Are there SANS regulations regarding this topic
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Morning all, any thoughts on the topic
The use of steel conduit was written into Sans in December 2021 but then removed again the same month and never returned.
I have lost the pictures of steel conduit that was used in some installations on the Natal coast. The corrosion build up in the pipes after 3 years we’re so bad that it cut into the insulation of the PV wire causing the wires to burn. The build up was so bad the the wires could not be pulled from the conduits.
When we don’t use the newer twin PV cable (that does not require any conduit at all), we use normal PVC conduit or Trunking. On bigger commercial installs we use metal wire ways like the P2000 with lids and bigger metal trunking with lids for bigger installs with more strings.
I remember @warwickchapman posting about this issue on some platform a year or two ago, maybe he can share his ideas as well.
I know that steel conduit is not a requirement and can be used if you choose, but I’ll stay away from it in coastal areas.
Slightly off topic, will using steel conduit be an advantage or disadvantage for earthing and lightning protection?
Asking because lightning is a massive factor where I live.
Recently a few years old pex water pipe, surfaced mounted on a west facing wall, started to “disintegrated” as it was never painted. New pipe same place, is now painted.
That and other observations of things outside in the sun made me wonder how long PVC conduit / trunking / newer twin PV cable can last if it is exposed to the sun?
@JacoDeJongh , thanks for clearing up the Sans regulations
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Agree, Normally we dont install PVC outside on the roof, if we do, we normally paint. We also advise the client to paint trunkings on the wall the same color as the walls. Leaving it open will lead to problems a few years in, after the sun burns the trunking away completely, it must start burning away the insulation on the wires, another year or two.
We never expose twin wire to the sun. In some kind of wireway into the roof cavity, from there exposed up to the installation area and then in trunking on the wall. I love that wire, saves a lot of time, no conduits or trunking needs to be installed in the ceiling.
I hope the installer who wired the panels on my roof did what you posted. 
When the solar system is moved the wires from the roof must be re-routed to come down to the front.
With newfound knowledge, can make sure as much is out of the sun, and where in trunking, that it is painted.
In a single story house always go through the attic, unfortunately in a double story house, have to do some outside conduit work, and, yes, I do advise clients to have conduit painted the same color as the house.
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There is a trunking screwed to the top of all your panel frames, when we added panels for you we used the existing trunking. Cant remember if it was painted though.
No worries.
Being “early days” back then compared to what we all have read, heard and learnt the last couple of years, when it is moved (again) all of that knowledge should be applied going forward.
Just happy to learn no steel enclosure needed, cause I would have “fought tooth and nail” against that, regulations or te not.
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Do you have a suggestion of where this is available. It’s not a widely available cable and I also would rather use this. Much easier.
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I presume the steel conduit here refers to galvanised steel tubing.
It is primarily used for indoor industrial installations due to it’s strength.
Plastic trunking/conduit which is used domestically for these applications is way cheaper but is often poorly installed.
Pretty much the only place metal conduit is required is where passing through walls, ceilings, etc:
6.4.8.1 If wiring has to pass right through a building element such as a floor,
a wall, a partition, or a ceiling, conductors and busbars shall be in a non-
flammable enclosure or wireway.
Does not have to be metal, but can’t be PVC, at least.
Typically, external walls will also be a fire break, so this will also apply when bringing wires into the house:
6.4.8.2 If the building element is a fire break, the space around
a) a cable,
b) a wireway, or
c) the wiring in a wireway, if the internal cross-sectional area of the wireway
exceeds 13 000 mm2,
shall be completely filled with non-flammable material over the full thickness
of the building element.
I suppose it would be open to interpretation if the wires go between building elements (between roof and wall, for example). I have seen it done both ways.
And here’s a classic industrial application: https://images.app.goo.gl/15MJQ4YBbqk6NGJf9