Visual fault number 2

[MDJ]

Okay how many faults here?

 

[Baker1988]

I can only see a few faults (1) the flex going into the heater is showing the inside cores so only has basic protection. (2) it seems as though one cable can be isolated but the other one can not be(don't understand why there is 2 cables)

 

[MDJ]

both cables can be isolated if you look again, it is just the way the installation method comes across, how about the flexible conduits are not secured to the wall to add another? the second supply for a fan circuit and on peak, controlled by a time clock so the heaters can be controlled via a fan blower during the day if needed.

 

[Resu]

Difficult to tell and maybe not so much faults but oversized switch and conduits unnecessarily long?

 

[Paul.M]

I cant make it out in the picture Mike but is there a CPC in the top piece of conduit/copex? If not there should be.

 

[MDJ]

yeah there is one, the main problem is the cable has no mechanical protection at either end, the flexies at the wall end are just pushed in and not glued, it is in a school dining hall which makes it worse, the flexies are too long, no saddles at all, and the guard is actually come away from the wall too and not secure, the cable to the heater is a 4mm2 cable, the heater is 4.0kw so fine there, however it is connected the other end to a 40 amp c rated mcb, there are other issues with this as well which cannot be seen from this picture, I will try to get another up to show more

 

[Paul.M]

I've got some right horror pictures over the past 2 months, got to punch them up in here. Give me time, I'm really busy at the moment with the local school electrical inspector on my back.

 

[telectrix]

I've got some right horror pictures over the past 2 months, got to punch them up in here. Give me time, I'm really busy at the moment with the local school electrical inspector on my back.

that'll teach you to bend down to pick the soap up.

 

[Ewan D]

Hi- I'm looking at this on iPhone so I reckon I can't see the whole picture too well, but would that cage be metal and would it need earthing as it would be classed extraneous to the install?
I will look at the picture on PC tomorrow.
Cheers, Ewan

 

[telectrix]

Hi- I'm looking at this on iPhone so I reckon I can't see the whole picture too well, but would that cage be metal and would it need earthing as it would be classed extraneous to the install?
I will look at the picture on PC tomorrow.
Cheers, Ewan

gawd 'elp us.

 

[Ewan D]

Well would it? And maybe you could explain why it would be wrong to assume it could never become live? Seeing as that conduit could easily be kicked out. This is in the trainee section of this website, perhaps a little more insight into my way of thinking might be advantageous.
If its wrong, explain why I would be wrong in thinking a metal cage could ever become live should those conductors ever get ripped out. That would help me a lot more.

Thanks

 

[telectrix]

OK. forget about the cage becoming live. it's a fallacy to think that way. the reason that you bond extraneous metal is to keep it at the same potential as exposed conductive parts. now, incoming metal pipes are in the ground, and so introduce an earth potential ( 0V). when and if an exposed conductive part becomes live during a fault condition, then there will be the supply voltage (230V) on it and 0V on the extraneous. if a person were to be in contact with both points, he/she would be electrocuted. the reason we bond is so that, during a fault condition, the bonded metal will rise to mains potential, so there is then no potential difference between the supply and the extraneous metal. in other words equipotential.

 

[Ewan D]

Ahhh! This is the meat I'm after! Thanks for the (really quick) response.