KSC HK33 blowing fuses

wKnight · December 7th, 2007, 18:38

I have a KSC HK33A2 and it is blowing fuses like mad. The odd thing is nothing is broken or damaged in the mechbox. The gears turn freely and the motor still runs fine when pulled out of the gun. Also the gun can still be manually cocked and fired. I am a bit stumped on this one so any suggestions would be appreciated.

DC_ACU · December 7th, 2007, 19:07

bad wiring or bad battery maybe

ThunderCactus · December 7th, 2007, 19:22

This happens in electric grinders, the shaft in your motor could be bent causing direct contact inside, making the fuse blow. Try a different battery first. If you need to get a new motor, a TM EG700 is a good choice.

wKnight · December 7th, 2007, 19:55

tried 2 batteries, same thing. If the shaft in the motor was bent I would think this might make a distinguishable noise when the motor is run externally wouldn't it?

wKnight · December 7th, 2007, 19:59

Quote:

Originally Posted by DC_ACU

bad wiring or bad battery maybe

the motor runs fine externally off of the guns wires so i think the wires are ok.

Tankdude · December 7th, 2007, 20:04

What size fuses are you blowing?

wKnight · December 7th, 2007, 20:12

15A and a 30A fuse

mcguyver · December 7th, 2007, 20:41

Your motor may run perfectly fine when it's not under load. But it may blow fuses as soon as you apply a load, even a small one.

Measure the current the motor draws with a DC-capable clamp meter or with an DMM rated for at least 10 amps DC in series with the motor. No-load readings in excess of 10 amps means your windings have a short from 1 pole to another. This often occurs at the crossover points at the poles ends, as the windings are pressed against their opposite polarity winding.

It requires you to remove the rotor and pull the windings apart just a bit at the pole ends. This is not for everyday Joe to do, and it's easier to buy a new motor.

If you lack the proper diagnostic equipment to perform simple draw tests, just buy a new motor. But it in-fact may not be the motor (less likely), so you will have to take a chance.

It's highly unlikely that the battery is the problem here, and it could easily be eliminated as a potential problem with a DMM.

Other sources could be motor position, motor height, chafed wiring near pinion gear.

wKnight · December 7th, 2007, 20:57

thanks for the explanation. I do not have these diagnostic tools at my disposal but I can get my hands on another motor to test this theory.

The wires look fine all the way around so I dont think its that. Also with the KSC HK33 there is no way the motor can be out of position, its either in or its out. KSC built it so it has only one position it can sit in.

wKnight · December 8th, 2007, 17:01

thanks for the help, it was the motor.

tracerbullet · February 10th, 2008, 19:25

I know this is a pretty old thread, but out of curiosity what motor did you replace it with? Any standard short type will do? Looking to replace mine currently.

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December 7th, 2007, 18:38	#1
wKnight Trader rating Join Date: Apr 2005 Location: Moncton, NB	KSC HK33 blowing fuses I have a KSC HK33A2 and it is blowing fuses like mad. The odd thing is nothing is broken or damaged in the mechbox. The gears turn freely and the motor still runs fine when pulled out of the gun. Also the gun can still be manually cocked and fired. I am a bit stumped on this one so any suggestions would be appreciated.

December 7th, 2007, 19:55	#4
wKnight Trader rating Join Date: Apr 2005 Location: Moncton, NB	tried 2 batteries, same thing. If the shaft in the motor was bent I would think this might make a distinguishable noise when the motor is run externally wouldn't it? Last edited by wKnight; December 7th, 2007 at 19:58..

December 7th, 2007, 20:41	#8
mcguyver Trader rating Join Date: Aug 2005 Location: Northern Alberta	Your motor may run perfectly fine when it's not under load. But it may blow fuses as soon as you apply a load, even a small one. Measure the current the motor draws with a DC-capable clamp meter or with an DMM rated for at least 10 amps DC in series with the motor. No-load readings in excess of 10 amps means your windings have a short from 1 pole to another. This often occurs at the crossover points at the poles ends, as the windings are pressed against their opposite polarity winding. It requires you to remove the rotor and pull the windings apart just a bit at the pole ends. This is not for everyday Joe to do, and it's easier to buy a new motor. If you lack the proper diagnostic equipment to perform simple draw tests, just buy a new motor. But it in-fact may not be the motor (less likely), so you will have to take a chance. It's highly unlikely that the battery is the problem here, and it could easily be eliminated as a potential problem with a DMM. Other sources could be motor position, motor height, chafed wiring near pinion gear. __________________ Age verifier Northern Alberta Democracy is two wolves and a sheep discussing what's for dinner. Freedom is the wolves limping away while the sheep reloads. Never confuse freedom with democracy.

December 7th, 2007, 19:07	#2
DC_ACU Trader rating Join Date: Apr 2007 Location: Toronto ON	bad wiring or bad battery maybe

December 7th, 2007, 19:22	#3
ThunderCactus Not Eye Safe, Pretty Boy Maximus on the field take his picture! Trader rating Join Date: Feb 2007	This happens in electric grinders, the shaft in your motor could be bent causing direct contact inside, making the fuse blow. Try a different battery first. If you need to get a new motor, a TM EG700 is a good choice.

December 7th, 2007, 20:04	#6
Tankdude Trader rating Join Date: Jan 2005 Location: East Coast, New Brunswick	What size fuses are you blowing?

December 7th, 2007, 20:12	#7
wKnight Trader rating Join Date: Apr 2005 Location: Moncton, NB	15A and a 30A fuse

December 7th, 2007, 20:57	#9
wKnight Trader rating Join Date: Apr 2005 Location: Moncton, NB	thanks for the explanation. I do not have these diagnostic tools at my disposal but I can get my hands on another motor to test this theory. The wires look fine all the way around so I dont think its that. Also with the KSC HK33 there is no way the motor can be out of position, its either in or its out. KSC built it so it has only one position it can sit in.

December 8th, 2007, 17:01	#10
wKnight Trader rating Join Date: Apr 2005 Location: Moncton, NB	thanks for the help, it was the motor.

February 10th, 2008, 19:25	#11
tracerbullet Trader rating Join Date: Oct 2006 Location: Ottawa, Ontario	I know this is a pretty old thread, but out of curiosity what motor did you replace it with? Any standard short type will do? Looking to replace mine currently.

KSC HK33 blowing fuses

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