Sealing mains boards

[ChrisElectrical88]

Evening all. I have been carrying out quite a number of EICRs recently as well as Remedials in some pubs and shops. Nearly every mains board I have come across the installer has completely ignored the regulations on IP ratings of the boards. 20mm holes all over the places for 2x1mm cables or 1x2.5mm or 32mm holes for the tails obviously leaving more than the 1mm allowed in the top.

What is the best method to seal these, Silicone seems to be the most practiced method at the company, which whilst is done very neatly still isn't 100% right for fire resistance (I have used 300 degree silicone instead of the normal stuff)

Surely these must be a better way though, how do you do it? Any ideas would be fantastic.

Edit: I know compression glands would be a great solution but they are not always practicable.

 

[Pete999]

Evening all. I have been carrying out quite a number of EICRs recently as well as Remedials in some pubs and shops. Nearly every mains board I have come across the installer has completely ignored the regulations on IP ratings of the boards. 20mm holes all over the places for 2x1mm cables or 1x2.5mm or 32mm holes for the tails obviously leaving more than the 1mm allowed in the top.

What is the best method to seal these, Silicone seems to be the most practiced method at the company, which whilst is done very neatly still isn't 100% right for fire resistance (I have used 300 degree silicone instead of the normal stuff)

Surely these must be a better way though, how do you do it? Any ideas would be fantastic.

Edit: I know compression glands would be a great solution but they are not always practicable.

Blind Grommets, propriety cable entry glands

 

[polo1]

Trunking?

 

[ChrisElectrical88]

Thanks for your answer, I have also used blind grommets where possible, can't however find out if they are fire resistant?

Just looking for a simple solution for such a simple deviation is hard haha.

 

[ChrisElectrical88]

Trunking?

A posibility, however this would effectively mean disconnecting the full mains board in some cases, which would then need to be upgraded to metal in some scenarios to comply. Also above the mains board most of the time is only a inch or so of space, trunking and paxalin would be my choice of weapon if I was installing most of these in the first place.

 

[mattg4321]

They don't really need to be fire resistant/non combustible imo. You can still use nylon glands after A3

 

[Pete999]

Thanks for your answer, I have also used blind grommets where possible, can't however find out if they are fire resistant?

Just looking for a simple solution for such a simple deviation is hard haha.

Is the board plastic or metal?

 

[ChrisElectrical88]

Both. The majority are metal.

 

[saspm]

I have used these on a number of occasions.

British General Fire-Retardant Semi-Blind Grommets 13 Piece Set - http://www.NoLinkingToThis/p/british-general-fire-retardant-semi-blind-grommets-13-piece-set/9638P?kpid=9638P&cm_mmc=Google-_-Product%2520Listing%2520Ads-_-Sales%2520Tracking-_-sales%2520tracking%2520url&gclid=CMiuj_W-_NICFUafGwodthUDdg&gclsrc=aw.ds&dclid=CLawm_W-_NICFRci0wodfYgPPA

 

[Tim Brennan]

I used these recently when I changed my consumer unit.

Wylex Membrane Cable Entry Kit 10 Pcs - http://www.NoLinkingToThis/p/wylex-membrane-cable-entry-kit-10-pcs/4019p

 

[davesparks]

Thanks for your answer, I have also used blind grommets where possible, can't however find out if they are fire resistant?

Just looking for a simple solution for such a simple deviation is hard haha.

Why Dom you want them to be fire resistant? Only the CU needs to be manufactured from a non combustible material, there's no mention of fire resistance

 

[sparkdog]

Wilts sell fire cement sealer I think its called. I use it a lot for gaps and holes around consumer units. It sets nice and solid and is intumesent if that's the right word.

 

[PEG]

Any sealant used,would have to be compatible with the cable sheaths,some cable manufacturers have this information available,as do water and gas pipe makers.

Tapered lead-in open grommets,can make a good job of a retro-fit,on round cables,with a cut to fit.

There is no substitute for doing it correctly,in the first place.

 

[Andy78]

Metal bungs and locknuts is my usual choice to fill 20-32mm holes in boards.

 

[Dave OCD]

So how about when you manage to bring most of the cables in through one of the large rear knockouts, this has to be the easiest way if you have enough length on the cables and can space the board off a little. I'll obviously fit grommet strip but don't attempt any sealing.

 

[freddo]

There seems to be no mention about sealing the back of the boards, just the top surface. I always aim to get all the cables in the back for that reason. I have a hydraulic sheet metal punch set and a load of matching grommets. I just select the size that is just big enough to get all the cables in comfortably, allowing a little space to add future circuits. If there is a big hole in the wall where the cables come through, I do make an effort to seal that before fitting the new board.