Critical feedback request - Consumer unit.

[MrShine94]

Hello, Please can I have some feedback on the quality of a fuse board I installed recently. I am fairly new to consumer unit installs. Newly qualified.

 

[cliffed]

Looks neat,not sure of the actual workings of the system.
Where’s the bottom main switch fed from.

 

[Cid]

Looks very good

 

[Midwest]

Does look good, be prepared to be ripped apart though

Have you used ferrules on your RCBO fly leads?

 

[Spoon]

Have you used ferrules on your RCBO fly leads?

I'm presuming you only need to add ferrules if you shorten the lead, or do you guys add them anyway?

 

[telectrix]

only thing i can fault is the bunch of cables coming in top left.some vertical plastic trunking would look better. otherwise a very neat job.

 

[DT1991]

Looks neat,not sure of the actual workings of the system.
Where’s the bottom main switch fed from.

Looks like the SWA is a 4 or 5 core.

 

[Lucien Nunes]

What is the deal on that big bunch of T+E exiting to the left? Have any applicable grouping factors been applied to the cables or is that not how they will be on the day? In an installation like this it is usually impossible to load them all heavily due to the limited total supply, but if some are run near their limit this can overcook them a little.

You've got nice long service loops on the L & N, not sure whether there is the same on the CPCs. I always like to make sure there are a few inches spare for re-termination by taking them across the board and back or around in a curve.

Can't see the armoured termination which is often a variable in an otherwise good install.

I know few people do this on a domestic install but I always number the cables with the appropriate DB way, to avoid frustration if multiple cables are taken out duing an EICR.

But yes, generally pretty smart.

 

[MrShine94]

Looks like the SWA is a 4 or 5 core.

Yes that is true the bottom main switch is for the off peak supply feeding storage heater and immersion

 

[MrShine94]

Does look good, be prepared to be ripped apart though

Have you used ferrules on your RCBO fly leads?

No none of the boards have ferrules I understand that is a requirement but my foreman will not listen.

 

[MrShine94]

only thing i can fault is the bunch of cables coming in top left.some vertical plastic trunking would look better. otherwise a very neat job.

We are installing 200 of these board in a council estate. The cables on the left are being boarded .

 

[Lucien Nunes]

If the flylead is fine-stranded and has been cut and terminated in a terminal that is not designed for fine-stranded cable, then that is a genuine defect in the work. Bring your own ferrules or leave the full length of the flylead so you can terminate using the original crimped / spotwelded end.

 

[MrShine94]

If the flylead is fine-stranded and has been cut and terminated in a terminal that is not designed for fine-stranded cable, then that is a genuine defect in the work. Bring your own ferrules or leave the full length of the flylead so you can terminate using the original crimped / spotwelded end.

Thanks for your reply I agree with what you are saying. I have previously uploaded a past board from this job and received the same feedback. My foreman is refusing to purchase ferrules does not think they are needed.

 

[telectrix]

show him reg. 526.9. ( from 17th . 18th. may be different number.).

 

[Baddegg]

Don’t fret, neatness comes with experience

 

[Midwest]

I'm presuming you only need to add ferrules if you shorten the lead, or do you guys add them anyway?

They don't look like they have them, so guess they've been shortened.

Edit, op's replies just bee added.

 

[Spoon]

show him reg. 526.9. ( from 17th . 18th. may be different number.).

No, same number in 18th.

 

[Dustydazzler]

Nice job

Why is there a piece of cardboard wedged down the back of the consumer unit ? Packing to get level ?

 

[Martin Kerr]

You need to colour identify you bottom neutral

 

[Charlie_]

Top and bottom on the same phase?
Could do with sleeving the incomers.

 

[Wilko]

Good on you for asking .
Re the bottom row - out of habit I put the isolator on the end. As you've shortened the RCBO N lead, these can't easily be moved now. And yes, if you are going to shorten that N lead it needs to be ferruled. If there's room (seems plenty here) I would use the RCBO as they're supplied.

 

[MrShine94]

Nice job

Why is there a piece of cardboard wedged down the back of the consumer unit ? Packing to get level ?

