1st install job advice please

[rob675]

Hi all,new on here just after some advice.I have my first job starting at the end of the week,i have been to look at it it is installing 4 downlighters and a extractor fan in a repositioned ensuite.I am planning to extend the original lighting circuit to use for the lights/extractor-i take it this wouldnt be classed as a new circuit? also as its supplying a bathroom im assuming it has to be rcd protected?if so again im assuming the cable in partition wall/under floor and ceiling wont need mechanical protection.The cu is directly below this room so not a long run i take it 1mm t&e is ok?
As im not registered to a scheme yet i have had to go down the building note route,they have said i can do the work-test & certify they will just come round and check it before they sign it off,does anyone have any experiance of this?I know theres allot of ? just want to get things right first time.

 

[alanl]

No, 1mm is not good enough for an extractor fan.
1.5mm for all power circuits - Table 52.3

 

[Octopus]

Extractor fan - isolation and fusing down?
Bathroom - notifiable
What are you planning to directly connect to the CU?
RCD's definitely
Bonding?

 

[rob675]

No bonding needed if all circuits rcd protected??

 

[Stuuk1]

No bonding needed if all circuits rcd protected??

Just make sure gas and water are bonded, ensure continuity through all pipework, extensions usually contain plastic fittings..

 

[telectrix]

and you'll find that the LABC fee is as much as you are charging to do the job. so a £250 install becomes £500 and you're blown out by a Electrical Trainee scam member.

 

[i=p/u]

Use 1mm 3c for smokes, think it means other than lighting

- - - Updated - - -

Ie power

 

[telectrix]

No, 1mm is not good enough for an extractor fan.
1.5mm for all power circuits - Table 52.3

disagree there. fo a fan 3 core 1.0mm is normally used.

 

[HandySparks]

....ensure continuity through all pipework, extensions usually contain plastic fittings..

If, because of the plastic fittings, the pipework is not an extraneous conductive part, then no need to bond.

 

[alanl]

It may be normally used, and may well be safe to use, but Table 52.3 says 'power circuits' minimum of 1.5mm conductor, and 'lighting circuits' of 1mm.

Little used, and passed by by most, but it is in there.
I have done smokes before in 3core 1mm, maybe this should be uprated to 1.5mm in future, as a circuit supplying only smoke alarms is certainly not a lighting circuit.

 

[micknew]

It may be normally used, and may well be safe to use, but Table 52.3 says 'power circuits' minimum of 1.5mm conductor, and 'lighting circuits' of 1mm.

Little used, and passed by by most, but it is in there.
I have done smokes before in 3core 1mm, maybe this should be uprated to 1.5mm in future, as a circuit supplying only smoke alarms is certainly not a lighting circuit.

God help us.

 

[Andy78]

It may be normally used, and may well be safe to use, but Table 52.3 says 'power circuits' minimum of 1.5mm conductor, and 'lighting circuits' of 1mm.

Little used, and passed by by most, but it is in there.
I have done smokes before in 3core 1mm, maybe this should be uprated to 1.5mm in future, as a circuit supplying only smoke alarms is certainly not a lighting circuit.

The difference lies in how you phrased it. Power circuits and lighting circuits.
A bathroom fan is a branch of a lighting circuit, appropriately specced for the cable used in that circuit.
A power circuit can utilise 13A fuses, either in plug tops or FCUs, requiring a 16A MCB, hence the minimum requirement in cable size under most desirable installation method.

 

[alanl]

God help us.

Come on then, read the Table, and tell us your interpretation of it.

 

[Octopus]

Come on then, read the Table, and tell us your interpretation of it.

Well..... do you connect your fans to RFC's? or lighting circuits?

 

[micknew]

Come on then, read the Table, and tell us your interpretation of it.

Hi alani, the average bathroom fan (15W) consumes about 0.06A.
There is no way I would feel you must use 1.5mm.