8000 watt Portable generator 30 amp

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K8MHZ said:
What has this got to do with this thread?

I asked for an explanation when I said "I'm listening". If it's beneath you to provide one to me, so be it. But at least be forthcoming about it.
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You will know the answer if you follow the line of thought , even if it gets side
tracked by what you label "apples and oranges". All discussions get off track and it's up to the debaters to steer it back in line. Instead you accuse me of saying "nothing to do with the thread".

When you run out of logical response you start fishing for "red herring".
Where did you learn syllogism?
 
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Besoeker said:
What don't have is the kVA rating of the generator. Without that, you can't calculate rated current.
I picture of the nameplate would be helpful.
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I would think that good design practice would dictate that the OCPD, and consequently the configuration of the 240 volt receptacle, would be less than the rating of the generator, lest said generator be put into overload.

Hence, it makes sense to me that a 30 A receptacle (and OCPD) would be used on an 8000 watt (33 and a third A) generator.

The cable connecting the genny to the house could be sized for the above also, and that would make sense to me as well.

In real life, would the kVa of an 8000 watt genny be less than 7200, or 30 amps x 240, making the OCPD too high at 30 amps?
 
K8MHZ said:
So using 8000 watts as the input would be more conservative than the kVa, keeping the OCPD low enough to protect the generator?
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Remember that the continuous load rating of a generator is also limited by the prime mover power.
And since a typical OCPD will hold 135% almost indefinitely the breaker
1. is not going to protect against small overloads, and
2. if too oversized might not even protect against shorts or ground faults because of the output current limit of the generator.
 
K8MHZ said:
So using 8000 watts as the input would be more conservative than the kVa, keeping the OCPD low enough to protect the generator?
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Using the product you posted, the Generac GP8000E, the running output is 8,000 watts, the motor starting output is 10,000 watts. I would assume that if you sent the unit into overload territory it would quickly shut down, depending on its surge capacity.
 
Besoeker said:
What don't have is the kVA rating of the generator. Without that, you can't calculate rated current.
I picture of the nameplate would be helpful.
Click to expand...
The unit has a 30 amp receptacle protected by a 30 amp breaker - 7200 watts is what one should expect to be the maximum available on a fairly continuous basis, any more is going to trip the breaker.
ptonsparky said:
These small generators seem to have big numbers for the peak load or starting capacity, 8000 Watts, then somewhere in the fine print somewhat lower for continuous operation. Or words to that affect.
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I have a 8000 watt unit that also says 13,000 surge (or something very similar to that).

I can tell you the breaker on mine doesn't hold for too long if current gets into the surge rating. Used it many times for running a welder - can't run too hot of weld or for very much duty cycle without tripping the breaker.
 
kwired said:
The unit has a 30 amp receptacle protected by a 30 amp breaker - 7200 watts is what one should expect to be the maximum available on a fairly continuous basis, any more is going to trip the breaker.
I have a 8000 watt unit that also says 13,000 surge (or something very similar to that).

I can tell you the breaker on mine doesn't hold for too long if current gets into the surge rating. Used it many times for running a welder - can't run too hot of weld or for very much duty cycle without tripping the breaker.
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Don't confuse kW and kVA. Except at unity power factor, the kVA will be a higher number than the kW.
The power of the prime mover is likely to rated in kW or HP. That rating will fix (less losses) will fix the power you can get from the generator. Not kVA or Amps.
 
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If you look at the product specs of that generator that was shown in one of the posts the "total rating" is 8000 watts. That's the total wattage the unit will provide. So, you can hook up the 30A - 240V outlet to the house utilizing the interlock kit and still use the two 120V GFCI receptacles to supply some power to your neighbors via extension cords (if you're so inclined). Make sure the unit your customer buys doesn't have GFI protection at the 30A receptacle. If it does, as soon as you plug it into the house side the breaker will trip.

Product Specs
Voltage - 120/240 Single-Phase
Frequency - 60 Hertz
Alternator - Brush
Auto Voltage Regulation - Yes
Surge Watts - 10000 Watts
Rated Watts - 8000 Watts
Fuel Type - Gasoline
Rated Amps 33 Amps
Portability Kit- Never Flat Wheels
Tank Size - 7.5 Gallons
Run Time @ 50% Load - 9.5 Hours
Fuel Tank Material - Metal
Fuel Gauge - Yes
Decibel Rating @ 7m - Not Measured by Manufacturer
Idle Control - No
Hour Meter - Yes
Voltage Meter - No
Lifting Eye - No
Battery - Included
Grade Type - Emergency
 
Besoeker said:
Don't confuse kW and kVA. Except at unity power factor, the kVA will be a higher number than the kW.
The power of the prime mover is likely to rated in kW or HP. That rating will fix (less losses) will fix the power you can get from the generator. Not kVA or Amps.
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I was aware.

Circuit breaker is going to respond to amps. Generator and prime mover can handle nearly twice rating in the unit I mentioned, otherwise it would stall the prime mover.

Once saw the result of a tractor PTO driven generator connected to a tractor with much more output power then the generator rating, that had a line to line fault occur in the connected wiring. My understanding the tractor hardly even grunted, PTO shaft broke a universal joint though.
 
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