I think that, in that instance, the bigger worry is them having increased your disconnection times to 5 seconds for you!
Using none manufactures parts in CU's re (segregation of lighting circuits and rcd protection)
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So lets have a straw poll?
Who is going to carry a shed load of different MCB's (or make a trip to the wholesaler for virtually every job) so you can always fit the right make?
And who's going to just trust their judgement and fit any make as long as it fits CORRECTLY?
I'm biased by the fact I work in a remote sparsely populated area where I can easily be 50 miles or more from a wholesaler. Under those condition's, I'm not going to make a 100 mile round trip to get a particular make of MCB if I have one with me of a different make but it fits perfectly.
Who is going to carry a shed load of different MCB's (or make a trip to the wholesaler for virtually every job) so you can always fit the right make?
And who's going to just trust their judgement and fit any make as long as it fits CORRECTLY?
I'm biased by the fact I work in a remote sparsely populated area where I can easily be 50 miles or more from a wholesaler. Under those condition's, I'm not going to make a 100 mile round trip to get a particular make of MCB if I have one with me of a different make but it fits perfectly.
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The issue here is that due to some changes in the law manufactures have changed their directives given with some new products..
I am reasonably convinced that many older products did not included any specific instructions at all..
Therefore, we as any users installing a product cannot assume guidance that was not there..
e.g.
several months ago I picked up a couple of Volex MCB's 20A & 16A that were in the
Wozz,
I don't have my book here, but, if you are feeding "into" a CU via an outgoing way then I don't see how it can be on the supply side, however, I don't have the diagram you refer to here, my memory is rubbish, and, I don't know your installs!
I don't have my book here, but, if you are feeding "into" a CU via an outgoing way then I don't see how it can be on the supply side, however, I don't have the diagram you refer to here, my memory is rubbish, and, I don't know your installs!
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The danger being discussed, is if you feed into an MCB that's fed from an RCD, then in the event of an earth fault, the RCD will trip, but all the circuits will still be energised from the PV generator, that will continue to push out power for 5 seconds before it realises it's lost it's grid lock and shuts down.
So a PV inverter must feed into a non RCD protected part of the DB, or a separate DB. (you can use an rcbo if you need rcd protection on the PV circuit)
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The diagram in the back of 7671 is flawed mate.
If you`ve gone onto a way which
1) Isn`t covered by the same RCD as anything else; OR
2) Isn`t covered by an RCD at all AND doesn`t have any other circuits common to the supply side which need a <5s disconnection time AND doesn`t require an RCD.
Then you`re fine, as long as you make clear notification that any circuits connected to the common rail of that OCPD will have a <=5s disconnection time.
However:
Surely it is less fuss and hassle to put a standalone board off the main tails, put in 30mA RCD and appropriate MCB, and label that unit as PV supply ONLY. Added advantage that you are not "last man in" to the existing DB, so cannot be liable for any faults or issues within??
Is my take on it, and is how I instruct / expect anyone installing a system for me to connect it!!!
If you`ve gone onto a way which
1) Isn`t covered by the same RCD as anything else; OR
2) Isn`t covered by an RCD at all AND doesn`t have any other circuits common to the supply side which need a <5s disconnection time AND doesn`t require an RCD.
Then you`re fine, as long as you make clear notification that any circuits connected to the common rail of that OCPD will have a <=5s disconnection time.
However:
Surely it is less fuss and hassle to put a standalone board off the main tails, put in 30mA RCD and appropriate MCB, and label that unit as PV supply ONLY. Added advantage that you are not "last man in" to the existing DB, so cannot be liable for any faults or issues within??
Is my take on it, and is how I instruct / expect anyone installing a system for me to connect it!!!
Dave,
I am more than aware of the danger of the 5sec disconnection time on the inverters vs the 0.4 sec disconnection time in the regs.
There are still ways that this can be wired incorrectly by installers, it is not foolproof.
If you have non RCD ways in the CU you can connect into there, thus feeding into the load side of the RCD's and their associated final circuit MCB's.
There is insufficient clarity in the regs, the solar guidance etc. and a distinct lack of understanding with a LOT of Solar Installers of this issue.
This is ONE of the issues I have already highlighted to "higher powers" and been ignored over!
I am also not the only one to have brought this up.
Anyway back to the mixed MCB thing.
