So a while ago i got my hands on a old sewing machine sadly the foot pedal blew up on me and i also noticed that the machine made my fingers tingle (more on that in this old post here: https://sh.itjust.works/post/35395330 ).
After that i didnt touch the thing for a while but now i needed to sew something so i got myself a new motor and pedal for it online.
The motor fits neat to the machine and the pedal works. But after the last time i was a bit afraid to just touch it, decided to better do a voltage check first.
So i grabbed a Multi meter and connected one side to main earth, and the other side to the metal body of the machine.
And apparently there are 30-32V AC on the metal body of the machine :( Then i tested the current and it was 4.1uA.
I did the same thing for the motor spindle an and the results where even worse >.< 173V AC on the spindle and 43uA when i short it to main earth over the multi meter.
Now my question is:
Is this normal?
Is it maybe just some parasitic currents from the Motor windings acting as antenna and inducting voltage into the metal body of the machine?
Will it kill me if i touch it?
Should i ground the machine to earth using a second plug?
Should i isolate the motor from the metal machine body?
Here are some more pictures from my measurements and measurement setup:
No such thing in there, this is a very old machine there is no electronics inside the machine. The only electronics is the motor itself (bolted to the outside), and the foot pedal that controls the motor (wires go from mains to pedal to motor, there are no wires going inside the machine).
Depending on the type of motor, it may still have a motor capacitor to help it get started. Certain types of electric motors need a capacitor in order to start safely from a standstill, no matter how old they are. (And such motor capacitors can often be pretty large and dangerous.) And even if you're not opening the motor housing where such a capacitor would probably be located, that capacitor will still be connected to certain electrical leads inside the machine, and touching those leads could expose you to it.
So still a good idea to check.