Accuphase E-408 voltage conversion


Hello,

Maybe someone has experience in converting the voltage for the Accuphase E-408 amplifier from 100 volts to 230 volts?  I tried to find this information on the forum, but without success. 

I would be grateful for a photo of the board with the location of the jumpers for 230 volts.  

Sincerely, Victor.

128x128zeptul

I would try reaching out to Accuphase directly.

My preamp and phonostage are fed by a power supply which provides 12V, and the manufacturer sent a jumper from Europe and the instruction sheet for converting it from 110v to 230v.

(Another US manufacturer’s tube amp was wired to 230v from 110v by a local electronic repair place… they pretty much know how to do it if it is a direct transformer tap, and not via a jumper or two… which does the same thing.)

And PrimaLuna sent the instructions for which transformer taps to move the mains for 110v to 230v conversion.

I suspect that Accuphase would do similar, but that is mostly based upon my positive impression of them as a very reputable high end company. I could be wrong, but my impression is that Accuphase and Luxman are sort of high end there.
(Or I would be pretty surprised if they did not help.)

So it seems like it is worth a try to email them.

Best of luck with it. I suspect it is a nice piece of gear.

(Or it truely sucks and I’ll give $19.50 for it. 😗 )

Thank you for your response, unfortunately the manufacturer does not provide such information. I tried to find a service manual, but it is not freely available.

A photo of the inside might help…
Or a local electronics repair place.

They just put on a transformer and measure the wires from the other transformer taps to find the right ones.

On my Audible Illusions line stage, the transformer is either 110v or 230v, so there was no moving to different winding taps, and they wanted $750 to provide the 230v version. And it still sits on a 230v—>110v transformer.

You should be able to pick up a transformer for going from 230v —> 100v

Thanks for the answer, I can not upload a photo, the forum interface is incomprehensible to me. I have an external step-down transformer, but I would like to convert the amplifier to 230 volts. On various forums, users confirm that all Accuphase amplifiers have multi-voltage transformers that can be switched to 100, 120, 220-240 volts.

In ^that case^ then once it is on the transformer, the electronics place (or the tech) probes the remaining taps to see which one has 220/240v.

Then that is hooked up to the mains, and the 100v tap is disconnected.

One unconnected transformer tap line should read 120v and another 230v or you could have separate lines for 220v and 240v, but I think it I would just be a single 230v.
There should be 3 plus another as a common on one side of the transformer..

The other side of the transformer should have either two coming out going to a diode bridge, and maybe a third line as a common tied to the chassis or the ground.
It is possible that they all come out and go in on the same side.

Is there is a transformer part manufacture and part number on it?

Thanks for the help. I probably won't be able to do this work on my own. I don't know any trustworthy specialists in our city. Probably only a photo of the power board with 230 volt jumpers installed or a service manual would be the ideal solution to my problem. Sincerely, Victor.

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@zeptul

If you can post pictures of the power board (front and back) on your System page, I believe we can figure out the jumper setting for 220,240V mains.

This is an example:

https://systems.audiogon.com/systems/10301

 

 

https://forum.audiogon.com/discussions/accuphase-e600-voltage-conversion

 

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@zeptul please counter check if the jumper positions are correct.

 

 

If the jumpers position are correct, the setting should be as below:

100V mains =  J5, J7, J9

120V mains =  J4, J6, J9   

220V mains =  J5, J8

240V mains =  J4, J8

 

Before changing jumpers, measure resistance across C2, after changing jumpers to 220 or 240V setting, the resistance across C2 should be more than 4X higher.

BTW, 220/240V mains also required changing fuse F2 and soft start resistors jumpers setting. Please provide a photo of showing J1, J2 and J3 so we can figure out its setting.

I also strongly recommend connect a Dim Bulb Tester or an 100watt incandescent light bulb in series to power up the amplifier after voltage conversion. If anything goes wrong, the bulb will simply light up instead of dim down to prevent damage of the amplifier.

 

 

@imhififan ​​​​​​

Thanks a lot for your real help!

Later I will disassemble the amplifier and check the position of the jumpers.

P.S. For some unknown reason, links to photos in my previous posts have been removed.

@imhififan 

I checked everything. You absolutely accurately indicated the position of the jumpers!

Before changing jumpers, resistance across C2 is 0,5 Ohm.

After the prayer, I will start voltage conversion :)

As you advised, I will turn it on through the light bulb.

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@zeptul 

For the soft start resistors, J3 provides highest resistance and should be good for 220V/240V mains, therefore no changes required.

 

@imhififan

I did everything according to your instructions. Jumpers J3, J4, J8 installed (240 volts). The rest of the jumpers have been removed. After setting the jumpers to 240 volts, the resistance between the contacts C2 increased from 0.5 to 2.1 Ohms. Connected power through a 100 watt light bulb. At first, the light bulb burns brightly, then gradually the glow decreases. At the same time, the VU meters light up. Didn’t notice a burning smell. I recorded a video, please watch. Is this a normal reaction? Is it possible to turn on the amplifier directly without a light bulb?

 

@zeptul 

Looks perfect!

The bulb lit up in the first second is due to inrush current  as long as it dim down after that. It is perfectly OK! 

Please go ahead plug it in directly to the mains outlet.

@imhififan 

@holmz 

I checked everything, the amplifier works well.

Thanks for your professionalism. You have done me a great service.

Kind regards,

Victor 

imhififan 

@holmz 

I checked everything, the amplifier works well.

Thanks for your professionalism. You have done me a great service.

Kind regards,

Victor

I could call ^that^ a Victor-Y 😀