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Old 30th Aug 2007, 11:33
  #12 (permalink)  
Jabawocky
 
Join Date: Jul 2007
Location: in the classroom of life
Age: 55
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Buster...you are one funny bastard!

OK time for a CORRECTION

Circuit breakers are not an indication at all of the current draw. yes it can be said on a big load you will have a bigger breaker however the circuit breaker is NOT there to protect equipment, it is there to protect the wiring. Otherwise the wires become the fuses and we all know where that ends up.

So think about it a bit closer, depending upon the actual load, the cable run, the environment of the cable, there will be a wire/cable size selected, then a CB is selected to protect the cable. There could be 5 x 3 amp devices powred by a cable with say 30amp rating, and a 20amp breaker.

Its a common misconception, so I am glad for once I can contribute something useful on here!

J

PS some strobes and electric DG's T&B etc draw some serious current! So you never know....the instantaneous current could be higher.....but if the motor runs on and on it will burn out possibly, and flatten the battery! So is it instantaneous current you are arguing over???

Go get a DC tong tester and measure it! its not hard is you have the tools! More trivia for you, the heating element demister in the windscreen of my race car draws about 7.1 amps @ 12vdc......that is more than I expected! Must get warm hey!
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