Maintaining top entry fire rating/IP rating

[MickSmith5824]

Evening all

Had a job yesterday, which I'm back at next week. Job was to install new dual tarriff CU. As can see from photo earthing was supplied off a clamp from incoming metallic pipe which contained the supply cables. As this old CU is double packed out with a frame it had ample space to house this pipe. Problem being when fitting new CU this isn't case. So after chat with mr NIC man I opted to drop board by 100mm jigsaw out top entry and use 100mm plastic trunking across top to house these cables and pipe. He seemed bit unsure at first as much as me but checked it out and said that as we have maintained IP4x at top all is fine. I questioned about the fire rating and he said that this is fine to. What are people's thoughts? I'm back there next week so maybe can improve but thoughts are even if use loads of glands on top and trunking on top surely these are only so resistant to spread of fire.
Cheers

 

[Dave OCD]

What you're describing as a 'metallic pipe' looks very much like a two core 10mm or 16mm MICC or 'Pyro' supply cable. So using a pipe earth strap is a right bodge. Ideally this needs a proper gland and to achieve this it would need the existing pot removing to fit the correct gland, along with specialist tools.
Is the CU a long way from the meter ?

 

[MickSmith5824]

What you're describing as a 'metallic pipe' looks very much like a two core 10mm or 16mm MICC or 'Pyro' supply cable. So using a pipe earth strap is a right bodge. Ideally this needs a proper gland and to achieve this it would need the existing pot removing to fit the correct gland, along with specialist tools.
Is the CU a long way from the meter ?

The whole complex is done like this Dave there's about 200 properties. I'm not entirely sure what the proper name for it is but if you look at the photo the pipe comes in and has some sort of orange outer sheath then what looks like copper pipe is exposed and earth clamp is clamped to this. The pipe itself has 4 cores in it all black. 2 for neutral 2 for live with a wax substance around them. Yes the meters are located all the way down on the ground floor

 

[Grant1987]

Evening all

Had a job yesterday, which I'm back at next week. Job was to install new dual tarriff CU. As can see from photo earthing was supplied off a clamp from incoming metallic pipe which contained the supply cables. As this old CU is double packed out with a frame it had ample space to house this pipe. Problem being when fitting new CU this isn't case. So after chat with mr NIC man I opted to drop board by 100mm jigsaw out top entry and use 100mm plastic trunking across top to house these cables and pipe. He seemed bit unsure at first as much as me but checked it out and said that as we have maintained IP4x at top all is fine. I questioned about the fire rating and he said that this is fine to. What are people's thoughts? I'm back there next week so maybe can improve but thoughts are even if use loads of glands on top and trunking on top surely these are only so resistant to spread of fire.
Cheers

The copper pipe you mention is in fact an MICC (pyro) it needs to be glanded properly to your metal consumer unit to achieve a suitable earth. I would imagine that the main service head (cut out) is a fair distance away and not local. Are you working in a block of flats or a big communal building built 40,50 years ago where pyro was used frequently.

 

[Grant1987]

The whole complex is done like this Dave there's about 200 properties. I'm not entirely sure what the proper name for it is but if you look at the photo the pipe comes in and has some sort of orange outer sheath then what looks like copper pipe is exposed and earth clamp is clamped to this. The pipe itself has 4 cores in it all black. 2 for neutral 2 for live with a wax substance around them. Yes the meters are located all the way down on the ground floor

Replied same time as me answered my question ?

 

[Dave OCD]

Yes it's the cable I described Mick 2 cores for the 24 hour supply and the other 2 for off peak presumably. If changing the board I can't see any other correct option other than glanding it properly. If you don't have the experience or tools to do this [and not many have these days to be honest], you might need to ask around and find someone to give you a hand with that part of the job.[Assuming you can still source the right gland] Unless anyone else can suggest another compliant way of connecting the copper sheath to a sizeable earth conductor.

 

[Grant1987]

Yes it's the cable I described Mick 2 cores for the 24 hour supply and the other 2 for off peak presumably. If changing the board I can't see any other correct option other than glanding it properly. If you don't have the experience or tools to do this [and not many have these days to be honest], you might need to ask around and find someone to give you a hand with that part of the job. Unless anyone else can suggest another compliant way of connecting the copper sheath to a sizeable earth conductor.

