In summary:

a. is it still sufficient to seal a new, metal consumer unit to meet IP
ratings without using intumescent glands or the like?

b. is it worth adding something on this to the Wiki on €œChanging a
consumer unit€�? Cock-shy:

€œSealing

After you have tested you should check for gaps which would allow wires
or fingers into the consumer unit.

The only formal requirement is to meet the IP codes [[link to
https://en.wikipedia.org/wiki/IP_Code]]: IP4X on the top surface and
IP2X on other surfaces. But it is good practice to seal all gaps using
conduit, foam strip, glands, or sealant.

You do not have to use intumescent or fire resistant sealant etc.€�

Background

1. Reading the revised article on €œChanging a consumer unit€� (as one is
wont to do when in want of means of procrastination) I wondered about
sealing a CU under the currents regs. Specifically, do the cable
entries need to be fire resistant? And if so, what meets the standard?

2. I dont own the 18th edition but AIUI the requirement is still an
€œenclosure manufactured from non-combustible material€�. Nothing there
about grommets, glands etc.

3. But Wiring Matters[1] in 2015 had a piece which included:

"It is important for the installer to seal all openings into the
enclosure or cabinet for cables, conduits, trunking or ducting that
remain after the installation of cables - see Figure 6. The intent of
the sealing is to ensure that, as far as is reasonably practicable, any
fire is contained within the enclosure or cabinet and the escape of
flames to the surroundings of the cabinet or enclosure or into conduits
trunking or ducting is minimised, as intended by Regulation 421.1.201.
Good workmanship and proper materials must be used, and account must be
taken of the manufacturers relevant instructions, if any.€�

4. That was depressing given I'm inclined to channel Jimmy "Yosser"
Hughes. And wasn't brought up €œproper.

5. But I finally came across another piece from the IET in 2015[2] that
has a Q&A:

€œWhen I put cables into a new metal consumer unit, do I have to use
intumescent glands to enforce the fire protection of the consumer unit?

No, the metal consumer unit is designed to encase a fire within it and
restrict the likelihood that a fire may spread. Manufactures have
carried out exhaustive tests on this issue and have found that the cable
entry does not have to continue the fire rating of the consumer unit,
for it to be effective. The only requirement is to keep IPXXD or IP4X on
the horizontal surfaces (Reg 416.2.1) and IPXXB or IP2X on all other
surfaces (Reg 416.2.2). Intumescent glands and sealants may be used to
ensure the IP ratings are maintained, but they are not a requirement and
existing methods of ensuring IP are acceptable.€�

6. But is that current - and likely to pass "good workmanship"?

[1] https://electrical.theiet.org/wiring-matters/issues/55/
[2]
https://electrical.theiet.org/wiring...rief-overview/


--
Robin
reply-to address is (intended to be) valid

On Wednesday, March 27, 2019 at 8:48:41 AM UTC, Robin wrote:
In summary:

a. is it still sufficient to seal a new, metal consumer unit to meet IP
ratings without using intumescent glands or the like?

b. is it worth adding something on this to the Wiki on €œChanging a
consumer unit€�? Cock-shy:

€œSealing

After you have tested you should check for gaps which would allow wires
or fingers into the consumer unit.

The only formal requirement is to meet the IP codes [[link to
https://en.wikipedia.org/wiki/IP_Code]]: IP4X on the top surface and
IP2X on other surfaces. But it is good practice to seal all gaps using
conduit, foam strip, glands, or sealant.

You do not have to use intumescent or fire resistant sealant etc.€�

Background

1. Reading the revised article on €œChanging a consumer unit€� (as one is
wont to do when in want of means of procrastination) I wondered about
sealing a CU under the currents regs. Specifically, do the cable
entries need to be fire resistant? And if so, what meets the standard?

2. I dont own the 18th edition but AIUI the requirement is still an
€œenclosure manufactured from non-combustible material€�. Nothing there
about grommets, glands etc.

3. But Wiring Matters[1] in 2015 had a piece which included:

"It is important for the installer to seal all openings into the
enclosure or cabinet for cables, conduits, trunking or ducting that
remain after the installation of cables - see Figure 6. The intent of
the sealing is to ensure that, as far as is reasonably practicable, any
fire is contained within the enclosure or cabinet and the escape of
flames to the surroundings of the cabinet or enclosure or into conduits
trunking or ducting is minimised, as intended by Regulation 421.1.201.
Good workmanship and proper materials must be used, and account must be
taken of the manufacturers relevant instructions, if any.€�

4. That was depressing given I'm inclined to channel Jimmy "Yosser"
Hughes. And wasn't brought up €œproper.

5. But I finally came across another piece from the IET in 2015[2] that
has a Q&A:

€œWhen I put cables into a new metal consumer unit, do I have to use
intumescent glands to enforce the fire protection of the consumer unit?

