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240 volt split phase backup generator recommendation

byteharmony

Sunny side up please.
Joined
Jul 29, 2022
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233
Location
Milwaukee
Getting a sol ark 15k

It only takes a 240v split phase generator input for backup power.

I'd like a recommendation on a low cost auto start generator.

Gas only okay. Natural gas added plus. No propane.

Thx in advance!
 
Don't know about sol-ark, but my Outback inverter/charger won't accept power from a non-inverter generator. They don't hold the frequency close enough for the charger to use it.
 
I'd like a recommendation on a low cost auto start generator.

Gas only okay. Natural gas added plus. No propane.
Gas only would be uncommon for an autostart. Plenty of natural gas auto start generators to choose from and they start at ~$2k for a 7.5kW and go up from there. However I think that 7.5kW is on the small side for the Sol-Ark 15k to be able to charge your batteries back up and still have room to run your house loads (or vise versa).

Here's a place I've sent a few customers to lately. Electric Generators Direct I'm still waiting to on feedback as to how the purchase goes.
 
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Don't know about sol-ark, but my Outback inverter/charger won't accept power from a non-inverter generator. They don't hold the frequency close enough for the charger to use it.
@tigerwillow1 Will the Outback (assume Radian) accept 120v or just 240v split phase. I have a great little 4500w dual fuel inverter that I would use to charge batteries, if needed.
 
One thing to look at is the settings in the inverter/charger is the input frequency. MagnaSine, and Schneider and many others do have an adjustable input frequency range that the charger will tolerate. My MagnaSine does have a very wide range and can be set wider than the factory setting of 58-64 hz. Set the range wider...say 52-68 hz. This will allow the charger to allow for “generator stumble” where the generator will drop in speed/frequency when a load is applied.

A second option is to use an auxillary charger such as an Iota which is “switch mode”. These do not care about frequency as much as a solar inverter/charger. The bad of this approach is that these (Iota type chargers) are not “power factor corrected”, requiring a larger generator to provide the charging power.

Im using a Onan RV generator which has a far larger rotating mass than most lightweight generators as a result has no problem with sudden loads applied

The MagnaSine does have a charge ramp up time on charge, unlike some units which go from zero to max in a few seconds. This allows the generator to adjust for the loading. All the Schneider units that I have seen also have this feature.
 
Don't know about sol-ark, but my Outback inverter/charger won't accept power from a non-inverter generator. They don't hold the frequency close enough for the charger to use it.
Look into the settings for your Outback, they do have adjustable frequency range to account for “generator stumble”
I have experience with only the older cast aluminum units and I know that is available for them. I have never serviced a Radian on a portable generator.
 
@tigerwillow1 Will the Outback (assume Radian) accept 120v or just 240v split phase. I have a great little 4500w dual fuel inverter that I would use to charge batteries, if needed.
My Outback inverter is an older 120 volt version so split phase is not applicable. The only input frequency spec I found quickly was for the european version, 45 to 55 Hz., so I'd guess it's 55 to 65 for the north american version. Besides the exact frequency I'm assuming stability has to be fairly good because of the H-bridge having to switch in concert with the AC input. My main source of info on this is a forum discussion years ago where an outback rep said the charger won't accept AC from a non-inverter generator and specifically recommended the honda eu series. I want to be careful to say this "might" be an issue with your inverter, not that it will be.
 
All I need is about 1500 watts. A mostly imbalanced load of 8 Amps on one 120v leg, the other is pretty idle. I assume the SOL ARK would balance the load on the 240 generator and use the extra power to charge the batteries. Once the sun comes up the 50+ solar panels should cause the Sol Ark 15k to switch to solar to charge the battery and turn the generator off.


This looks too good to be true, 7500 watts, $830 and it has the electric start which I hope is compatible w/ the sol ark on off controls. With a 6 gallon gas tank I think I'd be good to just burn the gas every 6 months to keep it fresh (selling the power of course ;). W/ a 6 gal tank in the event of a problem I may only need to fill it once a day?

I can use the Sol Ark to control how much load the generator gets when the built in chargers are sucking power. I assume I just crank it up and set it for just before the engine throttles up. That way if my load in the house increases it can spin up the generator to produce more power.

I was thinking of just getting a battery charger for my current 120v 2500 watt generator or Auto Transformer to make 240v out of 120v but at $830 I think the cost of that stuff and the loss of auto power generation start and stop would make it a poor solution in comparison.

Thoughts?
 
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