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when generator is overloaded

am attempting to size a generator and have a couple stupid questions.
assume a generator wired via manual or automatic transfer switch, nominally providing about 3-5 kilowatts of power, about 22-24 amps
apart from an overload shutting down a generator, what else occurs, typically in such a situation? does it cause home appliances to "burn" or do these typically just shut off similar to what would happen when a power utility has what is called a "brown out" or low voltage situation? sometimes our local power utility has multiple back-to-back low voltage events, causing appliances to stop-start-stop
how does a "brown out" differ from a generator overload caused low voltage shut down, aside from the fact that the generator of course will turn off and the power outage becomes a "black out".
does a generator experience permanent harm from an overload, assume it's not repeated

when generator is overloaded

"Mark L." wrote in message

am attempting to size a generator and have a couple stupid questions.

As you have already figured out, size matters. That said, especially in these days of expensive fuel, bigger is not necessarily better. You must figure out what your load is and size your generator accordingly. (Or figure out what your generator can handle and size your load accordingly)

apart from an overload shutting down a generator...

Many/most generators do not have a true overload shutdown. That can be a real problem if you don't manage your load.

what else occurs, typically in such a situation?

Worst case; the "magic smoke" comes out of your generator.

does it cause home appliances to "burn"...?

Usually not.

does a generator experience permanent harm from an overload, assume it's not repeated

Yes, it can.
You need to know your load. You already seem to know the relationship between current and power. One way to manage your load is to build a simple adapter so that you can use a cheap "clamp on" AC ammeter to measure current. Another way is to use a manual transfer panel with built- in wattmeters. A common way is to keep track of what you have connected to the generator and estimate your total load using simple addition.
My whole-house generator is only 4 KW. That means that I must shut down my central air, my oven & range (hot water is gas). That done, our typical load is under 2 KW. Why so small? Because we can have weeks-long power failure in our area and even that little generator could burn hundreds of $ worth of fuel in a single week. Imagine what a big one could cost to run?
Vaughn

when generator is overloaded

am attempting to size a generator and have a couple stupid questions. assume a generator wired via manual or automatic transfer switch, nominally providing about 3-5 kilowatts of power, about 22-24 amps apart from an overload shutting down a generator, what else occurs, typically in such a situation? does it cause home appliances to "burn" or do these typically just shut off similar to what would happen when a power utility has what is called a "brown out" or low voltage situation? sometimes our local power utility has multiple back-to-back low voltage events, causing appliances to stop-start-stop how does a "brown out" differ from a generator overload caused low voltage shut down, aside from the fact that the generator of course will turn off and the power outage becomes a "black out". does a generator experience permanent harm from an overload, assume it's not repeated


to add to the good reply from Vaughn .. Prudent load management is the key - if you want to run your home from a 3 - 5 kw generator. I have a Honda 5000 that feeds my home quite nicely .. - except - I shut off everything else - when I need to pump water. No big electric heater elements and no air cond. No "idle down" fuel savings - the phantom loads will easily beat-out the idle-down limit. ( 40-50 watts ) Fuel consumption - I can just barely make it through the night on a tankful .. 7 hours.. at nothing near full load .. 3 - 4 gallons. That said - I have sat through 30 hour southern Canadian February grid power failures while the gas furnace, gas water heater, fridge, freezer, computer, TV, lights, etc are quite happy .. If your needs are more critical - or for long duration - do not rely on a little 3600 rpm consumer generator. They are also quite noisy. I can't say that I've had my generator poop-out or overload under critical load .. I can't say how the loads would react. jt

when generator is overloaded

"Mark L." wrote in message

am attempting to size a generator and have a couple stupid questions.
assume a generator wired via manual or automatic transfer switch, nominally providing about 3-5 kilowatts of power, about 22-24 amps
apart from an overload shutting down a generator, what else occurs, typically in such a situation? does it cause home appliances to "burn" or do these typically just shut off similar to what would happen when a power utility has what is called a "brown out" or low voltage situation? sometimes our local power utility has multiple back-to-back low voltage events, causing appliances to stop-start-stop
how does a "brown out" differ from a generator overload caused low voltage shut down, aside from the fact that the generator of course will turn off and the power outage becomes a "black out".
does a generator experience permanent harm from an overload, assume it's not repeated

Inverter generators will simply shut down the output if overloaded. I doubt they would cause any spikes or low voltage problems.
My personal experience with overloaded generators is that (usually) the circuit breaker trips. Or the coils burn out or melt. None of my non-inverter generators will "shut down" due to an overload. At least not to my knowledge. Some generators will keep struggling along without tripping the breakers but you should be able to hear it struggling and the lights will be dim etc.

when generator is overloaded

"Ulysses" wrote in message

"Mark L." wrote in message am attempting to size a generator and have a couple stupid questions.
assume a generator wired via manual or automatic transfer switch, nominally providing about 3-5 kilowatts of power, about 22-24 amps
apart from an overload shutting down a generator, what else occurs, typically in such a situation? does it cause home appliances to "burn" or do these typically just shut off similar to what would happen when a power utility has what is called a "brown out" or low voltage situation? sometimes our local power utility has multiple back-to-back low voltage events, causing appliances to stop-start-stop
how does a "brown out" differ from a generator overload caused low voltage shut down, aside from the fact that the generator of course will turn off and the power outage becomes a "black out".
does a generator experience permanent harm from an overload, assume it's not repeated
Inverter generators will simply shut down the output if overloaded. I doubt they would cause any spikes or low voltage problems.
My personal experience with overloaded generators is that (usually) the circuit breaker trips. Or the coils burn out or melt. None of my non-inverter generators will "shut down" due to an overload. At least not to my knowledge. Some generators will keep struggling along without tripping the breakers but you should be able to hear it struggling and the lights will be dim etc.


Depending on the design and size of both the motor driving it and the alternator different things can happen

If you overload the alternator to the extent that it exceeds the capability of the motor to supply enough power to drive it and it is a straight forward motor alternator (not an inverter model), the alternator will slow down causing the frequency to drift, any electric motor on the electrical system will also slow down, or could stall. Electric motors prefer a fixed frequency or cycles (Hz) The more you overload it the slower the alternator will turn and the slower the electric motors will run. If the overlaod is severe enough it could cause the motor driving the alternator to stall.

Most alternators are capable of a limited overload for starting purposes of electrical motors, but a sustained overload will cause the breaker to trip or and the burning out of the alternator.

Running an alternator above its rating for any length of time can cause the windings to overheat and be damaged, and although this might not at the time be sufficient to cause the alternator to burn out then, it could cause problems later on in shortening the life of the altermnator.


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