Voltage conversion of Accuphase E-5000

in case the existing transformer is used, how should I use a resister connected in series to drop 20V?

You can use a 680Ω 3W resistor to replace fuse F1.

https://www.vishay.com/docs/28729/pr010203.pdf

@foolishman

Although U.S. mains voltage is rated at 120VAC ± 5%, in some cases household outlets may have voltages as low as 104VAC.

My suggestion would be to power the amplifier with a variac set to 104VAC and see what the highest resistance in series is allowed to turn the amplifier on, if 2kΩ works then it's no problem.

@foolishman 

The E-5000 has an auxiliary transformer that needs to be changed to accept 120VAC mains voltage.

Main transformer voltage conversion is similar to the E-650 and E-600, just move the two plugs and sockets to the middle row.

@foolishman 

Sorry, I don't have voltage conversion information for the E-700, I'm guessing it's probably similar to the E-5000. However, if you could post some pictures of the power supply board, maybe we can figure it out.

@foolishman 

Thanks for posting the E-700 pictures.

To convert the main power transformer primary winding voltage from 100VAC to 120VAC, move connector K1 to K2 and K4 to K5.

However, there is an auxiliary transformer in the upper right corner of your third picture, which supplies power to the standby circuit. It needs to be changed to 120VAC, or use a resistor connected in series to drop 20V so that the existing transformer can be used.

I have successfully converted the E-700 from 100v to 120v

Great! You're most welcome, glad I could help.

I turned the amplifier on with nearly 100VAC and confirmed 2kΩ works... Meanwhile, also I have started discussions about voltage conversion of the E-4000 and the DP-450.

You can use the same method to convert the E-4000 and E-5000 from 100V to 120V.

BTW, if you could post some pictures of the DP-450, maybe we could figure out how to do the voltage conversion.

.

@foolishman

Thank you for the photo. I think the voltage conversion can be done in the PCB on the left, can you post an image of the front and back of that PCB?

@foolishman 

Sorry, I have no experience with voltage conversion with the Accuphase C-47 and PS-1250 either.

I'd love to know how to do that though! If you could provide some close-up pictures of both sides of the power supply board in your threads, maybe we can figure it out.

Converting Accuphase amps from 100v to 120v is not straightforward as the above discussion illustrates. You can never be sure that it was done correctly or to Accuphase standards ("you can use a 680Ω 3W resistor to replace fuse F1"). The above discussion does not inspire confidence, and these units could be a fire hazard.

Thanks for pointing it out! I should have been more specific.

You can use a 680Ω 3W resistor to replace fuse F1.

https://www.vishay.com/docs/28729/pr010203.pdf

The vishay resistor that I recommended is a fusible resistor, it will blow out like a fuse in the event of a short circuit, protecting the circuit from damage and fire.

Fusible resistors are used as safety devices to prevent electrical fires and other damage caused by excessive current being applied at once. They can be found in household appliances like washing machines and microwaves, as well as electronic devices like stereos.

A fusible resistor performs dual functions. Once the power supply is exceeded, then it works like a resistor limiting current. Similarly, once the rating of power is exceeded, then it works as a fuse in the circuit to defend different components within the circuit from the surplus current.

Anyway, my intention is just to help those who have an Accuphase with Japan voltage and want to convert it to 120V or 220/240V, I don’t gain any financial interest from anyone.