Is a nightmare these supplies as a way of caution ive run a seperate 16mm earth to each flat on my previous jobs and ensured the pyro cable is glanded correctly to achieve suitable earthing. The responses I got a few years ago made me run seperate earth whilst upgrading kitchens and consumer units

 

[MickSmith5824]

Replied same time as me answered my question ?

Yes it's the cable I described Mick 2 cores for the 24 hour supply and the other 2 for off peak presumably. If changing the board I can't see any other correct option other than glanding it properly. If you don't have the experience or tools to do this [and not many have these days to be honest], you might need to ask around and find someone to give you a hand with that part of the job.[Assuming you can still source the right gland] Unless anyone else can suggest another compliant way of connecting the copper sheath to a sizeable earth conductor.

Thanks chaps. The thing is these apartments were built maybe 80's and all the properties I've worked on in there are done the same way and none are glanded correctly. Don't seem like many sparks nowadays can chuck their hand to this (including me) and don't know what chances are of getting the right glands? Loads of these properties are failing EICR's because no RCD's and not much way getting round this without CU change

 

[MickSmith5824]

Got me thinking how likely it might be that they have also converted the neutral to tncs at supply. There wasn't much sign of this supplies went to a ryfield

 

[freddo]

I'm not entirely sure what the proper name for it is but if you look at the photo the pipe comes in and has some sort of orange outer sheath then what looks like copper pipe is exposed and earth clamp is clamped to this. The pipe itself has 4 cores in it all black. 2 for neutral 2 for live with a wax substance around them.

Even if you don't have the tools or skills, surely you can recognise an MICC cable??!!

 

[MickSmith5824]

Even if you don't have the tools or skills, surely you can recognise an MICC cable??!!

Get a life Freddo

 

[Strima]

There’s no requirement for fire ratings seals on the DB. As this is part of a complex the cable route into the fabric of the building may need fire stopping.

 

[MickSmith5824]

There’s no requirement for fire ratings seals on the DB. As this is part of a complex the cable route into the fabric of the building may need fire stopping.

Thanks Strima good to have it confirmed. Pretty much what NIC said

 

[Dustydazzler]

So long as the correct IP rating for the board is maintained I’m not personally over fuses about trying to fire seal every square millimetre

 

[7029 dave]

Even if you don't have the tools or skills, surely you can recognise an MICC cable??!!

Its a crying shame, because this type of cable is near on extinct certainly on the domestic front.

 

[mattg4321]

Reality is that it’s too costly and time consuming to use when price is a concern.

There isn’t really any reason to use it domestically either imo. Some other wiring type will usually be fine.

Is it even part of college training/am2 anymore? It was when I did my am2 back in 06.

 

[Dustydazzler]

Reality is that it’s too costly and time consuming to use when price is a concern.

There isn’t really any reason to use it domestically either imo. Some other wiring type will usually be fine.

Is it even part of college training/am2 anymore? It was when I did my am2 back in 06.

We certainly made off Micc at college when i did part 1 c&g back in the late 90s.
still stumble across it in older houses but increasingly rarely.
my dad still has some of his old pyro tools but I think the last time that I borrowed them was probably 10 years ago

 

[7029 dave]

Reality is that it’s too costly and time consuming to use when price is a concern.

There isn’t really any reason to use it domestically either imo. Some other wiring type will usually be fine.

Is it even part of college training/am2 anymore? It was when I did my am2 back in 06.

I dont think it is, its not surprising that new sparks have never seen such type cable, clearly shown hear by this very thread.

 

[stevethesparks]

MICC was quite common during my apprenticeship years.
One particular job was a famous stationary shop in New Bond Street, opening up the basement to extend the shop. The whole installation was Pyro (as was best known). I quite enjoyed dressing and installing it. Some old Pubs were also a common place for this.

 

[7029 dave]

MICC was quite common during my apprenticeship years.
One particular job was a famous stationary shop in New Bond Street, opening up the basement to extend the shop. The whole installation was Pyro (as was best known). I quite enjoyed dressing and installing it. Some old Pubs were also a common place for this.

Yep done loads on pubs, fire alarms, church's, it was an every day task back then. Not being a big head but if I had £10 for every termination ive done with the stuff it would go into thousands. lol

 

[pc1966]

MICC was common for fire alarms and industrial control gear many years ago. I guess the appearance of FP rated wire and the time/cost of installing pyro means it is fairly specialised use now. Shame, as it is practically immortal and looked fabulous if bare and polished up!

