In today's post for the DIY community, I assisted in repairing the motor of a semi-professional slicer.
Before I begin a disclaimer:
All the operations you see were effected by experienced personnel who know exactly how to go about these repairs.
If you do not have the necessary knowledge, do not touch anything at all: you can risk electrocution.
As you know this friend of mine really has golden hands, in fact a few months ago, turning on the slicer he heard sinister bangs as soon as it was turned on.
Turning off the slicer and turning it upside down he noticed the problem right away:
The wires going from the inrush capacitor to the winding were completely without sheathing.
The bangs he heard, therefore were due to the fact that the capacitor instead of discharging on the winding (proper operation) was short-circuited.
Little harm he tells me, just disassemble the motor, open it up, and you change the wires....
Ah, if you say it is so simple...
In less than 3 minutes he had already removed the engine from its compartment and was beginning to open it.
I stopped him because I had to take pictures!!!
Here are a couple of details of the problem
As you can see, the wire insulation sheath has completely deteriorated.
My friend explained to me that it was a gift for his mom and dated back to the 1980s, so with outdated regulations; especially regarding, precisely, sheathing.
Current regulations require that all electrical wires, in addition to the IMQ marking, have self-extinguishing conduits. Top-of-the-line wires have silicone insulating sheaths.
(They even gave me a lesson in electrical engineering!)
Proceeding with the repair work, we disassemble the motor to have free access to the wires, fortunately the short-circuits that were there did not completely ruin the wire, so a small stump remained so we could solder new wire attached to it.
So, out comes the soldering iron and we start soldering the 2 wires.
Before soldering, the stumps of old wire were scratched to remove the oxide (copper green is precisely copper oxide) so that the tin could adhere well.
Soldered the wires and reassembled the motor.
The capacitor wires did not have any kind of problem so they were not replaced, made the connections of the two wires with rope ends and everything is fine.
Note: being AC powered, it does not matter how the wires are connected to the capacitor, in fact every second the polarity is reversed 50 times.
This is why electrical appliances are labeled:
220 V - 50 Hz
Having closed the engine and placed it in its compartment, my friend proceeded to adjust the tension of the drive belts to the blade.
Connected the ground wire to the slicer chassis, reconnected the wires to the switch, and attached the capacitor to its bracket, and the job was done.
We turn the slicer back over and do a test run: the drive belts make a very annoying squeaking noise.
How do we do it?
No problem, a dusting of odorless talcum powder and you'll see it go away!
Said and done, we try to turn it on again and ta da the noise is gone!
And this item was fixed too, see you at my friend's next tool breaking down!