MK Sentry CU
 

On Sat, 30 Oct 2004 08:59:47 +0100, Peter Ramm
wrote:

I have bought MK Sentry Consumer Unit.
I notice that the markings on the plastic for the cable entry cutouts
are all rectangular.
Having made cut-outs is it usual to use any sort of grommet or is it
sufficient to smooth the cut edges of the unit.

(There will also be "gaps" adjacent to cable at entry point - ie
unlike cable in a closed/blind grommet - where it would be possible -
if unlikely - to "poke" in to the unit)

It depends which one you bought. Some of them have hole knockouts
for 20, 25 and 32mm grommets.

For the one that you have, there should be some strips of nylon with
castellations with it which you cut and place around the cut out
section. You should use them and not allow the cables to come into
direct contact with the cutouts.




..andy

To email, substitute .nospam with .gl

Andy Hall wrote:


For the one that you have, there should be some strips of nylon with
castellations with it which you cut and place around the cut out
section. You should use them and not allow the cables to come into
direct contact with the cutouts.

If the grommet strip is missing, you can buy lengths at any electrical
trade counter, and at the bigger sheds (e.g. been-n-queued whorehouse).
It's called grommet strip ;-)

HTH - Stefek

In article ,
Stefek Zaba writes:
Andy Hall wrote:

For the one that you have, there should be some strips of nylon with
castellations with it which you cut and place around the cut out
section. You should use them and not allow the cables to come into
direct contact with the cutouts.

If the grommet strip is missing, you can buy lengths at any electrical
trade counter, and at the bigger sheds (e.g. been-n-queued whorehouse).
It's called grommet strip ;-)

....and if you're really stuck, T&E sheath stripped by running a
knife down the edge of the earth looks remarkably like grommet
strip and is guaranteed not to have a nasty reaction with the
T&E sheath of the cables, but would need glueing in place (as
indeed should grommet strip be).

--
Andrew Gabriel

In article ,
Andy Hall wrote:
For the one that you have, there should be some strips of nylon with
castellations with it which you cut and place around the cut out
section. You should use them and not allow the cables to come into
direct contact with the cutouts.

My recently installed Crabtree Starbreaker didn't have any grommet strip.

I removed all the 'square' knockouts on the back I'd need, and carefully
cut a slightly undersized rectangle in the mounting board. I'd say this is
thick enough not to possibly damage the sheaths.

--
*There's no place like www.home.com *

Dave Plowman London SW
To e-mail, change noise into sound.

"Peter Ramm" wrote in message
...

I have bought MK Sentry Consumer Unit.

Thanks for responses.
Interesting, the first CU I bought from Screwfix had to go back as the
main power switch was cracked. Neither it nor the replacement had any
of the strips provided. I'll get some bought and fitted.
--
Pete Ramm

I've bought a few from there - all have been fine (apart from when they were
out of stock for ages), but as you found - none had the grommet strips
included.

Alex

In message , Peter Ramm
writes
On Sat, 30 Oct 2004 08:59:47 +0100, Peter Ramm
wrote:

I have bought MK Sentry Consumer Unit.

Thanks for responses.
Interesting, the first CU I bought from Screwfix had to go back as the
main power switch was cracked. Neither it nor the replacement had any
of the strips provided. I'll get some bought and fitted.

I fitted a GE cU, it had know either for the square cutouts.

TBH, I'm not sure I see the likelihood of the cable being damaged on the
plastic edge here as any greater than on a junction box, or plastic
mounting box where.

I did think about getting some grommet strip, but I wanted to egt the
box fitted, so it'll ahve to be retro-fitted.
--
Chris French, Leeds

In article ,
chris French wrote:
TBH, I'm not sure I see the likelihood of the cable being damaged on the
plastic edge here as any greater than on a junction box, or plastic
mounting box where.

I'd tend to agree. Grommets for metal boxes are perhaps a different
matter, given the boxes are earthed, and cables might be squeezed into
them. This shouldn't happen with a CU.

--
*If you think nobody cares about you, try missing a couple of payments *

Dave Plowman London SW
To e-mail, change noise into sound.

chris French wrote:
TBH, I'm not sure I see the likelihood of the cable being damaged on the
plastic edge here as any greater than on a junction box, or plastic
mounting box where.

I'd tend to agree. Grommets for metal boxes are perhaps a different
matter, given the boxes are earthed, and cables might be squeezed into
them. This shouldn't happen with a CU.


I was a bit wary when I fitted an mk cu with no grommets - but I did all the
cutouts before mounting it on the wall and used a small file to
cleanup/smooth all the edges. The cables arent very tight fitting and arent
going to move so they should be alright?

Peter Ramm wrote:

(There will also be "gaps" adjacent to cable at entry point - ie
unlike cable in a closed/blind grommet - where it would be possible -
if unlikely - to "poke" in to the unit)

To satisfy the requirements for protection against direct contact, any
enclosure containing live parts - which obviously includes a CU - must
meet IP2x. This means that you must leave no openings through which a
12.5 mm dia. sphere could pass. [Reg. 412-03-01]

In addition any opening in the top surface of an enclosure, if readily
accessible, should meet IP4x. This means having no openings which could
pass a 1 mm dia. sphere and effectively forbids taking open T&E cables
in through grommets in the top of the unit, if the top is readily
accessible. [412-03-02]

--
Andy

Peter Ramm wrote:

[IP4x]
Do you really mean 1mm?

Yes - see http://www.hannainst.com/products/prodline/protect.htm
(amongst many others).

--
Andy