I am a project manager, constructing new waste water treatment works, for a water company. The contractor building the new works has provided a program which has 4 months between part 1 (dead testing) and part 2 (live testing) of the NICIEC certification. In between these dates, the contractor will test and commission of the plant and equipment e.g. pumps, actuated valves, instrumentation, screens etc.
Would it be correct to say, this does not comply with the wiring regulations ?
AJJewsbury:
the contractor must complete all (dead and live) testing before energising anything
Unfortunately that's impossible. The system must be energised before performing the live tests … not just by definition but by practicality - the very nature of live tests (e.g. loop tests or RCD functional tests) requires the supply to be present & connected.
Dead tests alone should be sufficient prove that the system is safe to energise (that's their purpose) - even though the system still might not necessarily be safe to operate under every situation. It's a subtle distinction - for a simple example, if dead tests show OK, it should be safe to connect a socket circuit to the supply - but what you don't know at that stage as you've not been able to test the RCD is that additional protection can be relied upon - so it might not be entirely safe to plug in appliances (certainly not a long extension lead outside to dodgy hedge clippers kind of thing). Once energised the live tests can be performed. It seems to me the big question is still whether “commissioning” is considered as the same sort of thing as live-testing or the same sort of thing as the installation being “in service" - I guess it's somewhere inbetween.
It gets more complicated when bits of the system are outside of BS 7671 scope - or even worse bits that are in scope are fed from bits that are out of scope. Often understanding and inginuity is needed rather that rigid adherence to a paragraph which may or may not be entirely applicable to a situation.
Hopefully what's really intended is testing of a more progressive nature - live testing things as and when it's practical to do so - while keeping an eye on any residual risks and addressing those by other means (e.g. training) - but at the same time realizing that the ‘milestone’ of all-live-tests-completed might not be completely met until quite a late date.
- Andy.
It goes without saying live tests require energy. I was hoping to keep the conversation very specific about my particular installation which is completely new, so there isnt anything in or out of scope.
What the contractor is proposing will lead to unnecessary risk taking and considered by others, more experienced/knowledgeable than me, to be bad practise.
AJJewsbury:
the contractor must complete all (dead and live) testing before energising anything
Unfortunately that's impossible. The system must be energised before performing the live tests … not just by definition but by practicality - the very nature of live tests (e.g. loop tests or RCD functional tests) requires the supply to be present & connected.
Dead tests alone should be sufficient prove that the system is safe to energise (that's their purpose) - even though the system still might not necessarily be safe to operate under every situation. It's a subtle distinction - for a simple example, if dead tests show OK, it should be safe to connect a socket circuit to the supply - but what you don't know at that stage as you've not been able to test the RCD is that additional protection can be relied upon - so it might not be entirely safe to plug in appliances (certainly not a long extension lead outside to dodgy hedge clippers kind of thing). Once energised the live tests can be performed. It seems to me the big question is still whether “commissioning” is considered as the same sort of thing as live-testing or the same sort of thing as the installation being “in service" - I guess it's somewhere inbetween.
It gets more complicated when bits of the system are outside of BS 7671 scope - or even worse bits that are in scope are fed from bits that are out of scope. Often understanding and inginuity is needed rather that rigid adherence to a paragraph which may or may not be entirely applicable to a situation.
Hopefully what's really intended is testing of a more progressive nature - live testing things as and when it's practical to do so - while keeping an eye on any residual risks and addressing those by other means (e.g. training) - but at the same time realizing that the ‘milestone’ of all-live-tests-completed might not be completely met until quite a late date.
- Andy.
It goes without saying live tests require energy. I was hoping to keep the conversation very specific about my particular installation which is completely new, so there isnt anything in or out of scope.
What the contractor is proposing will lead to unnecessary risk taking and considered by others, more experienced/knowledgeable than me, to be bad practise.
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