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        Discussion Why brushes run out in dc 24 Volt permanent magnet blower motor in short time?

#1 mir_as82 Oct 27, 2012 02:42 PM

Why brushes run out in dc 24 Volt permanent magnet blower motor in short time?
 
brushes and commutator dont have any problem. But brushes are runned out in short time in 24V permanent magnet dc motor.

#2 mjsas Oct 27, 2012 10:51 PM

What do you mean by 'short time'.

I found that a standard automotive windshied washer pump will run a long time at 12 volts but at 24 volts the brushes get hot and break apart in a few seconds. At 18 volts they run OK and make a good fuel pump for a small flame thrower.

Otherwise there is no reason brushes cannot last thousands of hours at any voltage.

#3 mir_as82 Oct 28, 2012 02:39 PM

short time means between 2-6 months.

#4 KenSt Oct 29, 2012 10:26 PM

Wrong spring pressure
excessive amps/sq. inch
comm out of round
wrong brush material

PWM controller pulsing at low frequency

#5 romeodz Nov 05, 2012 03:32 PM

Quote:

Originally Posted by mjsas (Post 23118333)
make a good fuel pump for a small flame thrower

Please elaborate:popcorn:


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