240v to110v transformer

I would say that he is only talking about 240 to 110 transformers for caravan etc use. In that case I would believe him because the wiring in the van may not comply. Therefore the whole system would be in jeopardy.

Phil

Hi RA

Yes ,

It will come as a surprise to many
I would like to post the actual replies I received but they are copyright protected & I am not allowed to copy{for my eyes only so to speak }.

But I can assure you that it applies to fully [double insulated ]isolated transformers,not just auto transformers

I have been assured that transformers are just not acceptable, verified by members of the Standards committee according to my source

I agree that a suitably installed permanently wired transformer with a FULLY operational RCD would be "expected to be ok."

BUT that still leaves the question of NON COMPLIANT devices /appliances.switches /plugs etc which are additional breechs of the standards & again has been referred to by ESO

It has really "thrown a cat among the pigeons" as they do not seem to have been aware of the situation

They have simply accepted compliance certificates at face value,as being true & correct.

Two more state ESOs have yet to reply .

PS
One clause that may help is Cl 7.4 of AS 3000 regarding isolated supplies

Peter

Hi Phil
Yes This is relevant to
AS /NZS 3001 :2008
Portable structures

Meaning motor homes vans etc

Hi RA
Of course what you say is correct in that situation
All our mains power operates via stepdown transformer
But each has a specific standard covering them & the application

One reason why AS 3000[wiring rules] has a supplementary code AS 3001 covering transportable structures /
ANYONE working van electricals must have one due to its aplication to THAT specific situation

Peter,
now I have read the replies I can see where you are coming from.

If the transformer was install as a permanent fixture including protection on the incoming side and earth protection on the out going side then wired to the van switchboard and distribution circuits and earthing would it then be acceptable.

RA.

Hi RA
One would think so, but NO ,according to the advise I have recieved, the standards simply do not allow such a set up.
But even if it was ok ,it still leaves the question of non approved devices, as i mentioned & was confirmed by a SEO,

Peter

Hi Dion
What is done at work is not relevent

The relevant standard for vans IS AS / NZS 3001
The situations ARE DIFFERENT
Peter

HI Dion
I would hope that only ONE class 1 devise is being used with such a set up[fully isolated transformer]or multiple class 1, IF the transformer has a permanently fitted& wired, fully functional RCD

In the case of a van ,multiple class1 devises could be connected
Peter

and yet funnily enough 110v step dows are deemed fine to power airplanes when on the ground

Hi
Am I missing something
I do not see the connection
Are planes covered by AS/NZS 3000 & AS/NZS3001
No ,they are not!!
I can assure with planes it is not simply a transformer involved!!
There will be very specific requirements.

Peter

Peter,
interesting replies as you don't know where I work or what industry I work in.
(and it aint aviation!)

However our portable transformers step 115VAC up to 240VAC, with a total of four outlets that can be plugged into. Most have two x double outlet GPO's on the one face of the transformer, some have a double outlet GPO on either face of the transformer.

In my workplace, I authorise there use, and will do so forever a day, until there are sufficient 240VAC outlets available.

Cheers,
Dion.

Hi Dion
No, I do not know where you work, perhaps it is where the Aus standards do not apply?
I assume the transformers are approved fully isolated?
If so ,are you aware that such isolation is only true until a line to earth fault deveops ANYWHERE in the systemi?
It is then NO diffirrent to any other earthed neutral system with it's attendent risk for electric shock
What measures have you taken to avoid that possability??
One is to only use class 2 equipment
Another is to ensure that no more thanONE class 1 devise is connected at any time
Accidents have occurred using multiple class1 devises of so called isolated supplies. & will continue to occur unless the above recommendations are followed.
I await your reply with interest

Peter

Peter,
like you, I am bound by secrecy. I've probably given away, way too much already.

Cheers,
Dion.

Ok, we are not permitted to use earthed neutral systems, I'll let that much on.

Hi Dion

I'll play the game
I suspect you are in mining or some other area where an effective ground may be difficult due to terrain
In that circumstance fully isolated supplies are often used
But I believe you would have some form of RVD, To ensure the isolation was maintained.

I certainly doubt that anyone[who understand] would be silly enough to use multiple class1 devises of any isolated source without some means of determining if isolation has been compromised

Peter
Peter

Hi
Perhaps it appears that way to you.

