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Isolation transformers & RCD devices

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As simple question (hopefully) - would one of these isolation transformers (240V - 240V) still provide protection from electric shock via an RCD device fitted on my electrical switch board?

http://www.radioparts.com.au/product/54153615/iso2000es-240v-2000va-isolation-transformer-mains-electrostatic-screen#.WlnvHa6WaUk

 

There is mention of "All enclosures are earthed on the input side" - does this mean that after the device there is effectively NO earth (on the device side, not the mains side)? If so, could I employ an RCD after the device to ensure safety.

 

Any advice would be appreciated.

Edited by scumbag

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What is called Safety Earth requires the chassis metal be earthed to the IEC earth tag that then connects to your house wiring earth, which should include a copper rod driven into the actual ground.

http://sound.whsites.net/earthing.htm

 

Using isolation transformers does not remove or change the need of safety earthing. 

 

 

 

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2 minutes ago, stereo coffee said:

What is called Safety Earth requires the chassis metal be earthed to the IEC earth tag that then connects to your house wiring earth, which should include a copper rod driven into the actual ground.

http://sound.whsites.net/earthing.htm

 

Using isolation transformers does not remove or change the need of safety earthing. 

 

 

 

OK it is grounded according to the manufacturer's literature. My question is, will it allow an RCD to trip if a device develops a fault?

Edited by scumbag

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But where is the RCD located ? If it is at the isolation transformer output as an additional safety measure, you are likely to get the first RCD behaving strangely.

 

Using one RCD in this case at the isolation transformer output protects when using that appliance, to the degree that an RCD offers protection, noting there are ratings of RCD  https://en.wikipedia.org/wiki/Residual-current_device

 

This sums it up pretty well.  http://sound.whsites.net/articles/iso-xfmr.htm

"Use of an isolation transformer should be limited only to equipment where it's essential. The rest of the time, equipment should always be connected to the mains in the same way as it is when being used normally. "

 

 

 

 

 

 

 

 

 

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9 hours ago, scumbag said:

As simple question (hopefully) - would one of these isolation transformers (240V - 240V) still provide protection from electric shock via an RCD device fitted on my electrical switch board?

http://www.radioparts.com.au/product/54153615/iso2000es-240v-2000va-isolation-transformer-mains-electrostatic-screen#.WlnvHa6WaUk

 

There is mention of "All enclosures are earthed on the input side" - does this mean that after the device there is effectively NO earth (on the device side, not the mains side)? If so, could I employ an RCD after the device to ensure safety.

 

Any advice would be appreciated.

 

You need to ask Tortech.

 

Some mfrs of 'isolating transformers' take the word 'isolating' to mean that earth is also isolated - ie. the input earth does not follow through to the output earth.  AIUI, this means that an RCD will not work.

 

Other mfrs of 'isolating transformers' take the word 'isolating' to mean that only the active & neutral wires are isolated - by means of magnetic coupling - and the earth wire follows through to the output.  The isotran which Siros made for me a couple of decades ago is like this.  So an RCD works as normal.

 

Andy

 

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59 minutes ago, andyr said:

 

You need to ask Tortech.

 

Some mfrs of 'isolating transformers' take the word 'isolating' to mean that earth is also isolated - ie. the input earth does not follow through to the output earth.  AIUI, this means that an RCD will not work.

 

Other mfrs of 'isolating transformers' take the word 'isolating' to mean that only the active & neutral wires are isolated - by means of magnetic coupling - and the earth wire follows through to the output.  The isotran which Siros made for me a couple of decades ago is like this.  So an RCD works as normal.

 

Andy

 

Tortech says this on their website 

"Earthing is NOT carried to Outlet Socket, Hence Isolated and Floating" 

So that looks like a "no" then. Bummer. 

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9 hours ago, scumbag said:

Tortech says this on their website 

"Earthing is NOT carried to Outlet Socket, Hence Isolated and Floating" 

So that looks like a "no" then. Bummer. 

 

Then look for a different mfr of isotrans, scumbag.  :)

 

Siros was taken over by a Brisbane company - you may be able to find out who?

 

Alternatively, I don't use mine any more - so you might like it?  It's a 1KVA tranny - it weighs 16kg but is not very large - so road transport to Brissie shouldn't be that great, I would've thought.  Attached is a pic of its size, relative to a CD case.

 

It has 1x IEC socket for input and 6x output sockets.

 

Andy

 

Siros Isotran.jpg

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25 minutes ago, andyr said:

 

Then look for a different mfr of isotrans, scumbag.  :)

 

Siros was taken over by a Brisbane company - you may be able to find out who?

 

Alternatively, I don't use mine any more - so you might like it?  It's a 1KVA tranny - it weighs 16kg but is not very large - so road transport to Brissie shouldn't be that great, I would've thought.  Attached is a pic of its size, relative to a CD case.

 

It has 1x IEC socket for input and 6x output sockets.

 

Andy

 

Siros Isotran.jpg

Sign me up! EMMACHESIT?

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