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Pete999

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As the title suggests you know what it's like when you are bored and start thinking of times past.
A 230 V supply feeding an isolation Transformer 230V /23OV feeding some equipment, on the Secondary side of the TX a DP RCD is fitted, question if the RCD sees a fault on the equipment will it trip on an Earth fault? the Secondary output is center tapped 110V each side of the Earth.
 
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S

Squid

You set me off Pete, Gwen the 5' 11" half Canadian half Japanese exotic dancer that I had a "dalliance" with 25 years ago........
 

Pete999

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You set me off Pete, Gwen the 5' 11" half Canadian half Japanese exotic dancer that I had a "dalliance" with 25 years ago........
And? more please
 
S

Silly Sausage

You set me off Pete, Gwen the 5' 11" half Canadian half Japanese exotic dancer that I had a "dalliance" with 25 years ago........
I've got say, when thinking of times past, centre tapped transformers aren't really the first things that springs to mind :confused:
 

Pete999

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I've got say, when thinking of times past, centre tapped transformers aren't really the first things that springs to mind :confused:
Yeah well when your memory aint working that well, go with what comes to mind first before you forget it.
 

ipf

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Yeah well when your memory aint working that well, go with what comes to mind first before you forget it.
I'll go with that...…. then again, I can probably remember stand out times 4 decades ago better than 4 months back.......but 4 seconds???? Sounds like it's when you nip out to the wholesalers, arrive and then can't remember what you've come for:rolleyes:
 

Pete999

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Yes because the centre tap is connected to earth so the output is not isolated from earth.
What about if the output volts was 110V Center tapped 55 V each side of earth?
 

davesparks

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What about if the output volts was 110V Center tapped 55 V each side of earth?
It will trip because the output is still referenced to earth, assuming its a regular rcd which will operate at any voltage up to its rated maximum.
 

Lucien Nunes

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An RCD will work downstream of a transformer provided one point on the secondary is earth-referenced (and connected to the load CPC if present.) If that point is also used as a neutral, then the N-E link must be between the transformer and the RCD. E.g. on a 230V TN system, the earth-referenced point is also the neutral; the N goes through the RCD but the CPC does not. On a 55-0-55 site supply, the centre-tap is not used as a neutral but it is still earth-referenced so the RCD will react to a fault on either line.

On non-standard voltages between the outers, the RCD test button may not behave correctly as it will pass the wrong test current.
 
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