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In Manators thread "is it possible to rewire with no RCD's" the topic of interpreting wiring regulations and signing certificates to declare compliance with regs was raised..
But what happens when the regs aren't clear, or are contradictory...
How do we as individuals decide what is appropriate in order to achieve compliance..
Various schools of thought have been mentioned;
e.g. If these points were in a game of Top-Trumps which items "trump" others?
Can common sense "Trump" the exact wording of regs?
Obviously RCD's are one of the big issues that frequently comes up
(questions like I have to fit XYZ do I need to add and RCD or are the 3036's OK without RCD)
There are others;
etc..
So... I would like to develop this thought about what is the overriding element when assessing if compliance is achieved and what takes precedence when conflicts of thought arise..
This is not to be an argument about the "real meaning of a reg" but more to see how and why people interpret and apply things one way or another, sort of to try and see how and why people think the way they do...
I perceive (maybe wrongly), that there are apparent anomalies about how some regs are applied compared to others..
One of the pivotal conversation points in Manators thread was the reg 701.411.3.3, which I would like to come back to later, but can we leave that to one side for the moment and consider another reg in a hypothetical similar scenario...
Consider the regs 522.6.6 & 522.6.7 Page 100 "about cables buried in walls <50mm"
Lets say we have a kitchen with some 12v SELV lights under some open shelves.
Due to the nature of the kitchen there was nowhere to hide the 12v transformers,
so they are concealed in the roof void and 12v SELV cable are run down the kitchen walls buried less than 50mm deep,
All of the 230v supply to the transformers is surface run back to the fuse box.
So as all 230v is surface there is no need to RCD the supply to the primary of the SELV transformers.
BUT heres the question...
Q1/ As the SELV cables are buried in the walls do we have to apply one of the requirements of 522.6.6 and/or 522.6.7
Because 522.6.6 says in black and white "A cable concealed in a wall or partitioin..etc.. etc.." Irrespective of what sort of cable it is..
Q2/ Do we need to note a departure if we don't follow 522.6.6 / 522.6.7?
Gentlemen (and ladies) Discuss?
:Salute
But what happens when the regs aren't clear, or are contradictory...
How do we as individuals decide what is appropriate in order to achieve compliance..
Various schools of thought have been mentioned;
- Apply sound electrical theory and science to ensure the fundamental safety principals are met.
- Apply a reg word-for-word without looking at is context in relation to other regs within a chapter or section.
- Ignore it and just listen to what another electrician has told me.
- Write comments in departures as a get out clause.
- Keep a level head, balance common sense with electrical knowledge and a reasonable interpretation of the intent of the regulation not necessarily the exact content of the wording.
e.g. If these points were in a game of Top-Trumps which items "trump" others?
Can common sense "Trump" the exact wording of regs?
Obviously RCD's are one of the big issues that frequently comes up
(questions like I have to fit XYZ do I need to add and RCD or are the 3036's OK without RCD)
There are others;
- To bond or not to bond.
- Export the earth or TT the outbuilding
- Does my Cooker / integrated appliance / extractor fan need a local isolator
etc..
So... I would like to develop this thought about what is the overriding element when assessing if compliance is achieved and what takes precedence when conflicts of thought arise..
This is not to be an argument about the "real meaning of a reg" but more to see how and why people interpret and apply things one way or another, sort of to try and see how and why people think the way they do...
I perceive (maybe wrongly), that there are apparent anomalies about how some regs are applied compared to others..
One of the pivotal conversation points in Manators thread was the reg 701.411.3.3, which I would like to come back to later, but can we leave that to one side for the moment and consider another reg in a hypothetical similar scenario...
Consider the regs 522.6.6 & 522.6.7 Page 100 "about cables buried in walls <50mm"
Lets say we have a kitchen with some 12v SELV lights under some open shelves.
Due to the nature of the kitchen there was nowhere to hide the 12v transformers,
so they are concealed in the roof void and 12v SELV cable are run down the kitchen walls buried less than 50mm deep,
All of the 230v supply to the transformers is surface run back to the fuse box.
So as all 230v is surface there is no need to RCD the supply to the primary of the SELV transformers.
BUT heres the question...
Q1/ As the SELV cables are buried in the walls do we have to apply one of the requirements of 522.6.6 and/or 522.6.7
Because 522.6.6 says in black and white "A cable concealed in a wall or partitioin..etc.. etc.." Irrespective of what sort of cable it is..
Q2/ Do we need to note a departure if we don't follow 522.6.6 / 522.6.7?
Gentlemen (and ladies) Discuss?
:Salute