Maximize power from a portable generator

I had probably the same 3500 champion for years. It's a great open frame non-inverter genset. Thing is it's 3500 watt peak output and it's a 120/240 generator so each 120 volt leg can only product 1750 peak. Since he probably had some other stuff on that microwave probably used up about all that remained on the one leg. My current home microwave has a tag inside that says it uses 1580 watts.

Then yes, motors run noisy on the relatively dirty power. It's not the Hertz (frequency/RPM/governor) that causes trouble but the actual THD Total Harmonic Distortion of the output. It doesn't make a nice sine wave and motors feel the choppiness and make noise, lights flicker.

Champion has since done a weird thing on their new stuff. They advertise a 3500 watt genset but that's now running watts with a much higher peak rating. So that's cool.
3500W Generator with CO Shield® - 201286 - Champion Power Equipment

I've gone to 120 volt inverter gensets for baseload and then a big hoss fuel hog 240 generator for the well, water heater, oven/range, and even heat pump. All backfed through the house panel and an interlock. Inverter power is so perfect. Better than utility power. A 3000 watt inverter that can put out all 3000 watts on one phase is a pretty great size for a house with wood heat.

And yes, always dual fuel if you can.

 

Watts to amps is just math. 3500 watts at 120 volts is 29.2 amps. If a device plugs into a 20 amp outlet then a 3500 watt generator will run it unless it's a 120/240 genset with only 1750 going to each leg. Then that's 14.6 amps and might not run big loads. Don't obsess over amps.

 

I have same open frame champion generator old 1985 I know math but I also know what didnt work when I needed it too. Could have been windings magnets yes but it would not push 20a electric staple gun
I also have a proof from aeronautical engineer that says bumblebee can’t fly They do

A 1930 bi plane doesnt have power to weight ratio to do a loop in air but my grandfather lost his pilot license in 1931 for 60 days cause he did it … kill power at top of ascent use prop for neg air pressure adjust flaps heavy part of plane engine falls first

in short not trying to argue but it would not operate plug in hand tools, when needing to close hole in envelope of house in snow storm? do you say mathematics say it should push this load or grab bigger generator turn it on and get it done. I chose later

 

I’m saying the reason your generator couldn’t run your tool has nothing to do with whether you used watts or amps. Also nothing to do with planes or bees.

 

Highbeam you are right
At a contractors; generator to plug in panel to extension cord easy to do simple. It works

morningwood Get bigger than what need. I quote my wife “candles in a bathroom are after 3 days is NO LONGER ROMANTIC “, I am still happily married


In HOUSE world
wife getting ready for work; 12 yo daughter are getting ready school
It’s 5am it’s dark you’re running a house. It’s on breakers and circuits coffee pots, toasters that’s all fine mathematically.
Do you know where each line goes? what is on what circuit? What about unplanned draw
Well pump kicks on, refrigerator cycles, freezer, flip on light switch?
how many times it popped a breaker BY plugging in of a charger

Explain to girls; daughter 12? Wife and MIL who English is not first language

Who don’t know electricity and don’t want to know about surge, , continuously draw, cycles, ohms watts

I found IME AMPS is the BOSS

Instapot Is 8-10 Amps on 20a circuit
easy to explain teach and if go past 29.2 or tell them 28


Moms starts complaining and dad is swearing in his boxer and a flannel shirt with a flashlight at 5 am in snow Storm!!
The math don’t matter MAKE IT WORK


Edited to Add
In my opinion and I think Highbeam will agree
I respect his opinion and I am using analogies and metaphors to make my point and he is highly intelligent and knows that. and he is using math and quick quips to make his points WHICH are correct
There are no hard feelings

 

I'll get some pictures later of the generator. It was an el cheapo Champion open frame RV generator from TSC when I bought it 10+ years ago. You get what you pay for sometimes.

You are spot on why the microwave wasn't happy after doing some investigation. I'm not sure why, but the electrician put the majority of the 120V breakers on the left side of the panel and most of the 240v breakers are on the right. I've always been told that they should be balanced as best as possible.

My microwave is 1700 watts input (14.166 amps) and 1000 watts output.

 

The 240v loads don’t matter; they are balanced automatically. As you go down the panel, regardless of left or right, each 120v slot is an alternating leg. Having all the 120v on one side and 240v on the other does not by itself affect load balance. What matters is what buss bars the high load 120v breakers happen to fall on. Sometimes it may be useful to swap adjacent 120v breakers to balance the 120v loads better.