No that is the tub strap box used for fixing the SWA

 

[MrShine94]

You need to colour identify you bottom neutral

Yes your right thanks for the advice

 

[baldelectrician]

The only thing that looks a bit suspect is the fact that they are Proteus.

 

[dksanders]

Nice looking job, good to see when someone takes pride in the end result. Agree with all the other comments and will add; don't forget to fill those gaping cable entry holes (the top one's going to be a bitch) with intumescent seal or equivalent fire stop especially as the unit is mounted on a wooden backboard.

 

[Midwest]

Can't be arsed with arguing, but where does that ---- come from?

 

[dksanders]

Can't be arsed with arguing, but where does that **** come from?

17th Edition Amendment 3, 421.1.201 (ii)
states that consumer units shall be enclosed ...etc.

You can hardly call the CU enclosed if there's a gapping big hole in the back, especially as it's pointing at an easily combustable material such as wood.

The intent of that reg is to ensure the fire containment of the enclosure is maintained, which it isn't with a big hole in the back facing wood. It would be fine if it was mounted on a non-combustable wall, but it's not.

Think about it, what's the point of having metal enclosures, metal self closing doors over the mcbs, having to fit non combustable blanks, all designed to keep a fire within the CU, then a big hole that a fire can escape out the back of?

A couple of intumescent pillows stuffed in the holes will suffice.

 

[Midwest]

17th Edition Amendment 3, 421.1.201 (ii)
states that consumer units shall be enclosed ...etc.

You can hardly call the CU enclosed if there's a gapping big hole in the back, especially as it's pointing at an easily combustable material such as wood.

The intent of that reg is to ensure the fire containment of the enclosure is maintained, which it isn't with a big hole in the back facing wood. It would be fine if it was mounted on a non-combustable wall, but it's not.

Think about it, what's the point of having metal enclosures, metal self closing doors over the mcbs, having to fit non combustable blanks, all designed to keep a fire within the CU, then a big hole that a fire can escape out the back of?

A couple of intumescent pillows stuffed in the holes will suffice.

I'm freshly back.

Reg 421.1.201, item (ii) refers to using a enclosure made from combustible material to be installed in a cabinet or enclosure made from non combustible material, i.e. comply with (i) or (ii).

MythBreakers videos - https://www.hager.co.uk/news-exhibitions-case-studies/news/amendment-3-to-bs-7671-2008/mythbreakers/56067.htm?mainvideoid=6dnZNI0bzRk

Unless they have changed the reg again in the 18th (I only have the BYB), there is no requirement to use intumescent seals in a CU made from non combustible material, only to maintain the IP ratings as per reg 416.2.1 (BYB). I don't believe the back of a CU requires this rating, although if someone could access the back, it would make common sense to maintain a similar IP rating.

 

[Squid]

Don’t fret, neatness comes with experience

It takes a real expert to do a messy install though ;o)))))

 

[Squid]

Does look good, be prepared to be ripped apart though

The breakers are leaning slightly to the right ;o))))

 

[Baddegg]

The breakers are leaning slightly to the right ;o))))

Oh no! The BBC will be round to sort that......

 

[Squid]

Oh no! The BBC will be round to sort that......

Bites tongue........

 

[DefyG]

Not a great fan of Proteus boards but if that's what you have been given to work with!
What is the max demand as looks like only 10sq supply on my old screen but a lot of final circuits.
Probably is 16sq just looks a bit small but I'm sure you or the designer have done the calcs.
But yes nice neat job.

 

[DefyG]

The breakers are leaning slightly to the right ;o))))

Never ever found any PC ones they all seem to lean one way or the other!

 

[Squid]

;o)))))

 

[dksanders]

I'm freshly back.

Reg 421.1.201, item (ii) refers to using a enclosure made from combustible material to be installed in a cabinet or enclosure made from non combustible material, i.e. comply with (i) or (ii).

