3p variable RCD

[scrag]

Hi Guys. Got to look at a job on Tuesday and have a couple of questions.

1. Artificial ski ramp built into a hill. The top of the ramp is constructed with ply and timber joists supported by steel scaffold which is also acts as handrail. There is a small lockable store with lighting and power. The ramp is not part of the the main building which is on a PME supply. The scaffold has been bonded via the cpc. My question is, shall I leave it or make it into a TT.

2. There is also a 3p variable RCD controlling the ski lift on a different part of the site which requires testing. Not sure how to test the times without a neutral being present. Any advice would be most appreciated.

 

[Andy™]

TNCS with exposed handrail is just asking for someone to be killed...

where is the RCD located? there should be a neutral somewhere close to it?

 

[scrag]

Yes the hand rail is not good and will look at the options.

There are neutrals in the enclosure but will I get realistic values by using another neutral on a different circuit. I will be taking another test kit with me on Tuesday that I hope will allow me to do RCD tripping times without a neutral. I am just concerned that the values I get will be a true reflection of a fault occuring as I have not done this sort of arangement before

 

[Zeespark]

Are you proposing sharing a neutral? Last time I checked it was illegal.

AndyGuinness

 

[spinlondon]

Not Illegal.

I think he's talking about borrowing the neutral for testing purposes only.

 

[Andy™]

Yes the hand rail is not good and will look at the options.There are neutrals in the enclosure but will I get realistic values by using another neutral on a different circuit. I will be taking another test kit with me on Tuesday that I hope will allow me to do RCD tripping times without a neutral. I am just concerned that the values I get will be a true reflection of a fault occuring as I have not done this sort of arangement before

providing the neutral you use isnt on another RCD'd circuit, or both RCD's may trip.

 

[scrag]

just borrowing the neutral to test but will be using a kit that does not require a neutral. I will make a comparison between the two test kits and see what the difference is just out of curiousity