No, the metal consumer unit is designed to encase a fire within it and
restrict the likelihood that a fire may spread. Manufactures have
carried out exhaustive tests on this issue and have found that the cable
entry does not have to continue the fire rating of the consumer unit,
for it to be effective. The only requirement is to keep IPXXD or IP4X on
the horizontal surfaces (Reg 416.2.1) and IPXXB or IP2X on all other
surfaces (Reg 416.2.2). Intumescent glands and sealants may be used to
ensure the IP ratings are maintained, but they are not a requirement and
existing methods of ensuring IP are acceptable.€�

6. But is that current - and likely to pass "good workmanship"?

[1] https://electrical.theiet.org/wiring-matters/issues/55/
[2]
https://electrical.theiet.org/wiring...rief-overview/


--
Robin
reply-to address is (intended to be) valid

Sorry I didn't read all that, but I have to seal top cable openings in a plastic CU, installed to the old regs, and this looks useful

https://www.toolstation.com/intumescent-putty/p19613

Simon.

On Wednesday, March 27, 2019 at 1:12:33 PM UTC, sm_jamieson wrote:
On Wednesday, March 27, 2019 at 8:48:41 AM UTC, Robin wrote:
In summary:

a. is it still sufficient to seal a new, metal consumer unit to meet IP
ratings without using intumescent glands or the like?

b. is it worth adding something on this to the Wiki on €œChanging a
consumer unit€�? Cock-shy:

€œSealing

After you have tested you should check for gaps which would allow wires
or fingers into the consumer unit.

The only formal requirement is to meet the IP codes [[link to
https://en.wikipedia.org/wiki/IP_Code]]: IP4X on the top surface and
IP2X on other surfaces. But it is good practice to seal all gaps using
conduit, foam strip, glands, or sealant.

You do not have to use intumescent or fire resistant sealant etc.€�

Background

1. Reading the revised article on €œChanging a consumer unit€� (as one is
wont to do when in want of means of procrastination) I wondered about
sealing a CU under the currents regs. Specifically, do the cable
entries need to be fire resistant? And if so, what meets the standard?

2. I dont own the 18th edition but AIUI the requirement is still an
€œenclosure manufactured from non-combustible material€�. Nothing there
about grommets, glands etc.

3. But Wiring Matters[1] in 2015 had a piece which included:

"It is important for the installer to seal all openings into the
enclosure or cabinet for cables, conduits, trunking or ducting that
remain after the installation of cables - see Figure 6. The intent of
the sealing is to ensure that, as far as is reasonably practicable, any
fire is contained within the enclosure or cabinet and the escape of
flames to the surroundings of the cabinet or enclosure or into conduits
trunking or ducting is minimised, as intended by Regulation 421.1.201.
Good workmanship and proper materials must be used, and account must be
taken of the manufacturers relevant instructions, if any.€�

4. That was depressing given I'm inclined to channel Jimmy "Yosser"
Hughes. And wasn't brought up €œproper.

5. But I finally came across another piece from the IET in 2015[2] that
has a Q&A:

€œWhen I put cables into a new metal consumer unit, do I have to use
intumescent glands to enforce the fire protection of the consumer unit?

No, the metal consumer unit is designed to encase a fire within it and
restrict the likelihood that a fire may spread. Manufactures have
carried out exhaustive tests on this issue and have found that the cable
entry does not have to continue the fire rating of the consumer unit,
for it to be effective. The only requirement is to keep IPXXD or IP4X on
the horizontal surfaces (Reg 416.2.1) and IPXXB or IP2X on all other
surfaces (Reg 416.2.2). Intumescent glands and sealants may be used to
ensure the IP ratings are maintained, but they are not a requirement and
existing methods of ensuring IP are acceptable.€�

6. But is that current - and likely to pass "good workmanship"?

[1] https://electrical.theiet.org/wiring-matters/issues/55/
[2]
https://electrical.theiet.org/wiring...rief-overview/


--
Robin
reply-to address is (intended to be) valid

Sorry I didn't read all that, but I have to seal top cable openings in a plastic CU, installed to the old regs, and this looks useful

https://www.toolstation.com/intumescent-putty/p19613

Simon.

Actually given the cost of that I might use this:
https://www.toolstation.com/fire-mat...t-310ml/p58145

Read Adams reply in the "Running cables into trunking from CU". It's the same issue.

Richard

On 27/03/2019 13:24, Tricky Dicky wrote:
Read Adams reply in the "Running cables into trunking from CU". It's the same issue.