 

[telectrix]

looked fabulous if bare and polished up..

a bit like 'er indoors then? ?

 

[Dustydazzler]

My wife already wears 8 tins of brasso to keep the fake tan shine going through lockdown ...lol

 

[Strima]

Is it even part of college training/am2 anymore? It was when I did my am2 back in 06.

I got off my bum and did my AM2 in 2016 and it wasn't used then. But SY was???

 

[mattg4321]

I got off my bum and did my AM2 in 2016 and it wasn't used then. But SY was???

Can’t see the point of having SY as part of the exam personally.

Be better off with data/Ethernet, heating system controls and trying to chase in a new socket to an old brick wall with lime plaster - no visible damage allowed! (Ok maybe not the last one)

 

[stevethesparks]

MICC was common for fire alarms and industrial control gear many years ago. I guess the appearance of FP rated wire and the time/cost of installing pyro means it is fairly specialised use now. Shame, as it is practically immortal and looked fabulous if bare and polished up!

I would suggest that there appears to be some instances where its being ripped out - possibly unnecessarily, simply because the electrician of the day doesn't know what to do with it.

 

[Dustydazzler]

Can’t see the point of having SY as part of the exam personally.

Be better off with data/Ethernet, heating system controls and trying to chase in a new socket to an old brick wall with lime plaster - no visible damage allowed! (Ok maybe not the last one)

In all seriousness I think heating controls, solar pv and car charging installation would be far more beneficial these days than micc and sy

 

[freddo]

Spoke to one of the apprentices today, apparently he has done MICC as part of a college assessment, but it is no longer part of the AM2. I certainly remember doing it when I did the AM2. At least they have kept in steel conduit...

 

[UNG]

Even if you don't have the tools or skills, surely you can recognise an MICC cable??!!

Maybe not when you are out of your depth

Given the longevity of Pyro and the many different types of installation it has been used in over the years it is a bit daft that it is not even given a mention on courses these days

Given the possible problems of glanding that pyro properly I think I would be replacing that earth clamp with some constant force springs to clamp the cable to the sheath to maintain the earthing

 

[UNG]

I would suggest that there appears to be some instances where its being ripped out - possibly unnecessarily, simply because the electrician of the day doesn't know what to do with it.

Ripped out and replaced by inferior cable types is usually the norm

The number of times I've seen on forums rip it out and replace it with FP, FP is not and will never be a direct replacement for Pyro IMO

 

[7029 dave]

Ripped out and replaced by inferior cable types is usually the norm

The number of times I've seen on forums rip it out and replace it with FP, FP is not and will never be a direct replacement for Pyro IMO

Unfortunately it comes down to lack of skills, time, money.

 

[UNG]

Unfortunately it comes down to lack of skills, time, money.

But recognising different cable types, their uses and how to handle them is surely a very basic skill whatever level you are at as it is not all T&E in the domestic setting as the OP has found out

 

[7029 dave]

But recognising different cable types, their uses and how to handle them is surely a very basic skill whatever level you are at as it is not all T&E in the domestic setting as the OP has found out

Its a shame the way this industry has become, completely scoped and split into sectors, with that it has its consequences.

 

[telectrix]

then again, how many of today's sparks would recognise lead sheathed twin cable.at first glance, it looks just like pvc/pvc t/e.

 

[pc1966]

then again, how many of today's sparks would recognise lead sheathed twin cable.at first glance, it looks just like pvc/pvc t/e.

Until you go to move it!

 

[UNG]

Its a shame the way this industry has become, completely scoped and split into sectors, with that it has its consequences.

It probably takes longer to become a London taxi driver now than it does to get some basic qualifications to masquerade as an electrician

 

[Dave OCD]

then again, how many of today's sparks would recognise lead sheathed twin cable.at first glance, it looks just like pvc/pvc t/e.

I've got a rewire coming up in a month or so with some of that still currently operational ! It's an old 3 storey cottage,open beams on the ground floor and full of furniture. Can't wait.

 

[westward10]

@MickSmith5824 if you have an issue with any posts then report them by hitting the report button as opposed to insulting forum members. This thread has somewhat drifted off topic which is not uncommon on here.