Wozz mentioned in post #37 a point which is moving towards the crux of the matter.
The issue is not with 60898, the issue is with 61439.
Machinery control panels will be built to neither, they will be built to 60204.
Also the manufacturer of the panel will be CE marking and certifying their panel in accordance with the statute law requirements.
Thus they will be undertaking the testing, verification, design checks etc. to provide a declaration of conformity or a certificate of incorporation stating compliance with the relevant requirements.
So one needs to look at this from the other angle, it is not 60898 that precludes their use it is 61439.
You are tampering with the design and certification of the assembled board.
As I have stated, I don't like it, I don't agree with it, but, they have a pretty water tight case as the law and standards sit at the moment.
If you put a "non-standard" MCB into a board, you take on the responsibility for the design, and certification of that assembly in compliance with the product standard.
Would you put a Phillips magnetron into a Bosch microwave if they were obviously different and modify the Bosch unit to accept the Phillips magnetron and then provide this modified microwave oven back to the customer as acceptable?
If you are going to undertake design, modification or build of electrical control panels, motor control centres, panel boards and distribution boards, then I bet that your insurer would be interested?
As if you are fitting a non standard MCB, this is effectively the "case" that the board & MCB maker would be putting together on behalf of HSE, you would also find yourself in non compliance with 7671, manufacturers instructions etc.
As I have said several times, I don't like it and I don't agree with it, however, we can't get away from it.
It is also illegal to sell product without the correct instructions etc. being provided, so B&Q are in breach of the law selling those MCB's in Spec's post #43.
It is quite a complex area of law, and it is rarely used, however, if you have been involved in product acceptances and CE marking of products you would understand.
I am more than aware of the danger of the 5sec disconnection time on the inverters vs the 0.4 sec disconnection time in the regs.
There are still ways that this can be wired incorrectly by installers, it is not foolproof.
If you have non RCD ways in the CU you can connect into there, thus feeding into the load side of the RCD's and their associated final circuit MCB's.
There is insufficient clarity in the regs, the solar guidance etc. and a distinct lack of understanding with a LOT of Solar Installers of this issue.
This is ONE of the issues I have already highlighted to "higher powers" and been ignored over!
I am also not the only one to have brought this up.
Anyway back to the mixed MCB thing.
Wozz mentioned in post #37 a point which is moving towards the crux of the matter.
The issue is not with 60898, the issue is with 61439.
Machinery control panels will be built to neither, they will be built to 60204.
Also the manufacturer of the panel will be CE marking and certifying their panel in accordance with the statute law requirements.
Thus they will be undertaking the testing, verification, design checks etc. to provide a declaration of conformity or a certificate of incorporation stating compliance with the relevant requirements.
So one needs to look at this from the other angle, it is not 60898 that precludes their use it is 61439.
You are tampering with the design and certification of the assembled board.
As I have stated, I don't like it, I don't agree with it, but, they have a pretty water tight case as the law and standards sit at the moment.
If you put a "non-standard" MCB into a board, you take on the responsibility for the design, and certification of that assembly in compliance with the product standard.
Would you put a Phillips magnetron into a Bosch microwave if they were obviously different and modify the Bosch unit to accept the Phillips magnetron and then provide this modified microwave oven back to the customer as acceptable?
If you are going to undertake design, modification or build of electrical control panels, motor control centres, panel boards and distribution boards, then I bet that your insurer would be interested?
As if you are fitting a non standard MCB, this is effectively the "case" that the board & MCB maker would be putting together on behalf of HSE, you would also find yourself in non compliance with 7671, manufacturers instructions etc.
As I have said several times, I don't like it and I don't agree with it, however, we can't get away from it.
It is also illegal to sell product without the correct instructions etc. being provided, so B&Q are in breach of the law selling those MCB's in Spec's post #43.
It is quite a complex area of law, and it is rarely used, however, if you have been involved in product acceptances and CE marking of products you would understand.
The diagram isnt brilliant, and neither is the wording. And I dont think training made the area any clearer. In the instance I was describing I left one unprotected way for the PV, no rcd was needed (unless inverter asked for one as cable route was not needing additional protection, but they rammed a proteus RCBO (presumably as they are cheap)into my MK board, stupid really MK rcbos are not expensive and readily available. I think this should have been picked up on the site survey.