Richard


Bugger, I somehow missed that thread. It suggests I ought at the very
least to have drafted to steer people towards use of intumescent sealant
as "good practice".

--
Robin
reply-to address is (intended to be) valid

On Wednesday, 27 March 2019 13:12:33 UTC, sm_jamieson wrote:

Sorry I didn't read all that, but I have to seal top cable openings in a plastic CU, installed to the old regs, and this looks useful

https://www.toolstation.com/intumescent-putty/p19613

Simon.

I wonder what the purpose is of bringing a noncompliant CU to another noncompliant standard.

On 27/03/2019 14:33, wrote:
On Wednesday, 27 March 2019 13:12:33 UTC, sm_jamieson wrote:

Sorry I didn't read all that, but I have to seal top cable openings in a plastic CU, installed to the old regs, and this looks useful

https://www.toolstation.com/intumescent-putty/p19613

Simon.

I wonder what the purpose is of bringing a noncompliant CU to another noncompliant standard.


If all the CU needs is some sealant in order to comply with the
standards applying when it was installed I cannot see in what way it
would then still be "noncompliant".

--
Robin
reply-to address is (intended to be) valid

On 27/03/2019 14:22, Robin wrote:
On 27/03/2019 13:24, Tricky Dicky wrote:
Read Adams reply in the "Running cables into trunking from CU". It's
the same issue.

Richard


Bugger, I somehow missed that thread.Â* It suggests I ought at the very
least to have drafted to steer people towards use of intumescent sealant
as "good practice".



I am sure the installation instructions on some metal clad CUs state
that the fire rating of the CU must be preserved.

I always used to silicone up the top entry of the plastic CUs I fitted.
Now I use fire mate etc.

--
Adam

On Wednesday, 27 March 2019 14:55:42 UTC, Robin wrote:
On 27/03/2019 14:33, tabbypurr wrote:
On Wednesday, 27 March 2019 13:12:33 UTC, sm_jamieson wrote:

Sorry I didn't read all that, but I have to seal top cable openings in a plastic CU, installed to the old regs, and this looks useful

https://www.toolstation.com/intumescent-putty/p19613

Simon.

I wonder what the purpose is of bringing a noncompliant CU to another noncompliant standard.


If all the CU needs is some sealant in order to comply with the
standards applying when it was installed I cannot see in what way it
would then still be "noncompliant".

It is, even if you don't see it. Plastic CUs are mostly no longer compliant.


NT

On 27/03/2019 16:45, wrote:
On Wednesday, 27 March 2019 14:55:42 UTC, Robin wrote:
On 27/03/2019 14:33, tabbypurr wrote:
On Wednesday, 27 March 2019 13:12:33 UTC, sm_jamieson wrote:

Sorry I didn't read all that, but I have to seal top cable openings in a plastic CU, installed to the old regs, and this looks useful

https://www.toolstation.com/intumescent-putty/p19613

Simon.

I wonder what the purpose is of bringing a noncompliant CU to another noncompliant standard.


If all the CU needs is some sealant in order to comply with the
standards applying when it was installed I cannot see in what way it
would then still be "noncompliant".

It is, even if you don't see it. Plastic CUs are mostly no longer compliant.


You seem to be assuming this is a newly installed CU. I assumed it was
one installed before compliance with Amndt 3 was required. Perhaps the
OP will clarify.


--
Robin
reply-to address is (intended to be) valid

On 27/03/2019 17:13, Robin wrote:
On 27/03/2019 16:45, wrote:
On Wednesday, 27 March 2019 14:55:42 UTC, RobinÂ* wrote:
On 27/03/2019 14:33, tabbypurr wrote:
On Wednesday, 27 March 2019 13:12:33 UTC, sm_jamiesonÂ* wrote:

Sorry I didn't read all that, but I have to seal top cable openings
in a plastic CU, installed to the old regs, and this looks useful

https://www.toolstation.com/intumescent-putty/p19613

Simon.

I wonder what the purpose is of bringing a noncompliant CU to
another noncompliant standard.


If all the CU needs is some sealant in order to comply with the
standards applying when it was installed I cannot see in what way it
would then still be "noncompliant".

It is, even if you don't see it. Plastic CUs are mostly no longer
compliant.


You seem to be assuming this is a newly installed CU.Â* I assumed it was
one installed before compliance with Amndt 3 was required.Â* Perhaps the
OP will clarify.




I have just had a long day at work.

So help me out.

You seem to be the OP of this thread.

