Other Amps

maybe a stupid question

1

Hi all, just wondering if this is a supremely stupid question. Does anyone know if its safe to use a US amp with old 2 prong plug into a step down transformer for use in the UK? I gather that the danger with the old 2 prongs is that there is no earth/ground but the step down transformer surely grounds it to a regular 3 prong UK plug. Does that sound right?

2

As I see the step down transformer itself is properly grounded, but if the amp is only connected with 2 prong, then any failure with the amp that causes voltage to be connected the amp metal chassis will still be dangerous as the amp chassis is not grounded.

Cheap safety measure is to use residual current device http://www.olympustoolhire....

3

Jukka is correct. If the amp has only 2-core cable then it will not be earthed, no matter about the earth pin on the step-down. The step-down will be earthed, but the amp will not.

I may be wrong, but I don't think it's that big a deal to convert a 2-pin US amp to 3-pin - I believe you just need to ground the amp chassis to earth by replacing the mains cable and plug with a 3-core one.

NB: DON'T DO THIS UNLESS A REAL AMP GUY HAS SAID IT'S OK.

JBGretschGuy or Billy Zoom will be able to confirm.

4

What Deke said... DON'T DO THIS UNLESS A REAL AMP GUY HAS SAID IT'S OK.

5

Not a stupid question at all. RIP Keith Relf.

6

HMMmmm, I believe the only "stupid" question is the one that is not asked?

7

Thanks very much for the advice. Probably best to get a 3 prong cable put on it to be safe. Cheers

8

Where are you, tabletop? I’m guessing UK. You should be able to find a good amp guy locally to do the mod, but if you’re anywhere near North Kent I can put you in touch with a good one.

9

I'm in London Deke...i know a couple of amp techs I can ask to do it. Many thanks

10

Good idea to change the 3 prong cable. Still will not harm to use the residual current device for additional safety with "suspicious" equipment. It will prevent you getting electrocuted also in other cases that are not covered by the earthing the chassis. Costs only 10£ https://www.amazon.co.uk/Ad...

https://www.electricalsafet...


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