UPS that can work with portable generator?

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atarione

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So on the upside we are some distance from the wild fires in LA (not that far but we are ok for now). Lost power for several days.
Have a Honda 2200i generator which i was using to power fridge and some lights and charge phones.etc.

My (limited) understand is that I would need a different "double conversion / Generator mode" capable UPS in order to run my computer(s) from a generator? So far what I have found on amazon listing this capability is quite pricey.

Does anyone here have any experience w/ this in a home setting ideally doing so at something less than enterprise IT pricing?

Would I need a bigger generator to power fridge and PC / Monitor at same time (plus few other thing lamp phone chargers..etc?)

My current UPS is a APC Back-UPS 700VA which if I understand would be unsuitable for operation w/ my generator.. didn't want to damage my computer and had other things to deal with so didn't try it. Due to wanting to be sure it would not cause damage before attempting?
 
So, that generator is rated for 15a@120v. I wouldn't normally share a 15a circuit between a fridge and a computer, because when the fridge starts its compressor, it can be a big jump in load and if the computer is a big load too, it might trip the breaker. On the generator, you'll see a big dip in output voltage when the compressor kicks on, and a jump when it kicks off.

As for running your computer on your generator. With your UPS, if the input power looks good enough, it's connected to the output more or less directly. Small generators tend to have pretty nasty power, so sometimes the UPS will rapidly change over to and from the battery... You're not going to have a good time if that happens. You might not like feeding your computer with generator power, but the power supply does a lot of slicing and dicing with the power anyway, so it's probably not awful.
 
Uhhh what.

You can use any generator for your UPS that can provide enough output to recharge your UPS faster than you can empty it.
 
auntjemima said:
Uhhh what.

You can use any generator for your UPS that can provide enough output to recharge your UPS faster than you can empty it.
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If the output from the generator is outside the range of what the UPS considers good, it likely won't charge from it. If it frequently switches, it's likely counter productive as well. With a small generator like that, I'd probably try it and see if the UPS likes the power if the only the ups is connected and the computer is off and scale up from there. But probably not run the computer and the fridge at the same time. Probably don't need the fridge and the computer all day or you'd have a bigger generator. :p
 
toast0 said:
If the output from the generator is outside the range of what the UPS considers good, it likely won't charge from it. If it frequently switches, it's likely counter productive as well. With a small generator like that, I'd probably try it and see if the UPS likes the power if the only the ups is connected and the computer is off and scale up from there. But probably not run the computer and the fridge at the same time. Probably don't need the fridge and the computer all day or you'd have a bigger generator. :p
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A small generator like that is perfectly fine. A generator SHOULD output 120v @60hz. If it doesn't, adjust the throttle until it does. We run highly sensitive equipment all the time on generator power. As long as your UPS can handle it, and your generator is properly adjusted, it will be fine.
 
We used to occasionally use generators for live recording, sound re-enforcement, etc. What I found is some s#!tty generators actually put out 120VAC, 60Hz.....SQUARE WAVE. Not so good. Most generators these days do a much better job producing decent sine wave AC. So, capacity aside, it really depends on the generator and the UPS. Some UPS's will see the s#!tty power coming in and not charge nor draw power from the mains. Honestly I don't know how common this is, but it's for sure something to be aware of. If you've got the tools, you can look at the generator power on an oscilloscope and get an idea what you're dealing with. Note most scope probes are only good for 20V or something like that, so they are not usable for 120VAC......yes, I found out the [H]ard way......once.....:D
 
BlindedByScience said:
We used to occasionally use generators for live recording, sound re-enforcement, etc. What I found is some s#!tty generators actually put out 120VAC, 60Hz.....SQUARE WAVE. Not so good. Most generators these days do a much better job producing decent sine wave AC. So, capacity aside, it really depends on the generator and the UPS. Some UPS's will see the s#!tty power coming in and not charge nor draw power from the mains. Honestly I don't know how common this is, but it's for sure something to be aware of. If you've got the tools, you can look at the generator power on an oscilloscope and get an idea what you're dealing with. Note most scope probes are only good for 20V or something like that, so they are not usable for 120VAC......yes, I found out the [H]ard way......once.....:D
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Maybe I will test (plug the UPS into the generator and see if it freaks out or not... I am concerned about the dirty power that generators produce messing up my computer... but I guess the UPS would protect it, assuming the UPS can deal with the input from the generator?

If got no means currently to test the signal from the generator to be honest... hmmm maybe I will ask one of the engineers I work with if they can take a look at it, at some point.
 
auntjemima said:
Uhhh what.

