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AC motor speed controller for stereo turntable Answered

Hello Brainiacs, I am wondering about salvaging a electric fan speed controller for my Vintage (1980's) Stereo turntable. I purchased a table from Europe and it ran on 50Hz 240v. But once I rewired the unit for 110v 60Hz it still ran too fast. It is a synchronous 24 pole motor driving a small pulley and belt system. I was told a speed controller would fix the issue by varying the voltage. True? Or if someone could come up with a schematic! ??? Any suggestions? 



5 years ago

Just change the pulley sizes by a few percent.

Josehf Murchison

5 years ago

I worked in a shop that rebuilt AC motors from European standard to North American standard.

It is the frequency AC motors speed is regulated by Hz and windings when you go from 50 Hz to 60 Hz the higher frequency makes the motor spin faster.

Changing the voltage to the motor will only reduce your power and slow down the motor by overloading and drive the current up until the motor burns out.

You can rebuild the motor for 60 Hz.

You can change the gearing (a smaller pulley wheel).

Or you can change the 60 Hz to 50 Hz you do this by converting your AC to DC and powering a pure sine wave 50 Hz power inverter chances are you will need to make your own.