Advice needed -Carbatec AW106PT blowing circuit breaker

[twosheds]

Need some good advice before I head off to the electric motor shop and start spending some dollars (I already have that bad feeling).

Started my AW106PT and it ran for a minute or so under no load then it blew the earth leakage switch. Re-set leakage sitch and same result when I started the machine again. Took the side cover off, electrical type burning smell but no visible signs of any problem with wiring. Started machine and blew earth leakage switch again. This time I noticed a small spark I think from the wiring of the large stop button (still had the side cover off). Tried to start machine a few times but continually blew earth leakage switch. Didn't see the spark again.

Motor body felt hot, even though it had only been running for a minute or so. The cutterhead and the thicknesser rollers all turned okay by hand when I took off both the drive belts. Motor turned okay as well.

The last time I used the machine was a week previous when I was thicknessing 250mm wide boards of brushbox and the same thing happened with it blowing the earth leakage switch. The motor was quite hot to touch and it had that same electricl type burning smell. Anyway I let it cool down because I had been running it for about an hour or so and thought it may have overheated. I started it again 3 hours later and it kept on running. I did notice the machine was running much louder but the extra noise didn't seem to be coming from the cutterhead or the thicknesser rollers.

Anybody had a similar problem with this machine and can offer some advice? Or should I just go straight to the electric motor repair shop? (I already have that sinking feeling).

I have searched this forum and found a plethora of problems with the ML392 (which is what the Axminster instruction manual says my machine is) but nothing specifically about a simple cause for my problem.

Thanks
Twosheds

[elkangorito]

If the earth leakage unit is tripping, it means that there is an earth fault somewhere. Since you say "Motor body felt hot, even though it had only been running for a minute or so", I reckon the motor is cooked.

The easiest way to check this is by conducting an insulation resistance test upon the motor. An electrician will know how to do this & will have the appropriate piece of test equipment.
Alternatively, you could remove the motor & take it to a motor repairer, who can conduct this simple test.

Ideally, insulation resistance tests on motors are best carried out when the motor is not cold. Since there is a fault, it is also advised to have the insulation resistance of the AW106PT electrical wiring checked, ideally with the motor disconnected from the electrical circuit.

Could you please provide details of the RCBO that is tripping i.e. current rating, earth leakage trip rating etc.

[twosheds]

Thanks Elkangorito, I have just had a look at the earth leakage switch. It is rated at 20A / 50hz / 240V. It has 30mA written on it which I am assuming is the trip rating?

The motor on the planer/thicknesser is single phase rated at 1100W (according to the manual). I think I will follow your advice and remove the motor from the machine and take it to the electric motor shop for testing unless I can find an electrician over the weekend (unlikely??).

Regards
Twosheds