Is this legal?

[Skindy]

Please find enclosed description on how to change over the current unit from Three phase to single phase*1 – The overdoor heater at the moment is running on fan only.2 – Isolate the power supply3 – The current heater elements are wired in three phase format each phase will have a resistance between the phases and no Neutral will be involved. You need to disconnect two of the phases and then make a resistance circuit from the remaining phase to Nuetral !!!!!!!!! Now if there is to much load the single phase power supply will overload so you cannot connect all of the heater battery. You may need some 2.5 cable to hook things up.*1 – Check the fuse and or circuit breaker duty2 – When re starting the overdoor heater make sure there are no smoke detectors close at hand as the elements will smell when first started3 – Make sure you have a clamp meter on the single phase power wire to make sure enough of the existing three phase element has been disconnected to match the single phase power supply available*CheersJohnThis is what my boss wants me to do. This cant be legal.

 

[ian.settle1]

You need to split your question up as I got half way through it and got lost.


And what do you mean legal?

 

[Skindy]

Thats the full email he sent me. Are these instructions legal? Do they comply with IEE 17th edition wiring regulations?

 

[Skindy]

Where did you get up too?

 

[IQ Electrical]

It actually makes sense electrically but in plain English, a large heating load designed to be spread over 3 phases is now on 1 phase only so the design has changed radically and you need to select the supply cable size accordingly.The warranty on the heater will almost certainly be voided, even if the manufacturer has composed the above modification instructions.

 

[Skindy]

Thanks for the advice. Very much appreciated

 

[Adam W]

Is the fan currently being powered by 3 phase, and how would it be powered if this modification were made?
Presumably the fan needs to be running when the heater elements are on.

 

[Electro-tech]

Is this heater refit for a client?? Who ever designs the circuit IMO is legally responsible and should have Public Indemnity Insurance , BS 7671 Regs applied obviously but not a statutory document. Also who ever has it fitted in the event of a fire their Fire policy could be void. I think your Boss is irresponsible to even think about it and involve you aswell.!!

 

[Sparky Ninja]

Thats the full email he sent me. Are these instructions legal? Do they comply with IEE 17th edition wiring regulations?

Two separate questions there.
Are these instructions legal = You would need to refer to some statutory documents.
Do they comply with BS7671 = I would suspect the regs will hide behind the popular 'must be installed to manufacturers instructions' on this one. So in theory, if the manufacturers say it cant be done this way then BS7671 will deem it to be non compliance.