Author Topic: Burning electrical smell (Read 4310 times)

TheDonk · « **on:** December 06, 2019, 02:56:48 pm »

Hi,

I have used my SEBO X4 for a number of years and the motor recently appeared to burn out without warning.

I have replaced it with a new one from you. This rotates freely and works but there is a problem. As soon as even a small load is put on it, such as when on a hard floor, there is a strong electrical smell indicative of the brushes arcing badly. On a carpet it is even worse and smells so bad we dare not use it.

I am confident there are no mechanical problems as this new motor turns freely.

Was replacing the motor fixing the symptom and not solving the problem, which still exists.

I have no idea what could be the root cause that replacing the motor hasn't solved and would appreciate any advice or suggestions diagnosing this fault.

MVacs · « **Reply #1 on:** December 07, 2019, 01:33:09 pm »

Was the old motor burned out or did you replace it speculatively?

TheDonk · « **Reply #2 on:** December 08, 2019, 08:31:24 am »

Guess it was replaced speculatively.

It made such an alarming electrical smell we immediately stopped using it, before it seized, melted or caught fire as it seemed to be threatening to do!

On investigating the problem, when it was briefly switched on, the motor would still work but arced alarmingly. I decided to replace the motor as everything seemed to be in perfect working order.

The new motor displays the same problem. Its a puzzle that has got me baffled!

MVacs · « **Reply #3 on:** December 08, 2019, 04:42:20 pm »

The new motor is visibly arcing? You've ran it with the cover off?

Could it be the last one burned out and the residual smell is coming out when the new motor is run?

It seems unlikely a new motor is faulty. How does it sound?

TheDonk · « **Reply #4 on:** December 09, 2019, 11:04:34 am »

Hi,

I have now ran them both with the cover off, the old one arcs really badly and doesn't run properly. In comparison, the new one is now only arcing slightly but runs smoothly - and seems to be getting better with use.

I am now thinking that the new motor's brushes hadn't been bedded in and this caused the arcing and smell when it was initially installed. I was concerned I still had the problem and it could only be caused by a fault in the electronics controlling the motor, which I was clueless about!

On further investigation, I don't believe the motor has any electronics controlling it to go wrong. I have therefore tried running it for longer periods to see if it gets better with use.