240V AC & red alarm cable run together

[Telecoms_man]

Hi Guys,

Wonder if I may ask a question?

Is it permissible to run the red fire alarm cable with the mains T&E cable, though holes and in the same trunking?

I thought alarms were 24V and that ELV, data, telephone etc & LV should be kept separate?

Maybe there is an exemption for fire alarm wiring as it is screened and fire retardant? If so, I can't find the specific reg.

TIA,
N.

 

[Eire79]

I'm in Ireland , but rules state that cables installed together must be insulated for the highest voltage present and if I'm correct isn't firetuf cable rated for mains 230 v

 

[Phil L]

You can run the mains cable to the fire alarm in line with other mains rated cables, but the fire alarm circuits ( Loop, Zones, Sounders) need to be separated from mains cables under BS5839 to reduce interference

 

[Risteard]

It's not just the LV and ELV issue. As a safety service fire alarm needs to be segregated from other services. Both BS 5839-1 and I.S. 3218 in the case of the poster from Ireland require this.

It sounds like you're referring to FP200 cable, so I'm presuming that this is a commercial or industrial installation (in spite of the reference to T&E being used). You are correct that they are generally 24V.

 

[Telecoms_man]

Hi,

Thank you for your replies so far.

Yes it is a commercial installation. A refurbishment and building extension. Refurbished parts are being re-wired and a new fire alarm being installed. It is FP200 cable, checked today.

First picture shows new cables (grey) coming through a bulkhead wall between two loft areas. Hole could have been drilled at floor level. No attempt seems to have been taken to run the cables neatly or avoid other services. Their own 240V and 24V fire alarm cables run together. White cables clipped to floor are existing intruder alarm cables.

The cables are just run as quickly and as easily as possible in the loft area, over existing walkboards, rather than under, causing both trip hazard and potential damage to the cables when they get walked on or loft gets filled with junk. Many are run diagonally around the loft. No sign of a single cable clip anywhere on the T&E. Has made my work so much harder, trying to find ways to route my cables to avoid the mains stuff. A little more care by them would have made their job look so much neater.

Second photo shows the new fire panel. FP200 cable is crossing the T&E, running in the same trunking.

Picture 3 shows an earth bar in the trunking. At least it has one screw in it. Don't know where the end of the cable goes, I'm guessing water or gas. both are easily accessible, so whilst this would not break any regs, it would be neater to renew the full length.

Picture 4 is a joint in the cabling, new grey joining existing white. Did not notice if it was 2.5 or 1.5mm cable. It goes up into the loft. Again, I guess it does not break any regs, but how hard would it have been to run the first leg as one new piece?

Am I being to fussy or is this considered an acceptable standard of work?

One sparky said to me about the other, that he is an NICEIC Inspector. Not sure what that actually means. Is it just that he is the one who signs of the company jobs, or does he do work directly for NICIEC?

 

[Telecoms_man]

This is what they installed today. I would not have the cheek to do it that badly.

 

[Lister1987]

Hi,

Thank you for your replies so far.

Yes it is a commercial installation. A refurbishment and building extension. Refurbished parts are being re-wired and a new fire alarm being installed. It is FP200 cable, checked today.

First picture shows new cables (grey) coming through a bulkhead wall between two loft areas. Hole could have been drilled at floor level. No attempt seems to have been taken to run the cables neatly or avoid other services. Their own 240V and 24V fire alarm cables run together. White cables clipped to floor are existing intruder alarm cables.

The cables are just run as quickly and as easily as possible in the loft area, over existing walkboards, rather than under, causing both trip hazard and potential damage to the cables when they get walked on or loft gets filled with junk. Many are run diagonally around the loft. No sign of a single cable clip anywhere on the T&E. Has made my work so much harder, trying to find ways to route my cables to avoid the mains stuff. A little more care by them would have made their job look so much neater.

Second photo shows the new fire panel. FP200 cable is crossing the T&E, running in the same trunking.

Picture 3 shows an earth bar in the trunking. At least it has one screw in it. Don't know where the end of the cable goes, I'm guessing water or gas. both are easily accessible, so whilst this would not break any regs, it would be neater to renew the full length.

Picture 4 is a joint in the cabling, new grey joining existing white. Did not notice if it was 2.5 or 1.5mm cable. It goes up into the loft. Again, I guess it does not break any regs, but how hard would it have been to run the first leg as one new piece?

Am I being to fussy or is this considered an acceptable standard of work?

One sparky said to me about the other, that he is an NICEIC Inspector. Not sure what that actually means. Is it just that he is the one who signs of the company jobs, or does he do work directly for NICIEC?

The T&E into the keyswitch for the alarm should also be fire rated, not straight T&E, pretty certain the standard is explicit about this as it forms part of the alarm system itself and so should be fire rated.