Cheers

--
Adam

On 27/03/2019 17:43, ARW wrote:
On 27/03/2019 17:13, Robin wrote:
On 27/03/2019 16:45, wrote:
On Wednesday, 27 March 2019 14:55:42 UTC, RobinÂ* wrote:
On 27/03/2019 14:33, tabbypurr wrote:
On Wednesday, 27 March 2019 13:12:33 UTC, sm_jamiesonÂ* wrote:

Sorry I didn't read all that, but I have to seal top cable
openings in a plastic CU, installed to the old regs, and this
looks useful

https://www.toolstation.com/intumescent-putty/p19613

Simon.

I wonder what the purpose is of bringing a noncompliant CU to
another noncompliant standard.


If all the CU needs is some sealant in order to comply with the
standards applying when it was installed I cannot see in what way it
would then still be "noncompliant".

It is, even if you don't see it. Plastic CUs are mostly no longer
compliant.


You seem to be assuming this is a newly installed CU.Â* I assumed it
was one installed before compliance with Amndt 3 was required.
Perhaps the OP will clarify.




I have just had a long day at work.

So help me out.

You seem to be the OP of this thread.


Ahem, yes, that should indeed have been "Perhaps Simon will clarify".
Sorry.

(It's tempting to pray say that's what you get from too many 14 hour
days in the past but suspect the truth is just my poor choice of genes.)


--
Robin
reply-to address is (intended to be) valid

On 27/03/2019 16:33, ARW wrote:
On 27/03/2019 14:22, Robin wrote:
On 27/03/2019 13:24, Tricky Dicky wrote:
Read Adams reply in the "Running cables into trunking from CU". It's
the same issue.

Richard


Bugger, I somehow missed that thread.Â* It suggests I ought at the very
least to have drafted to steer people towards use of intumescent
sealant as "good practice".



I am sure the installation instructions on some metal clad CUs state
that the fire rating of the CU must be preserved.

I always used to silicone up the top entry of the plastic CUs I fitted.
Now I use fire mate etc.


I did have a quick look for manufacturers' instructions but all I found
was a rather fluffy Wylex/Crabtree note that repeated the IET line and
then went on to (as I read it) "sell" their intumescent add-ons without
actually saying they needed to be used[1]. But I can well believe some
go further now so it all points to pointing people to use
intumescent/fire rated seals. I'll have another go later.

[1]

G from
https://www.electrium.co.uk/media/20...ccessories.pdf

"The cable installation entry method shall, as far as is reasonably
practicable, maintain the fire containment of the enclosure. This can
generally be achieved by the installer ensuring that the cable access
holes they make in the enclosure do not leave gaps greater than:
 1.0mm for the horizontal top surface and
 2.5mm for all other surfaces

The installer could for example, select as they deem appropriate;
trunking, conduit, cable gland or cable entry accessories to minimise
the opening around the cables. For rear cable access, the minimum number
of rear knockout(s) shall be removed to accommodate the cable(s).

However, customer questions remain as to what further steps could be
taken to ensure that the necessary cable entries do not undermine the
intention of this new and important fire safety requirement.

Intumescent material when exposed to heat rapidly
expands and fills the surrounding area effectively
smothering fire and preventing spread by
extinguishing flames.

The Crabtree Solution

Working with a leading UK manufacturer of
intumescents, Crabtree have introduced the CRFS
range of intumescent material strips which fit inside
the consumer unit (self adhesive). If this intumescent
strip is exposed to heat the fire resistant €œchar€� flows
around the cables filling the enclosure smothering the
fire by reducing the oxygen supply further, so
extinguishing the fire at source."

--
Robin
reply-to address is (intended to be) valid

On Wednesday, 27 March 2019 17:13:17 UTC, Robin wrote:
On 27/03/2019 16:45, tabbypurr wrote:
On Wednesday, 27 March 2019 14:55:42 UTC, Robin wrote:
On 27/03/2019 14:33, tabbypurr wrote:
On Wednesday, 27 March 2019 13:12:33 UTC, sm_jamieson wrote:

Sorry I didn't read all that, but I have to seal top cable openings in a plastic CU, installed to the old regs, and this looks useful

https://www.toolstation.com/intumescent-putty/p19613

Simon.

I wonder what the purpose is of bringing a noncompliant CU to another noncompliant standard.


If all the CU needs is some sealant in order to comply with the
standards applying when it was installed I cannot see in what way it
would then still be "noncompliant".

It is, even if you don't see it. Plastic CUs are mostly no longer compliant.


You seem to be assuming this is a newly installed CU. I assumed it was
one installed before compliance with Amndt 3 was required. Perhaps the
OP will clarify.

No I'm not. But I am concluding from your comments that you don't now how it all works


NT