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120V MOT transformer on 220V for spot welding machine? Answered

Hello i'm making a Spot welding Machine using a microwave transformer i'm removing the secondery coil to replace with 2 rounds of very thick wire for the output .
the only problem is the transformer rated for 120V input
Will it matter if i connect the primary to 220v ? i'm replacing the secondery anyway ?


You'll find it will probably throw the circuit breaker. The core will saturate, and there will be no impedance to the flow of current. Bang.

I tried it for a split second and that's exactly what happened

Thank you for explaining good thing i have a 220v to 110v transformer i guess i'll be using instead of connecting the 120v spot welder transformer directly

you'll move the problem up the chain, unless that transformer is wildly overrated for the 120. Transformer

Here is what i did i connected the step down transformer 220v in and 110v out then connected the microwave transformer on the 110v out from first transformer and it worked perfectly , i also tried welding with the custom MOT secondery i've made and it's working perfectly i'm sure the 10v gonna make a slight performance decrease but that's better than blowing up the fuses

see what your stepdown transformer is rated for. Knew somone who plugged an air compressor into one and it blew the fuse.

hi im dheeraj can i make any modification so that i can give 220v 50hz to 120v rated transformer