Generators, voltage quality, and "sensitive electronics"

[Ken45101]

I have had the Honda EU2000i and now the EU3000i. Zero problems with electronics and they are quiet!

I also have a tractor PTO generator (15k) for longer term outages. I doin a short test run with it, no problems. This is big enough, and mobile on the tractor, I could take it and the welder or plasma cutter anywhere on the farm if needed.

 

[mjonesnh]

I have a Wen 56203i 2000 watt inverter generator that starts a Kobalt 1.5 hp air compressor I keep in the truck for farm use. Not sure how this load compares to starting a well pump. but the amp rating is 12.1 amps and compressor kicks out at 155 psi and back on at 120psi. Generator rpm's drop very little re-starting compressor at 120psi

 

[ponytug]

I have a Wen 56203i 2000 watt inverter generator that starts a Kobalt 1.5 hp air compressor I keep in the truck for farm use. Not sure how this load compares to starting a well pump. but the amp rating is 12.1 amps and compressor kicks out at 155 psi and back on at 120psi. Generator rpm's drop very little re-starting compressor at 120psi

Compressors are designed to have relief valves that drain the air pressure out of the compressor to tank line, so compressors get to start against no load. The relief makes a big, ok huge, difference in starting loads.

Glad that the setup works well for you,

All the best, Peter

 

[Cub 7275]

The 8 house neighborhood has been on generators since Monday, 5 portables and 3 automatic stationary units. We all run our well pumps, TVs, computers, etc and no one has yet mentioned having any problems with electronic failures. If we are lucky, power will be restored by 10 pm tonight.

We've used a few rental generators, then bought a Craftsman 6300 generator in 2005 and now have a Ridgid 5700 that has cleaner power. Installing a transfer switch to power most of the house was the best thing ever. We power a ½ hp well pump 63’ deep, refrigerator, sump pump, gas furnace, microwave, washer and gas dryer, dishwasher, most interior lights, TVs, game consoles, computers, router, basically everything but the AC, electric hot water heater, electric ovens and stove top. Of course we do not try to run everything at once.

To the OP’s question, thinking way back in 2006 or so we did have a computer power supply failure, but there is no way to know if that was related to the Craftsman generator or not. The Ridgid generator has some stupid vapor recovery crap that caused it to pull too much vacuum on the fuel tank and stall. We dodged a few bullets because when it stalls under load bad things can happen electrically. I reworked the tank venting and it has been trouble free since. So 17+ years of generator operation many times a year for up to 2 weeks at a time and no confirmed electronic failures due to the generators. The other neighbors have been dealing with generators far longer as they said the power reliability was much worse before we moved in

Those of us with portables are discussing a group buy for whole house gen sets. This thread is timely because it reminds us to consider the quality of the generator output. I’d like to see a graph of that “pure sine wave” inverter output to see just how “pure” it is or if it is just marketing hype.

Given the likely increased disruptions to our local grid from the coming EV boondoggle, I think its time for us to get serious about a permanent automatic gen set. So now what fuel to select and if sizing the generator for the entire house is enough or to include extra for an EV, or more likely PHEVs, etc.

Can you install a soft starter on a well pump?

They make VFDs for well pumps, so yes, that could be used as a soft start. That said, I would be concerned about feeding a VFD with crappy generator power.

 

[Will S]

I have had a 6800W Mitsubishi generator and 9 circuit manual transfer panel, and it not only ran the 1HP well pump without breaking a sweat, but also furnace, and some lights and TV.


The only problem (not with it, but with me), was deciding how much longer to wait before dragging it outside, most likely during a storm, then connecting it with the 30A feed cable to the outside gen power inlet, then starting it (has electric start but that adds another thing to maintain). So manual start always started on 1st pull, then go to gen transfer panel and select which of the 9 circuits I want power to...

So, about a years or so ago, I installed a whole house gen with auto-transfer, removed the gen manual transfer panel; I no longer have any use for it. (I should probably put in on some classifieds).

But back to the point; it always ran my well pump, fridge, freezer, and more, just fine.

