Gas generator to backup solar

[kdwhite67]

I am new to solar, but I am extremely proficient in hooking up 110V generators (I take it that your 1000 watt generator does not provide any 220 service) to the home, including how to crank the generator automatically (if it is cranking battery equipped) when it needs to turn on (and off) and to safely integrate it into the home and still be UL 1008 complaint.

To do this safely you'll need a transfer switch. There are numerous manual ones but only one automatic one I know of for 110 volt generators. It comes in a 10 circuit https://www.apc.com/shop/us/en/products/APC-Universal-Transfer-Switch-10-Circuit-120-240V/P-UTS10BI and 6 circuit variety https://www.apc.com/shop/us/en/products/APC-Universal-Transfer-Switch-6-Circuit-120V/P-UTS6 .

I seem to recall at one point that Honda was bundling this automatic transfer switch under the own label, addition to APC selling to other dealers. Honda may still do so.

If you want the generator to start (or stop) automatically I recommend either of these: the more to do one: http://atkinsonelectronics.com/gscm-generator-start-control-module-rev-c-5-13/ or http://atkinsonelectronics.com/gscm-mini-60hz-usa-canada/.

It's pretty straightforward to start and stop a generator based on the presence or absence of either AC or DC current, the latter can also be set to a voltage threshold.

I've done what you wish to do it sounds like. If I can be of help please post back. Of course I am a hobbyist seeking to help for only good karma.

Thanks! I'm digesting all the great thoughts on this and trying to figure out all the options.... I don't need the generator to automatically start and stop. I will be starting it manually and shutting it down when the batteries are charged.

 

[kdwhite67]

AGM, good to install indoors, no need to move around. Only severe overcharging (e.g. hook up a basic battery charger and forget) will cause bulging and outgassing.
Just have batteries and inverter indoors. AGM is quite freeze resistant even at relatively low state of charge.
Main thing to get good life out of them is for them to achieve full charge (bulk, absorption, then float) which a good charge controller will do. If settings are adjustable, read manual for battery and fine-tune charge controller settings to match.
With all loads disconnected the batteries can sit all winter.
Don't let battery run down below 50% or maybe 70% depth of discharge, and recharge soon after. So turn off inverter if there isn't going to be sufficient solar charging to support it.

Quick Question.... is it safe to connect a 20a battery charger to battery while it is still connected to the solar charge controller?

 

[Hedges]

Quick Question.... is it safe to connect a 20a battery charger to battery while it is still connected to the solar charge controller?

Yes, no problem unless total charge current would be too high for battery.
What does documentation for battery say regarding max charge current?
250Ah at 0.1C would be 25A charge, at 0.2C would be 50A charge. Probably 20A plus whatever your PV produces is fine.

Make sure the charger has suitable charge profile for AGM, regulates to appropriate maximum voltage. Simple battery chargers may go too high.

 

[Arbee]

Thanks! I'm digesting all the great thoughts on this and trying to figure out all the options.... I don't need the generator to automatically start and stop. I will be starting it manually and shutting it down when the batteries are charged.

I hear this. I have another thought. If this is going to be a regular thing..this use of the generator....AND you have access to propane or natural gas, consider what I did and convert the generator to run on all 3 fuels: propane, natural gas and gasoline.

Gasoline makes for unreliability. It has a 6 month shelf life short of putting chemicals into it to slow down its decomposition as a fuel, and it can gum up carburetors. Propane and natural gas store longer, burn with less fumes, and won't gum up your carburetor.

https://www.uscarburetion.com/

Don't hesitate to ask for help.

 

[kdwhite67]

I hear this. I have another thought. If this is going to be a regular thing..this use of the generator....AND you have access to propane or natural gas, consider what I did and convert the generator to run on all 3 fuels: propane, natural gas and gasoline.

Gasoline makes for unreliability. It has a 6 month shelf life short of putting chemicals into it to slow down its decomposition as a fuel, and it can gum up carburetors. Propane and natural gas store longer, burn with less fumes, and won't gum up your carburetor.

https://www.uscarburetion.com/

Don't hesitate to ask for help.

Thanks for the info!