Calling on any Electrical Engineers

I know dangerously little about electricity and how power supplies work other than its totally magical to me. I have been in discussion with a supplier in the United States about a power supply for a turntable and there was a question whether it would convert from the 115v to the 230v that comes out of my wall.
He has sent me a picture of the inside of the power supply and said I just have to turn the internal switch to 230.
Now I was looking at the transformer and it says 115V on it.
So the question is, is he right and it will work fine here or is the transformer itself an issue?
Apologies if this is a stupid question…

The indication is that there are two windings for 115 volt - wire them in parallel for 115v, or in series for 230 volt. If there is a suitable switch that switches between 115 and 230, then it would be fine. I assume that the little switch there does the different wirings for you.

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Thanks Beachcomber!
I just found the following in the stats sheet from the manufacturer “For 230 volt operation, connect primaries in series by connecting pins 5 & 4 together and apply 230 volts across pins 6 & 3”
So it is, I assume, as you say that the switch performs that function.
Thanks again!

I Confirm - the little black switch changes the primary winding voltage between 115v & 230v.

Briliant! Thanks a lot.

That’s a centre tapped earth CTE transformer, so 115v 0v 115v for the US and 230v if needed by switching over. Very importantly though the US mains is cycled at 60Hz and in the UK we use 50Hz. This might affect speed control, it certainly would for a directly wired AC motor. I would ask if the outer of the power supply casing stated 50/60Hz or not, if it does then it should be fine on both but we wary if it just says 60Hz.

Is that a Chinese made power supply ?

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Thanks Pipdan I will check. None of these things would have come to my mind without the forum so thanks a bunch!!

I really don’t know where the power supply is manufactured but it’s for a pretty high end turntable that I’m seriously thinking about.
Why do you ask - do you think it has any bearing?

I was just wondering about its origin. The soldering on the output connector doesn’t look the best and the mains wiring could be better. Shorter L&N connections between mains input socket and board for a start and more importantly the earth should really connect to the metal chassis (via a bolt and lug) rather than to the PCB (unless it’s hidden underneath the mains socket).

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Hi James_n - thanks for your comments. I will check with the supplier regarding the earthing. I don’t think there is anything to be done about the rest :thinking:

And yet you made a plea to electrical engineers to advise you on whether to turn a knob!

I don’t think the mains frequency will be an issue since the output of the unit as a whole is DC presumably.

Bear in mind that in order to be safe, there will likely also need to be a fuse change in the PSU as well to whatever rating has been tested and approved safe for that voltage. You should probably speak to the manufacturer for advice here.

Thanks everyone - I have fired off an email with all the questions and concerns raised and lets see what comes back. If I am going to take the plunge on this I really need to be sure on all the details.

Can’t you find a service manual on line for it with a wiring diagram in it plus instructions

So I just mailed the manufacturer and it is in fact an AC motor.
He also says that the 50/60 hz doesn’t matter as the frequency for the motor is generated in the electronics (sorry bad translation from the German) - I don’t really understand this…
Also the earth is connected to the chassis apparently.

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That’s pretty light on details but if they said it is all okay, (I assume you did say what you wanted to do and they gave you the all clear), then you have all the info you need to know.

Is this a replacement power supply / speed control for the Rega mentioned in your system profile or for something else. I’m just wondering what you are trying to do ?

The Rega is no more - sold it at the weekend!
This is the power supply for the Palmer 2.5i that was built by Acoustic Signature in Germany for the American market hence all the back and forth on voltage conversion etc…