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Portale generator for High Curent test Set

Portale generator for High Curent test Set

Portale generator for High Curent test Set

(OP)
I need to power a circuit breaker high current test set with a portable generator in order to test the main 3000 amp bolted in breaker.  All power will be off the facility.

The test set normally is powered by a 480 VAC 100 amp single phase circuit in the shop.

Would a three phase 480 VAC generator rated at 100 amps be suitable to power the single phase test set for the short time it takes to test the breaker?  

RE: Portale generator for High Curent test Set

Yeah, should be ok. Not great for the generator if its a long term unbalanced load but for a short test it will be fine. Maybe get a genny slightly larger than 100A rating, and see if you can find out which lines the AVR senses: load those two lines given the choice, unless you have a three-phase sense circuit in which case it doesn't matter.

For a breaker test I doubt you'll need the full driving voltage available from the test set so the chances are your load on the primary side will be less than 100A.
  

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If we learn from our mistakes I'm getting a great education!
 

RE: Portale generator for High Curent test Set

(OP)
Thanks ScottyUK

 

RE: Portale generator for High Curent test Set

Oh, forgot to ask: does the set actually require 100A or is that just the size of the outlet you feed it from?
  

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If we learn from our mistakes I'm getting a great education!
 

RE: Portale generator for High Curent test Set

(OP)
The 100 amps is the size of the circuit that feeds the test set.  The test set is rated at 60,000 amps but we will only be drawing 9000 amps for the long time delay test and 12000 amps for the instantaneous test.
 

RE: Portale generator for High Curent test Set

60kA... I see why it needs a big primary supply!
  

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If we learn from our mistakes I'm getting a great education!
 

RE: Portale generator for High Curent test Set

Yeah, but those fault currents don't have much voltage behind them.

RE: Portale generator for High Curent test Set

(OP)
That is correct. Maybe only a few volts on the output of the test set depending on the impedance of the breaker, connection leads, and test set.

RE: Portale generator for High Curent test Set

We have a number of 60KA High Current Test Sets and test 3200A breakers (full function solid state and Series overloads) successfully with 35KVA Generators.

RE: Portale generator for High Curent test Set

Agreed, we have 100kW generators in our mobile breaker shops, they mostly have 65kA test sets and air conditioning loads and a crane, etc....

RE: Portale generator for High Curent test Set

(OP)
Thanks to all.

 

RE: Portale generator for High Curent test Set

Zogzog

That's an impressive set-up.

RE: Portale generator for High Curent test Set

Thanks, we love our new trailers, plants love them for thier outages too, get one of those on site with 2 techs on days and 2 techs on nights and you can get some breaker work done fast.  

RE: Portale generator for High Curent test Set

  
Keep in mind that the breaker-test set will present a very low power-factor load to the portable generator.
  
 

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