You can use any generator for your UPS that can provide enough output to recharge your UPS faster than you can empty it.
Click to expand...
It’s not at all that simple. Generators are NOTORIOUS for putting out shitty dirty power that’s barely within limits of what’s considered standard. Electronics hate dirty power, including any but the most basic UPS units. They don’t like choppy square wave power most generators that are consumer grade put out. So no, not that simple.

Some generators have great power smoothing circuits that jive with electronics. That’s what would be needed for a decent UPS. A UPS can condition some of the dirty power, but no where near the amount of dirty power generators can output.
 
Dreamerbydesign said:
It’s not at all that simple. Generators are NOTORIOUS for putting out shitty dirty power that’s barely within limits of what’s considered standard. Electronics hate dirty power, including any but the most basic UPS units. They don’t like choppy square wave power most generators that are consumer grade put out. So no, not that simple.

Some generators have great power smoothing circuits that jive with electronics. That’s what would be needed for a decent UPS. A UPS can condition some of the dirty power, but no where near the amount of dirty power generators can output.
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Guess I've been pampered by some of the best UPSs then.
 
auntjemima said:
A small generator like that is perfectly fine. A generator SHOULD output 120v @60hz. If it doesn't, adjust the throttle until it does. We run highly sensitive equipment all the time on generator power. As long as your UPS can handle it, and your generator is properly adjusted, it will be fine.
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The Honda EU2200i is an inverter generator, which means it should output a pure sine wave output. In fact, the Honda are actually known for being the best at this, with cheap inverter generators known to cause issues. Lots of info in camping forums and trying to use generators with Ecoflow and Jackery batteries. They need pure sine as well.

A lot of camping/RV 4000+ watt generators are not inverter generators and those will cause issues with electronics, especially the open frame ones. Not applicable here though, the biggest issue will be output. If the refrigerator kicks on and overloads the generator, it will cut power temporarily before ramping back up and providing power again, at which point the refrigerator and UPS will try to draw power and overload it again, creating a nonstop cycle. To run off one generator, OP would have to be mindful of unplugging the UPS each time the refrigerator kicks on.
 
Dreamerbydesign said:
Perhaps you have. You’ve tested many on generators?
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Let's just say that nearly all of my 20 years of experience has been on generator power. From Deutz to Subaru to Honda. It's generator -> UPS -> devices. The devices get clean power from the UPS. As long as it can handle the load and the UPS is happy enough with the generator, it will be fine. The purpose of the UPS is to provide a clean 120/60, even if it's recharging source is a bit wonky. If he's at the limits of his UPS, and the generator cannot provide a clean enough recharge, he may discharge faster than the UPS can be replenished, but otherwise he should be fine.

I mean, consider what a UPS is for.. power drops. We use them to maintain sensitive equipment in case the power goes out, shore or gen power.

Lower voltage or lack of 60hz (that can be adjusted for) on a gen is better than a complete power drop, yet any reasonable UPS can handle that situation (as that's it's job).

I've worked on camp wiring for camps with hundreds of people. That includes living quarters, labs, kitchens, washing facilities, computer labs, etc. Gen power from that Honda should be more than enough to use a PC and fridge. The gen may drop output slightly when the fridge kicks in, sure, but all I would expect to see from the UPS would be a warning that the load is too much, and then quickly be resolved. Spikes are fine, as long as the regular load is below the generator and UPSs capability.
 
Tsumi said:
The Honda EU2200i is an inverter generator, which means it should output a pure sine wave output. In fact, the Honda are actually known for being the best at this, with cheap inverter generators known to cause issues. Lots of info in camping forums and trying to use generators with Ecoflow and Jackery batteries. They need pure sine as well.

A lot of camping/RV 4000+ watt generators are not inverter generators and those will cause issues with electronics, especially the open frame ones. Not applicable here though, the biggest issue will be output. If the refrigerator kicks on and overloads the generator, it will cut power temporarily before ramping back up and providing power again, at which point the refrigerator and UPS will try to draw power and overload it again, creating a nonstop cycle. To run off one generator, OP would have to be mindful of unplugging the UPS each time the refrigerator kicks on.
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More recent 2200i models can be paralleled together to do more power with a cheap kit. I recommend the eu7000is though because it's 6.something kw sustained and fuel injected as well as very good inverter tech. We have 2 of them to start our air conditioners and stuff in parallel mode if we only need one at a time and to run the kitchen and computers.
 
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