* the above is for a typical single phase panel*

 

The electrician probably did the right thing. The panel isn't divided in half left to right. Every other slot is on the same leg of 120. That's why a 240 double pole breaker only has to bridge two adjacent slots to get 240. So a stack of 120 volt, single pole, breakers on one side of the panel is the correct way to evenly distribute the demand to both legs of 120. You have a nice big thirsty microwave with lots of oomph at 1700 watts. That would wipe out, or at least severely imbalance that one side of the 3500 watt generator's output. Another sorta weird thing about most 120/240 generators is that the voltage regulation is based on only one of the legs, they assume an evenly loaded generator. So loading up the wrong leg can cause a big voltage drop. Of course, the solution for all things is to get a bigger genset. They also make 240 inverter gensets now too for better power quality plus less noise and fuel consumption but more cost.

 

I'm not sure I understand most of that post but here's another quick quip for you, you can totally get the right answer using amps instead of watts if that helps you. It's just not wrong to use watts instead. Both get you the same answer.

Using smaller generators for household power requires some effort and planning to avoid overloads and possible damage. Like running a cat stove, it becomes much easier with experience.

 

That's the route I'm heavily leaning towards.

Thanks for the explanation Highbeam and Gearclash

 

Why I respect you sir! I do have disabilities and written concise explanations are a challenge for me math and numbers easy. I admire your ability to be clear and concise

Was trying to share my experience living on generators 24/7 for 3 weeks continuously after natural disaster which caused house fire
Using what could be obtained. Regular generator not designed for long term continuous use probably bad example. In life I have found unless researching to purchase, most people don’t care they just want it to work

 

Watts is (amps x volts). Most time we only bother with amps because we know what the voltage is so all we care about is how many amps we can shove through a wire before something goes ffffffffffffftttt.

 

Watts/amps/volts...if you know any 2, math gives you the third.

 

Here's the only one I ever learned. Watts was just an add on/after thought.

 

What generator not to buy if you want clean power. The frequency was jumping from 61ishHz all the way up to 64Hz. Plugged an old school fluorescent work light into it, it didn't change. Plugged the Kill A Watt meter into a socket in my house, it's a pretty consistent 60Hz.

 

that’s a very good clone of a very good engine. If it was surging, not holding a steady hertz, it is because the carburetor was gunked up.

Any generator with a gasoline carburetor will start surging as the carb plugs up. It’s pretty common since generators often sit unused for long periods.

 

Exactly what I was thinking (among possibilities) when I posted this earlier

 

Absolutely, as I stated math is easy for me. Why I said “amps is the Boss” I have been thinking about last few days.. hey it’s snowing and wet sloppy outside.

it’s my life experience, it has altered my perception! Landlord renting low income housing apartments.
Generally 2 separate circuits for kitchen countertops standard 20 amp. Received many complaints about popping a breaker. Everyone posting on this thread could walk in look at counters and see why..
Too many times an hour of my life was spent moving toaster or microwave plug from 1 circuit to another to prevent

some people aren’t math people and common sense is rare in segments of population.

 

Our whole kitchen is on (2) 15 amp circuits, other than the stove/oven and lights (and maybe the fridge...can't recall right now)
Can't use the toaster oven and the microwave at the same time (same circuit) Sounds like a real pain, but not that big of a deal for us, as long as it's remembered...the trip to the basement to reset helps you remember next time though...

 

brenndatomu my home is a 5 story house, 3 car garage and 30x40 horse barn. Before the whole meter socket caught fire fiasco was a 100 amp; 20 circuit system. That led to the PM started by Backwoods Savage

I bought house as is out of foreclosure; one reason I could afford it in 2003 was; housing regulations here required many homes to have 1 or 2 empty circuits. House at purchase had none, it was noted in appraisal for bank and a glitch on my financing.
resolved because I had once helped a friend pass journeyman (step below master electrician) exam; he had a dyslexia couldn’t do math. Since I had taken exam even though I didn’t have hours on job, I was uncertified but name was on the list..

Morale of story; helping people with a hand up not hand outs is a good thing; and my home is my refuge and helped convinced my beautiful bride to marry me, but that is a long story lol