 

[ponytug]

The 8 house neighborhood has been on generators since Monday, 5 portables and 3 automatic stationary units. We all run our well pumps, TVs, computers, etc and no one has yet mentioned having any problems with electronic failures. If we are lucky, power will be restored by 10 pm tonight.

We've used a few rental generators, then bought a Craftsman 6300 generator in 2005 and now have a Ridgid 5700 that has cleaner power. Installing a transfer switch to power most of the house was the best thing ever. We power a ½ hp well pump 63’ deep, refrigerator, sump pump, gas furnace, microwave, washer and gas dryer, dishwasher, most interior lights, TVs, game consoles, computers, router, basically everything but the AC, electric hot water heater, electric ovens and stove top. Of course we do not try to run everything at once.

To the OP’s question, thinking way back in 2006 or so we did have a computer power supply failure, but there is no way to know if that was related to the Craftsman generator or not. The Ridgid generator has some stupid vapor recovery crap that caused it to pull too much vacuum on the fuel tank and stall. We dodged a few bullets because when it stalls under load bad things can happen electrically. I reworked the tank venting and it has been trouble free since. So 17+ years of generator operation many times a year for up to 2 weeks at a time and no confirmed electronic failures due to the generators. The other neighbors have been dealing with generators far longer as they said the power reliability was much worse before we moved in

Those of us with portables are discussing a group buy for whole house gen sets. This thread is timely because it reminds us to consider the quality of the generator output. I’d like to see a graph of that “pure sine wave” inverter output to see just how “pure” it is or if it is just marketing hype.

Given the likely increased disruptions to our local grid from the coming EV boondoggle, I think its time for us to get serious about a permanent automatic gen set. So now what fuel to select and if sizing the generator for the entire house is enough or to include extra for an EV, or more likely PHEVs, etc.


They make VFDs for well pumps, so yes, that could be used as a soft start. That said, I would be concerned about feeding a VFD with crappy generator power.

On your group buy, look at the THD number. That is the amount of energy not at 60Hz, I.e. noise. Measuring THD yourself requires some pricey equipment, but a oscilloscope will give you an idea of how clean things are.

I'm generally a fan of VFDs. I do think that there is a specific issue with VFDs on well pumps. Well pump VFDs have long supply wires between the VFD and the pump. The long distance between the VFD and the motor is a great recipe for strange harmonics and motor burnout. In my opinion, you want a high quality VFD for a well pump, with reactors (filters) on the input and the out from the VFD. The reactors can cost almost as much as the VFD, and are often omitted in other types of VFD installations, but I think for wells, they are quite important.

All the best,

Peter

 

[newbury]

My question about soft starters for well pumps was brought about because of all the comments about needing a much larger generator to get the well pump started than what it needed once running.

 

[Larry Caldwell]

Good info here:

"In a traditional generator, the power produced by the alternator is fed (more or less) straight to the control panel. It may go through a voltage regulator or other protective devices, but the power is not necessarily “cleaned up”. Therefore, the power produced by a traditional generator has a higher total harmonic distortion (THD) than the power produced by an inverter generator. THD is a measure of how clean the power is – more on that in a moment.

An inverter generator works differently. The alternating current (AC) power produced by the alternator is sent to a rectifier, which is a device that converts the AC power to direct current (DC). This DC power is then inverted back to AC power by the computer inside the generator before it is sent to the control panel. This is where the name “inverter” comes from. Because the power to the control panel is controlled by the computer, inverter generators offer much lower THD than standard generators. THD is an important consideration when powering sensitive devices, like smartphones, tablets, computers, and televisions. These devices expect “clean” power (power that has low THD, like the wall power in your home), and can be damaged if they receive high-THD power. All WEN inverter generators use pure-sine-wave inverters, and as such, limit THD to under 1% in most cases. Traditional generators can produce THD as high as 25% in some cases."

How Do Inverter Generators Work?

