How fast should a capacitor lose it's charge?

[Edtwozeronine]

I've been testing some capacitors off a treadmills PCB using a 9 volt battery to charge them up, then taking voltage readings with a multimeter and watching as they discharge.

Most seemed to release the 9v very slowly but one 25v 470uF capacitor leaked it away considerably faster than the rest. Is this a sign of a bad capacitor that needs replacing?

Is it worth buying those capacitor testers for £10-12 off eBay for further tests?

 

[Edtwozeronine]

Back to the main issue as it were, I've reinstalled my treadmills circuit board after installing a few new capacitors and it came on but give an error code E02. After a bit of Googling I found 2 answers to fixing this error code, one was to swap the circuit board for a new one, about 125 dollars on alibaba or was it AliExpress? The other, check the lead from the circuit board to the motor, which I did as part of the reinstallation process.

Anyone worked on treadmills or in electrical repair?

 

[Edtwozeronine]

Oh, I also found out what the small black push button on the circuit board does, it seems to test the incline motor, it takes it up 1 level of incline and back down again. All the time I was working on the circuit board I wondered what that was for...

The E02 error comes after the count down to start the treadmill motor by the way.

 

[l4urence]

I used to test using an ohmmeter to charge, the voltage charged the capacitor - so 0 ohms becomes infinity as a short circuit becomes an open circuit - the capacitor is charged. Then discharge using voltmeter, voltage decreases to zero. Very basic but worked in the day (moving coil meters).