But it standard with many gov dept!!!
I respect that notification,
However if you have some specific question regarding the matter I will attempt to give you the relevant answers


But I am not in the habit of posting rubbish
I have no need to

It is the information given to me after making enquiries due to another thread on THIS forum ,when I sort confirmation of my understanding of the relevant standards

Just search for "usa 240v t0 110v transformer" & see the disbelieving garbage that is posted on that thread by some self proclaimed experts
You can find the same info IF you know how to ask the question of your state ESO.
Perhaps IF you tell me your state I can give you a direct link.
Peter

Hi Upbeat
This is the reason I will not direct copy

Quote"The information in this e-mail may be confidential and/or legally privileged. It is intended solely for the addressee. Access to this email by anyone else is unauthorised. If you are not the addressee please contact the sender immediately. Any disclosure, copying, distribution, or any action taken or omitted to be taken in reliance on this email is prohibited and may be unlawful" end quote]

Peter

The quote is what every email from business has as a default. If it is a safety issues this should override this or at least you can ask if you can publish it in the interests of safety.
You seem to set yourself up as an "expert' on all matters electrical however we don't know any of your details and you rubbish others.

Quote"Upbeat posted:
The quote is what every email from business has as a default. If it is a safety issues this should override this or at least you can ask if you can publish it in the interests of safety.
You seem to set yourself up as an "expert' on all matters electrical however we don't know any of your details and you rubbish others. "

I have given ALL the details I am prepared to @ this point of time

Perhaps I have asked for permission but been asked not to do so @ this point as it is under further discussion AS I HAVE INDICATED

BUT one POINT IS CLEAR
The use of such transformers IS NOT IN ACCORDANCE WITH THE STANDARDS

Yes, I do come down on unqualified "experts "who PERSIST with their ill informed rubbish

I have given a fair bit of detail on this tread & the other thread

"BELIEVE IT OR NOT", that is your decision.

As I said if anyone wants a detailed explanation, ask the specific question I will endevour to reply in simple terms

BUT I WILL NOT BE POSTING A DIRECT COPY OF THE EMAILS INVOLVED

You seem to think I am making it all up ,why would I bother to do that???

Why should I give my details ,when other"experts "have not.

It not my problem if the disbelievers cause a serious accident to themselves or family
They have been warned

THAT IS THE PURPOSE OF MY POST

Peter

HI All

Here is a direct copy of MY original post to the various ESOs

Quote :"Hi
I wish to seek your advise on the use of complying isolated 240vto110v transformers with imported vans /motorhomes
I am aware that the old version of AS/NZS 3001 made specific mention of such
But no mention is made in the 2008 version
I have heard that they are no longer allowed for this application..
I can understand why that may be so, if used as an isolated supply as this use would ,IMHO, break the standard safety recommendation of only having ONE class 1 devise connected @ any time to an isolated source

Multiple class one device would commonly be connected in the van /motor home situation

A line to earth fault anywhere in the van system would create a floating earthed neutral .but the RCD if fitted would be inopereable
Leaving the potential for a 2nd fault to be a person as with ANY earthed neutral system[it does not have to be M.E.N]

Transformers are being promoted for this apllication ,but by simply wiring them to the supply inlet

I believe the only acceptable way would be to permanently wire them in with an effective RCD on the secondary as per the current standards [create an earthed neutral]

PLUS Main switch & RCD /olcb on the primary
Could you please consider the above & advise your opinion

Thanking you
"end quote}


Other EMails followed between us clarifing certain points ,but I will not be posting them@ this stage

I give permission for any who wish to ask the same question to use my initial
enquiry above.
Peter

HI Geoff
As the rules stand@ this point in time that is the situation.
I may be able to give some further info in time depending on development
as a result of points I have raised
But yes, Now would not be exactly a good time as the cat is out of the bag & on the prowl

Peter

Hi
One Aus transformer maker openly advertises a transformer for that purpose & NOW claims a "clause C 6.11" in the standards allows such use
He simply does not ,or wish to, understand what THAT means

Use as he suggests has never been approved by the relevant standards :AS/NZS 3001:2008

The use of this product in this manner is considered dangerous.


Appendix C 6.11 of AS/NZS 3001:2008 is a New Zealand only normative requirement [referred to on the makers site) that refers to isolation transformers being used in lieu of RCDs for personal protection on external socket outlets of caravans that were manufactured after 1 April 1993.

The clause is not recognised in Australia, and more importantly it does not allow for isolation transformers to be used as a step down transformer for supply to the whole caravan in New Zealand or Australia.


Beware if you are importing or purchasing an import from a dealer
Peter