Converting 110 volts to 220 volts for ac motor

Thread Starter

prodrumernate

Joined Feb 12, 2020
9
I have a few old microwave transformers. Wondering if i could take that and rewind it to make a step up (i know they are step up transformers) from 110 volts to 220 volts.

I want to test a 220v motor i have been given and see if it is any good or just scrap. only outlet in my house that supplies that power is for my dryer but i dont know if i want to just connect wires directly into to test the motor.

Again its just to test the motor that it works at different speeds.i believe it can handle up to 440v (multiple volts). I can take a picture of the data plate and post and or post motor brand and model if needed. I do have other transformers that i can use but they are rated at 110v at 400hz and is s step down to 29v. those transformers are from torn down aircraft.

oh, also i have a treadmill motor i want to turn into a 36x4 inch belt grinder. any direction into make a driver for that and or just using the one that came with it and rewiring only whats needed to drive the motor please let me know.ill also post that separately.

Side Notes: location is in Arizona so i use 110v outlets.took electronics in high school but that was over 15 years ago so i remember some stuff.also running the 110 to 220 step up transformer allows me to run off a power strip as a safety precaution. im wanting to get back into electronics again and luckily some knowledge i have from high school as well as a power tool mechanic at Sears and Homedepot as well as repairing generators etc at home.just not modifying a transformer and such.
 

MaxHeadRoom

Joined Jul 18, 2013
28,619
Why not try it on the dryer outlet? It would only trip the breaker if a fault occurs.
What is the board part No. for the T.M.?
Max.
 

jpanhalt

Joined Jan 18, 2008
11,087
What is the current requirement at 220V? If, for example, it is 10 A, a step-up transformer with 100% efficiency would try to pull 20 amps and more when starting it. Most of your 110V sockets are not fused for 30A.

I second using the dryer or electric range outlet.
 

Thread Starter

prodrumernate

Joined Feb 12, 2020
9
Why not try it on the dryer outlet? It would only trip the breaker if a fault occurs.
What is the board part No. for the T.M.?
Max.
i am thinking that but wanted to also see about making my own to learn more.but may do that anyways depending on what needs to be done.
 

Thread Starter

prodrumernate

Joined Feb 12, 2020
9
What is the current requirement at 220V? If, for example, it is 10 A, a step-up transformer with 100% efficiency would try to pull 20 amps and more when starting it. Most of your 110V sockets are not fused for 30A.

I second using the dryer or electric range outlet.
sorry, i knew i was forgetting to add some details :)
 

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MaxHeadRoom

Joined Jul 18, 2013
28,619
If you want to take advantage of this motor and also use variable speed, you could run it on a 240v 1ph input VFD, the output of which runs a 3ph motor such as you have.
Max.
 

Thread Starter

prodrumernate

Joined Feb 12, 2020
9
If you want to take advantage of this motor and also use variable speed, you could run it on a 240v 1ph input VFD, the output of which runs a 3ph motor such as you have.
Max.
looks like i would need special equipment to run this or to even test it.i need to figure out what equipment it was pulled from and see if they have to controller for it.
 

sheltonfilms

Joined Feb 11, 2020
12
I'm glad someone caught the 3 phase. I picked it up when it was said it could be wired for 440v (never have seen or heard of a single phase 440v motor).

As far as the treadmill, if it has an MC60 controller just use it. Also grab the choke coil and use it as it keeps the RPMs more steady, without it you can have some pulsing of the rpms. To control it, wire a 5k pot to it.

One issue with treadmill controllers is that once it's turned off, they want to see the speed control brought back to 0 before it will output power again. So if you are working on something, turn it off, and then flip the switch back on, it won't do anything until you reset it back to zero and then bring it back to speed.

To bypass this, add another switch to the wiper (center terminal) of the potentiometer wiring. When you flip the switch it tricks the controller that it's going back to "0" and when you flip the switch back it brings the resistance right back to where you had it.

So you have your main switch (system on) and your engagement switch (turn on motor). If you are working on a project that requires multiple on and offs just leave the main on and when you are pausing just flip the pot switch to temporary turn the motor off.
 

MaxHeadRoom

Joined Jul 18, 2013
28,619
As far as the treadmill, if it has an MC60 controller just use it. Also grab the choke coil and use it as it keeps the RPMs more steady, without it you can have some pulsing of the rpms. To control it, wire a 5k pot to it.

One issue with treadmill controllers is that once it's turned off, they want to see the speed control brought back to 0 before it will output power again. So if you are working on something, turn it off, and then flip the switch back on, it won't do anything until you reset it back to zero and then bring it back to speed.
With the MC-60 there is a mod by removing a resistor close to the centre slider terminal for the pot, I don't remember the res No. offhand. but there are previous posts here with it identified.
With the MC2100 PWM controllers you don't see this condition.
PWM gives a much smoother control down to zero RPM.!
Max.
 
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Thread Starter

prodrumernate

Joined Feb 12, 2020
9
what would be best just to do a "quick" functional test to see if it even works?i got this from work and didnt even ask the guys why it was removed from the equipent.

long term use seems that ill need a little more to it but i cant think of any use for variable speed at this time.

the smaller treadmill motor i wanted to turn into a belt sander, so the variable speed on that isnt a big deal..i will check to see what controller it is..this was a night time grab so i cut a few wires to disassemble it and grab the board and motor as well as a smaller motor.i did trace the wires back and saw the motor wires, lead connections and even disconnected the smaller motor..im not sure there is any speed control knob with it.so i may have to get a pot and try that.next time i wont rush in my tear downs.
 

MaxHeadRoom

Joined Jul 18, 2013
28,619
so the variable speed on that isnt a big deal..i will check to see what controller it is..this was a night time grab so i cut a few wires to disassemble it and grab the board and motor as well as a smaller motor.i did trace the wires back and saw the motor wires, lead connections and even disconnected the smaller motor..im not sure there is any speed control knob with it.so i may have to get a pot and try that.next time i wont rush in my tear downs.
Those such as the MC60 use a simple 5k/10k pot added, but the MC2100 requires a 20Hz PWM input to control RPM.
Max,
 
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