NOTE: If you're looking for a more basic explanation about the benefits of inverter generators, check out our post explaining their advantages here. If you’re in the market for a new generator, you’ve probably noticed by now that there are many different types of generator – standby, portable...

wenproducts.com

Tanking (solid state) power supplies are mostly oblivious to frequency or voltage variations. Harmonics are high frequency harmonic noise and can be filtered cheaply with an autotransformer/line stabilizer that chokes the harmonics while letting low 60 hz. frequency through. For me, the big advantage of an inverter generator is that the motor can idle down under low load conditions, saving both wear and tear and fuel.

 

[not2old]

I don't know how big my well pump is but I picked my generator as a compromise between large enough to provide 240v to my well pump and small enough to use camping. 5000/6500 runs the pump fine. When I operate the tv, satellite box, a couple of lights and the microwave, I tell the boss not to turn on the water when the microwave is running. Works fine for us.

 

[bigtiller]

A well pump question from a novice. Does anyone manufacture a well pump with a soft start motor?

 

[Agvg]

A well pump question from a novice. Does anyone manufacture a well pump with a soft start motor?

Submersible pumps are usually soft start to reduse the twisting force on the plastic hose.

If it's not you should be able to buy one from an electrician.

 

[ultrarunner]

Lots of generators bought in a rush when utility started cutting power due to fire danger.

My guess is 95% had no clue and I have helped a few when the 1100W generator didn’t do what they thought it should.

The next issue is living with the sound… especially when the whole neighborhood is mowing their lawns at midnight is what it sounds like.

Utility just put out a notice of incentive to purchase specified generators and get a $300 rebate and then be eligible for a free meter tie in which incorporates the disconnect.

Time will tell… would love to have the meter tie in but don’t need another generator.

 

[ponytug]

Lots of generators bought in a rush when utility started cutting power due to fire danger.

My guess is 95% had no clue and I have helped a few when the 1100W generator didn’t do what they thought it should.

The next issue is living with the sound… especially when the whole neighborhood is mowing their lawns at midnight is what it sounds like.

Utility just put out a notice of incentive to purchase specified generators and get a $300 rebate and then be eligible for a free meter tie in which incorporates the disconnect.

Time will tell… would love to have the meter tie in but don’t need another generator.

Buy the generator, get the meter tie, and sell the generator? I had similar thoughts.

All the best,

Peter

 

[ultrarunner]

Buy the generator, get the meter tie, and sell the generator? I had similar thoughts.

All the best,

Peter

Me too… last I checked that type of tie in was not PGE approved per the manufacturer’s website.

It would be nothin to the install at Moms but I have not thought through what complications if any adding the tie in with existing solar

 

[Larry Caldwell]

Me too… last I checked that type of tie in was not PGE approved per the manufacturer’s website.

It would be nothin to the install at Moms but I have not thought through what complications if any adding the tie in with existing solar

Good question. A meter transfer would probably heat up the solar inverter, which could end with the solar running the generator, leading to system damage. You may have to shut off the solar inverter separately. No problem as long as it's dark out.

 

[ponytug]

Me too… last I checked that type of tie in was not PGE approved per the manufacturer’s website.

It would be nothin to the install at Moms but I have not thought through what complications if any adding the tie in with existing solar

Good question. A meter transfer would probably heat up the solar inverter, which could end with the solar running the generator, leading to system damage. You may have to shut off the solar inverter separately. No problem as long as it's dark out.

Yes, you need to shut off solar when in a generator for the health of both. Both "thinkl that they have control over supply when in fact it is shared, and neither can function as an energy sink.

All the best,

Peter

 

[ultrarunner]

Almost required a three-way switch to be fool proof?

 

[Larry Caldwell]

Almost required a three-way switch to be fool proof?

"A fool of sufficient magnitude can be found to overcome any fool proof system." - Edward Teller

 

[ponytug]

Almost required a three-way switch to be fool proof?

If I were wiring it up, I would put the transfer switch ahead of the house, but beyond the solar. Then you only need one switch, although two load panels.

Philosophically, I am with @Larry Caldwell and Edward Teller, though the NEC tries really hard.

All the best,

Peter