WTD Step down transformer 240V to 100V

[Berni217]

Hello all,

I am looking for one of those for a new Power Amp from Japan.

The transformer will need to handle at least 500VA (W).

Thanks.
B.


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[Barry]

Japan uses two different mains voltages and frequencies: 100V/60Hz and 200V/50Hz. The former is used primarily in the west of the country. the latter in the east. (To be precise the electric frequency is different on either side of the Fujigawa River in Shizuoka Prefecture and Itoigawa City in Niigata Prefecture, with 50Hz in the east and 60Hz in the west.)

Whilst your primary concern is being able to run the power amplifier on our 230V/50Hz mains, power transformers designed fo 60Hz supplies may 'hum' when used on 50Hz aupplies.

[Wakefield Turntables]

Barry, how the hell do you know this stuff??? :scratch:

[Pigmy Pony]

Barry, how the hell do you know this stuff??? :scratch:

He was an extra in Karate Kid Part 2. He was Mr Miyagi's TV repair man :)

[walpurgis]

Barry, how the hell do you know this stuff??? :scratch:

:) Barry's knowledge amazes me too, as did Andre's when he was here.

[Berni217]

Japan uses two different mains voltages and frequencies: 100V/60Hz and 200V/50Hz. The former is used primarily in the west of the country. the latter in the east. (To be precise the electric frequency is different on either side of the Fujigawa River in Shizuoka Prefecture and Itoigawa City in Niigata Prefecture, with 50Hz in the east and 60Hz in the west.)

Whilst your primary concern is being able to run the power amplifier on our 230V/50Hz mains, power transformers designed fo 60Hz supplies may 'hum' when used on 50Hz aupplies.

Hi Barry,

Thanks for the info.

The Amp’s power input is 100v 50/60 Hz, hence should be fine with our UK frequency.

Cheers.


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[Barry]

That's good - the transformer has sufficient margin to run at the lower frequency.

Basically running a transformer designed for 60Hz at 50Hz increases the flux density in the core by 20%, so the core losses will be greater and thus the running temperature will increase. Also with an increased flux density, you run the risk of core saturation if the transformer has been built with a minimum necessary core cross-section (to save cost).

All transformers 'hum' to a certain extent - the hum is due to mechanical vibration caused by magnetostriction in the transformer core, and the effect depends on the magnetisation in the core. So with a potential 20% increase in magnetic flux density, the 'hum' level will increase. Again this can be minimised with good core design.

[Berni217]

Thanks Barry,

The Amp is from Wavac who has a solid reputation in transformer design / or using some of the best in the market.

Cheers.


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[Cotlake]

https://airlinktransformers.com/category/japan-uk-voltage-converters

[Berni217]

https://airlinktransformers.com/category/japan-uk-voltage-converters

Thanks for the url.

I have used Airlink’s transformers before. They are good but have increased their price a lot in past years, hence too expensive.

The displayed prices do not factor for VAT and shipping that need to be added on top.


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[Monty]

I have this variac available if it is of interest?

https://i.postimg.cc/RZdQYcyB/274-D28-B5-2-F07-4689-B489-2-D06763-C7672.jpg (https://postimg.cc/zyLgbRqt)
https://i.postimg.cc/fRDf5HHC/0-AA2-D0-E3-A2-EE-419-D-AE0-C-33799-ADA0-F45.jpg (https://postimg.cc/QHY7dqZK)

[Berni217]

I have this variac available if it is of interest?

https://i.postimg.cc/RZdQYcyB/274-D28-B5-2-F07-4689-B489-2-D06763-C7672.jpg (https://postimg.cc/zyLgbRqt)
https://i.postimg.cc/fRDf5HHC/0-AA2-D0-E3-A2-EE-419-D-AE0-C-33799-ADA0-F45.jpg (https://postimg.cc/QHY7dqZK)

PM sent.


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[Monty]

PM replied to.

[struth]

ive a variac(homemade) that i used to use on a jap amp too. still have both somewhere. a useful thing to have

[Berni217]

I am now sorted thanks all.


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