MythBreakers videos - https://www.hager.co.uk/news-exhibitions-case-studies/news/amendment-3-to-bs-7671-2008/mythbreakers/56067.htm?mainvideoid=6dnZNI0bzRk

Unless they have changed the reg again in the 18th (I only have the BYB), there is no requirement to use intumescent seals in a CU made from non combustible material, only to maintain the IP ratings as per reg 416.2.1 (BYB). I don't believe the back of a CU requires this rating, although if someone could access the back, it would make common sense to maintain a similar IP rating.

Reg 421 etc actually says it shall "be enclosed in a cabinet or enclosure", I don't view having a large hole at the back as being 'enclosed'.

That video only stats that Hager, have done the tests, it doesn't cover all CU manufacturers, and he actually ends by saying "you may need to use some of these to maintain IP standards" (Intumescent seals etc.)

Normally I would totally agree with you but it's the fact that the material behind the hole is highly combustible i.e. wood and you have to consider External Influences i.e. BE2 - Fire Risks, characteristics required for 'erection' are equipment made of material retarding the spread of flame. Air, comprising that opening doesn't comply with that.

and CB2 - Propagation of Fire; erection characteristics required are Fire barriers, again air and wood aren't a fire barrier.

There's quite a large stand off gap between the CU and the wooden back board; if there was a fire in any of these CU's they're installing, air will get sucked in from around the CU and they'll be a blow torch effect out of the back of this hole, onto the wood, but if you still think that it complies and is no risk because the rest of the case is made of metal, then so be it.

 

[Midwest]

Reg 421 etc actually says it shall "be enclosed in a cabinet or enclosure", I don't view having a large hole at the back as being 'enclosed'.

That video only stats that Hager, have done the tests, it doesn't cover all CU manufacturers, and he actually ends by saying "you may need to use some of these to maintain IP standards" (Intumescent seals etc.)

Normally I would totally agree with you but it's the fact that the material behind the hole is highly combustible i.e. wood and you have to consider External Influences i.e. BE2 - Fire Risks, characteristics required for 'erection' are equipment made of material retarding the spread of flame. Air, comprising that opening doesn't comply with that.

and CB2 - Propagation of Fire; erection characteristics required are Fire barriers, again air and wood aren't a fire barrier.

There's quite a large stand off gap between the CU and the wooden back board; if there was a fire in any of these CU's they're installing, air will get sucked in from around the CU and they'll be a blow torch effect out of the back of this hole, onto the wood, but if you still think that it complies and is no risk because the rest of the case is made of metal, then so be it.

I've read 421.1.201 many times; there's an OR between indent (i) & (ii), which means you can do either. Or do you place all your metal CU's inside a non combustible enclosure? There's no mention of using intumescent seals.
I must be reading your replies incorrectly.

In the Hager vid, Steve York only refers to seals/glands to maintain the IP standard; intumescent seals are not normally used to achieve a particular IP rating.

Electrical Safety First; https://www.electricalsafetyfirst.org.uk/media/1503/consumer-unit-mythbuster.pdf

If you chose to fill holes & entries with intumescent strip, thats up to you, but there is no requirement to do so, at the moment.

Metal CU's of the current design, are not fire proof, and if a fire did start inside one, would not fully contain it

When all these concepts about non combustible enclosures & reg 421.1.201 came into being the, the talk by some was to remove a source of fuel from a fire, not to try & contain it. IET have since changed this philosophy. If the design was to contain a fire in a domestic CU, it would need a complete design change.

I note that Wylex offer some intumescent pads for their CU's. They have produced a vid comparing CU's side by side under fire test. Quite frankly, I can't see an improved performance;
How to improve on Amendment 3 | Voltimum - https://news.voltilink.co.uk/articles/how-improve-amendment-3

 

[Wilko]

Tellingly (if that’s a real word) they’ve had to put 700W of heating inside the CU to get some “action” in this test. And as you say, both CU went ok - neither had flames licking out. But then we weren’t told if they’d left the back cutouts in place or open etc.
Looking at the Wylex site they’ve an intumescent pad they put in the front flap. If that’s what they’ve used in the test I’m not really surprised at the result, as IMHO the metal flap does the necessary.