German record player plays at wrong speed in Canada

[Bellatangorra]

Hi,

So i bought a record player in Germany (210V 50HZ) and i recently brought it to Canada (120V 60HZ)
It is working but my record player is not playing at the right speed and even though i can adjust the speed it still isnt right. Does this have anything to do with the difference in V and HZ? I asked at an electronics store and they told me to get a "current transformer". Do i need this? And will it make my record player work normally again?

 

[KJ6EAD]

Is it running too fast? If so, it uses a shaded pole motor that depends on the line frequency to set it's speed. A current transformer will not help. A frequency converter would but it's not a cost effective solution.

 

[Bellatangorra]

Yeah :/

 

[KJ6EAD]

It may be possible to replace the motor with one made for the same line of turntables and intended for sale in the 60Hz world but since you've not included any brand or model information, I can't advise.

 

[shrtrnd]

I had the exact same issue when I brought my 50Hz turntable from Japan, back to the U.S.
My turntable had a jumper plug to change from 50Hz to 60Hz, but guys here told me that's rare these days.
Did you try contacting the maufacturer, or one of their reps in Canada? They will probably provide the best solution.

 

[Bellatangorra]

Yes i will try that!

 

[Gryd3]

Is it running too fast? If so, it uses a shaded pole motor that depends on the line frequency to set it's speed. A current transformer will not help. A frequency converter would but it's not a cost effective solution.

Try ignoring the electronics and taking a look if you can swap out a disk or gear if there is no jumper?

 

[Scotophor]

If it's belt drive, a smaller pulley on the motor might work -- 5/6 the diameter of the original.

 

[Calmore]

As others have said, a 50Hz motor will spin faster on a 60Hz supply. There may also be overheating issues.

If you can furnish us with a brand/model number we might be able to find more. Possibly a pulley can be swapped out or a motor changed.

 

[BobK]

I doubt that they would us a different motor for 50/60 Hz, more likely a different pulley.

Bob

 

[Calmore]

I agree, but a chance different motors were fitted in 60Hz countries.

A simple fix might be to wrap tape around a pulley somewhere, to increase its diameter.

 

[Scotophor]

If it's a belt drive or roller drive, you'd have to add enough tape to increase the diameter of the large turntable pulley by 20%, which is usually not mechanically feasible. Even if it is feasible, you'd have to get it perfectly even, or you'll introduce "wow", especially at the start and end of the tape. Best would be to add a single wrap of material exactly the right thickness, and cut it on an acute diagonal to smooth any bump where the ends meet.

Regarding possible overheating, that would only be an issue going the other way. Inductive reactance increases with increasing frequency, so going from 50 Hz land to 60 Hz (at the same voltage) means that less current will flow through the motor, not more.

 

[Calmore]

What you do with the tape is layer it, making sure each layer is butt-jointed. If done properly no more wow than your average worn out rubber wheel. Not ideal but hey, with a bit of patience it might make an otherwise unusable machine useable. If the machine is more than a few years old alternative pulleys may simply be unobtainable.

If the motor runs faster, the effects of loading and eddy currents must also be taken into account too. Try running a loaded shaded pole motor at a higher frequency and you'll find some of the cheaper ones get warmer (Especially the cheapy un-fanned ones)

 

[Gryd3]

I would probably get a local sign, or machine shop to cut a new pulley for you if you can't find a replacement, some scrap plastic or other thick enough material, and a quick circle and the job should be done. Costs should be minimal unless you want them to do a bunch of other machining. (Check your local hackerspace as well... many have laser cutters and cnc milling machines.)

 

[BobK]

Here is a perfect application for 3D-printer!

Bob