt you want to run a 12kw generator, so the real solution is somewhere in between 6kw and 12kw based on how 'careful' you are ok with being, while on generator power. If you are REALLY careful about what loads you turn on and off, you can get away with a <6kw generator.

 

[Jonathan3900]

if its a 2 wire generator then you can use the dry contact on the inverter. use C and NO.

Thanks for the info. I have contacted a few generator vendors, as well as, my electrician. Everyone has the same question. If I get a 2-wire generator, using the C and NO off of the inverter will start and stop the generator? Or does there need to be anything in between? Sorry for the question, but I can't figure it out. Thank you for any help.

 

[schmism]

Give Ian a shout over on watts247.

My understanding was that the dry contact goes low (short to ground) and will stay that way till the triggering condition (low battery) is resolved.

note these "triggering" conditions are configurable in the menu for the inverter (for my 3000lvm its program 24) You can find more info in the instruction manual for your unit.

 

[Daveyclimber]

I haven't had any luck getting my dry contacts to fire up my generator except for 1 time. A bit of a disappointment.

 

[markaubin]

I have a similar question regarding my Growatt 12KW unit. I'm currently using a HF Predator 9500 inverter generator which works fine but is entirely manual and uses gasoline.

Looking for a propane home standby generator in the range of 8KW - 15KW that can auto start/stop with the Growatt. Currently I'm considering Generac, Cummins and Champion.

So has anybody here done this successfully yet?

 

[Jonathan3900]

I have a similar question regarding my Growatt 12KW unit. I'm currently using a HF Predator 9500 inverter generator which works fine but is entirely manual and uses gasoline.

Looking for a propane home standby generator in the range of 8KW - 15KW that can auto start/stop with the Growatt. Currently I'm considering Generac, Cummins and Champion.

So has anybody here done this successfully yet?

Thanks for inquiring. Question. What is in between your Growatt Inverter and your generator? Or is it hard wired directly into the generator from the inverter? I am looking to set mine up, but have been told a few different answers.

 

[lotsofyoda]

I haven't had any luck getting my dry contacts to fire up my generator except for 1 time. A bit of a disappointment.

I’ve tried as well. Apparently the dry contact isn’t reliable on the growatts. In fact, Signature solar won’t support the dry contact. I’ve been told to use a shunt in the system instead. I’m buying a Victron shunt for this and putting it in. It’s expensive but apparently the gold standard to monitor SOC and allowing you to for sure start and stop generators at defined battery SOC levels. You want a Victeon shunt that also has the relays. Looking forward to solving the same Problem with that.

 

[markaubin]

Thanks for inquiring. Question. What is in between your Growatt Inverter and your generator? Or is it hard wired directly into the generator from the inverter? I am looking to set mine up, but have been told a few different answers.

Hardwired with "10/3 with ground Romex" directly from the Growatt AC input to a box on the side of the house that has a 30A plug "L-14-30" that I can connect my Predator Generator into. The Growatt 12KW has breakers for this AC input so no need for extra breakers.