Newbie with regs & testing questions

[waitees]

Hi all good website with tech answers.

I have just registered with the NICEIC just awaiting a date to come and inspect my work. I have a few questions regarding a couple of new jobs.

1 - the old bonding for the gas is just below the cu as the gas pipe runs from the meter outside the front door threw the wall and then along the wall to under the stairs, the question is will i have to drill a new hole threw the wall for the bonding then make sure its attached 600mm away for consumer side or will the orignal bonding will be ok , if not do i have to reseal the hole afterwards in any particuar way ?

2 - i have to install a new circuit to upstairs lights, the only way is to the top of the stairs then threw the bedroom then in the cupboard where the immersion heater is and clip to the wall to the loft, is this aloud ?

3- I have a kewtech kt64 when i do rcd testing i do it at o and 180 degress at 1 and 5 times, could some one tell me which reading is recorded on the certifcate ? is it the highest reading ?

Any info would a great help.

Thanks Paul

 

[T&Earth]

Hi Paul

having had my assessment recently by NAPIT you will need to read up on the 17th as I'm sure they will ask you questions, I was asked loads!!

with regard to your questions first I'm not an expert, but there are loads on this site

1. I would run new main bonding as you have said within 600mm seal hole with silicone
2. Suface mounting cables is fine
3. with regard RCD record 1x and if required for additional protection 5x within 40ms I always record both hope this helpsGOOD luke

STEVE

 

[waitees]

hi steve thanks fo response.

with the rcd testing on the cert it has 1 and 5 to put in as a result do i use 0 degrees or 180 as the result for both 1 and 5 times ?

also clipping in the cupboard is it still ok that its in a cupboard where heat is produced from the immersion heater ?

thanks again Paul

 

[Mark_Burgess]

Hi Paul,

Put the highest RCD values on the cert.

I would have thought if you show your cable calculations of ambient temp and insulation de-rating factor etc, that then allows the cable to be suitable it will show the assessor you have thought about it and not just thrown the cable in.

 

[johnr]

hi, the highest reading on the rcd test is recorded, and i also do a ramp test and at the end do a functional test.
when you say clip cable in a cupboard with a heater...is the cable for the supply to the heater? I would terminate the t&e into the sfcu as it enters the cupboard, and then clip the heat resistant flex round to the heater.

 

[acat]

As above and you are looking at around 3 to 3 and a half hours for your assessment know safe isolating procedure and testing backwards no only testing but expected readings and what could be wrong if you dont get the expected readings.

As for the rest if you dont know it be honest but know where to find it dont waffle they will spot that a mile away. Tea and biccies goes down well creates a good atmosphere and all work should be neat and tidy with no exposed metal in CU etc.

Good luck with your assessment and anything you are not sure of ASK we hall all been through it



Chris

 

[waitees]

thanks for the response the cable is supplying the lights upstairs and has to go via the cupboard with the immersion heater, its not connected to it in any way just passing threw, was just worried about heat factors on the cable.

forgot to mention 2 other things, the install has an alarm the fcu is located right next to the cu for the alarm so the cable is only about 20 cm long and the alarm right above it, it has a 3 amp fuse in the fcu is it ok to put this on a 6 amp mcb as it has a very low output it is on a 32amp breaker at the moment sharing with one of the rings which i have been told is not good.

thanks for all the responses !

 

[johnr]

hi again, run the cable up in trunking as far away from the heater as poss, (if the heater is set back in the cupboard run the trunking up against the inside of the door frame.
if there is a spare way in the cu, then yes put the alarm on a 6A mcb (preferably on non protected side if there is one) as you have said the fcu has a 3A fuse and this then complies with discrimination.
Hope this helps

 

[JUD]

thanks for the response the cable is supplying the lights upstairs and has to go via the cupboard with the immersion heater, its not connected to it in any way just passing threw, was just worried about heat factors on the cable.

What size cable are you using for the lighting circuit?

If you're using 1.5/1.0mm² T & E I wouldn't worry too much as this could, in practice, be de-rated by as much as 70% for a 6A lighting circuit as it carries 20A (Method C). I can't see you having to de-rate that much unless it is running completely surrounded by insulation anywhere.

 

[waitees]

The cable i was going to use was 1.0mm twin and earth as its only supplying 4 lights, one being on extra low voltage for the bathroom. The cable runs up the inside of the door frame and the immersion is set back about a ft and a half away for the cable. The cable is clipped above insulation in the loft but under loft flooring. I have tried looking in the books for a figure that may be lost in the cupboard, any help would be much appriciated !

 

[JUD]

You really need to know what the ambient temperature is likely to be inside the cupboard and then you can work out if you need to de-rate the cable or not. A 1.0mm² cable still carries 15.5A (Method C) and with an ambient temp of 60° and de-rated by 50% (Table 4B1 page 267 BS 7671) will still carry 7.75A. As you're only supplying 4 lights, you should be ok with 1.0mm².

You said your cable runs under the loft floor. Is it 50mm below the floorboards?? 522.6.5 page 100 BS 7671