Voltage selection in UK

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Guitarman18
Posts: 454
Joined: Tue Sep 04, 2007 9:32 pm
Location: UK

Voltage selection in UK

Post by Guitarman18 »

I'm about to order a set of trannies for my D'clone build and have a question that has been bugging me for a while. My voltage supply here in the UK can vary (from my experience) from 230v to 245v. In order to compensate for this do any of you get your PT's wound with taps that could be used to compensate for these discrepancies (in my case 230, 240 and 250v selectable) or am I being overly concerned about this? It just seems that we spend a lot of time trying to get the internal voltages correct on our builds which can be futile if the mains coming in is so variable.

If anyone has any thoughts or experience with this issue I would really like to know.

Cheers, Paul.
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jelle
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Joined: Sat Feb 04, 2006 7:55 pm
Location: New Jersey

Re: Voltage selection in UK

Post by jelle »

Use a voltage regulator to get the correct voltage for your amp. That's how the pro's do it.

jelle
declan
Posts: 69
Joined: Tue Mar 25, 2008 12:21 am

Re: Voltage selection in UK

Post by declan »

Most European power companies have agreed to a standard which allows 230v +/- 10%, (some claim to provide better than 10% variance).

However your line voltage will also vary depending on the time of day so extra taps would be pointless. If you want to be precise a voltage regulator/line conditioner is the only way.

google them and you will find plenty of options
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Phil_S
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Location: Baltimore, MD

Re: Voltage selection in UK

Post by Phil_S »

Voltage in my house (USA) varies from about 119 to 124. I've seen it at 126 on occasion. The point is, you are not alone.

You should be fine with either a 230V or 240V primary. If you plug a 230V rated into 240V everything will run ~5% hotter. Likewise if you plug a 240V rated into a 230V supply, it will run ~5% colder. Either way, I don't imagine it will be problematic for most amps. A variance of +/-10% inside the amp is generally considered to be on-spec.

The only thing I might look out for is filament voltage not being outside the +/-10% range.
Guitarman18
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Joined: Tue Sep 04, 2007 9:32 pm
Location: UK

Re: Voltage selection in UK

Post by Guitarman18 »

Thanks everyone for the responses. It's nice to know I'm not alone and I will certainly check out a voltage regulator.
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Phil_S
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Re: Voltage selection in UK

Post by Phil_S »

Unless you are subject to frequent extremes that you think affect your tone, I don't think you need a voltage regulator. If you are designing and testing circuits and really do need a constant voltage, then maybe a regulator is worth getting. Even then, only the very costly ones do a good job of delivering a constant voltage. Not worth the expense in my estimation. Just my 2 cents (or 2 pence).
declan
Posts: 69
Joined: Tue Mar 25, 2008 12:21 am

Re: Voltage selection in UK

Post by declan »

After doing sa little research on this myself i agree with Phil. Most specs on the cheap regulators suggest a 20% input tolerance and a 10% output tolerance which will only correct voltage fluctuations by 50%. Not bad but certiantly not providing a rock steady voltage
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