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Strange problem with power loss

Strange problem with power loss

Strange problem with power loss

(OP)
Hello,

I have a strange problem I am facing right now and maybe someone here can shed some light on it for me. I designed a rotating clock display that spins about 2000 RPM's and has LED's on it that turn on and off at a high rate of speed to give the illusion of digits in the air. The problem is with the power supply. Since the circuit is attached to a DC motor and spinning so fast there is no way to get power to it via wires for obvious reasons. A battery will not work due to 4 AA cells running out of juice in 3 days. So I came up with a way using magnets (rare earth type) and coils. The magnets are permantily affixed to the base where the motor is attached and arranged in a circular pattern with alternating poles facing upwards. The coils (6) are 26 guage 200 turns each that are spaced equally around the circuit board and about 1/8" spave between them and the magnets. As the motor spins its generating power like an alternator. I then rectify this and put it through a 100uf 25v eletrolyte cap and then 6v regualtor. When I first built it I tested the voltage without load and it was 12v AC and 500+ ma. This is plenty for what I need.

Anyway, the problem is after running for about 5 mintutes the power slowly goes away and the ciruit dies. There is also an odd smell but nothing is getting hot. I know this is a longshot but wondering if anyone here can shed some light on my problem? Could the cap be shorting out on the inside and giving off the smell?

Thanks for any info you can give!

RE: Strange problem with power loss

Having an electrolytic capacitor sitting inside what would effectively be a centrifuge could maybe short it out as the gel migrates under the centripetal force. Maybe a different type of cap or coil/fly back diode.

RE: Strange problem with power loss

(OP)
Thanks for the info!! I wasn't sure about the cap myself but what you said makes alot of sense. I will swap it out and try that. Many Thanks!

RE: Strange problem with power loss

Another thought is that the regulator is actually getting hot internally and going into thermal shutdown even though the outside of the case is cool because the airflow is high.

Let us know what you find.

DspDad

RE: Strange problem with power loss

(OP)
Well I took it apart and I smelled the electrolyte up close and that is the source of the odor. I am going to replace it with a different type and try again...I will get back to you. Thanks!

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