So panel manufactures only use MCBs that allow them to be used in any enclosure? I put a supply into a panel the other week that instructions said it contained 4 crabtree mcbs so whos fault is that now? or have crabtree allowed this? or been consulted? or are the panel manuf taking responsibility? If these rules are taken to the word are MCB manuf going to limit their market to just their enclosures and not other panels? (although the market maybe too small to car about)
So panel manufactures only use MCBs that allow them to be used in any enclosure? I put a supply into a panel the other week that instructions said it contained 4 crabtree mcbs so whos fault is that now? or have crabtree allowed this? or been consulted? or are the panel manuf taking responsibility? If these rules are taken to the word are MCB manuf going to limit their market to just their enclosures and not other panels? (although the market maybe too small to car about)
wozz,
I think you have misunderstood me again.
It is NOT the MCB that is at issue, it is the enclosure.
Thus as the panel maker is certifying the enclosure they take on the responsibility for any of the MCB's therein.
They take responsibility for their panel designs & manufacture as I do when I select the equipment to go into my panels, build them, and certify them as compliant with the relevant requirements.
It is not 60898 that is in "debate", it is 61439, which is the CU std.
I think you have misunderstood me again.
It is NOT the MCB that is at issue, it is the enclosure.
Thus as the panel maker is certifying the enclosure they take on the responsibility for any of the MCB's therein.
They take responsibility for their panel designs & manufacture as I do when I select the equipment to go into my panels, build them, and certify them as compliant with the relevant requirements.
It is not 60898 that is in "debate", it is 61439, which is the CU std.
Im still following sides, my point was what specs said the MK sentry instructions stated them to only be used in MK Sentry enclosures, therefor cannot be used in other enclosrues.
As you pointed out this is about what manuf allow inside their enclosures, so what about enclosures like the GEWISS with din rail in? do they allow MCBs in them? As surely they havnt been tested to the standard that is being referred to?
Or am I barking up the wrong tree?
As you pointed out this is about what manuf allow inside their enclosures, so what about enclosures like the GEWISS with din rail in? do they allow MCBs in them? As surely they havnt been tested to the standard that is being referred to?
Or am I barking up the wrong tree?
Couldn't find the link so here is the same scan of the current Wylex instructions
And it looks like i was lying about the torque settings, Its Logic & Hager that does not give any .
And it looks like i was lying about the torque settings, Its Logic & Hager that does not give any .
wozz,
You may have a point wrt the Gewiss enclosures as an enclosure can be used for many things!
The issue really is heat dissipation from loaded breakers and magnetic affects to adjacent devices.
The internal designs of the breakers are not set in stone, so, it could be that an update to 60898 would be better.
I have suggested this and it could be this standard that is deficient, however, as usual we are the bottom of the food chain and the first in line for the firing squad!
You may have a point wrt the Gewiss enclosures as an enclosure can be used for many things!
The issue really is heat dissipation from loaded breakers and magnetic affects to adjacent devices.
The internal designs of the breakers are not set in stone, so, it could be that an update to 60898 would be better.
I have suggested this and it could be this standard that is deficient, however, as usual we are the bottom of the food chain and the first in line for the firing squad!
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You could have ironed it before you scanned it...Couldn't find the link so here is the same scan of the current Wylex instructions
And it looks like i was lying about the torque settings, Its Logic & Hager that does not give any .
those creases give me a headache!!
]
ROTFWL
Your lucky you dont know what i was doing with that earlier then
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---------- Post Auto-Merged at 21:30 ---------- Previous post was made at 21:27 ----------
I phoned the kids the other day to ask if they knew where the thing that irons the clothes was, they replied 'she left you last week'You could have ironed it before you scanned it...those creases give me a headache!!
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So no C or D types in that CU then?
Good point, i never thought about that as its very rare i fit a C in a C/U (and only ever fitted a few D's in commercial)
yes, providing they are RCBO's to 61009
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Am I missing something, but I can't see the bit where it says you must only use Wylex MCB's.Couldn't find the link so here is the same scan of the current Wylex instructions
And it looks like i was lying about the torque settings, Its Logic & Hager that does not give any .
As far as I can see it just gives the BS No's of what you can use?
It happens to mention in passing the temperature ratings of their own MCB's, but at no point does it say they are the only ones you can use.
So this thread is all a red herring, at least as far as Wylex boards are concerned then.
