Then there's no code.
If it were singles through the conduit, there is an argument that it's equivalent to class I so needs to be earthed/bonded (as exposed conductive part), but pvc/pvc is double insulated, so it's equivalent to class II and earth/bonding isn't required.
If it's t&e then that's fine, no code of course, but several years ago twin was extensively used when moving from household conduit to pvc/pvc.
That presents a fairly wide issue where lighting circuits especially have no CPC/earth,
As the op stated twin rather than t&e and the age of the...
I may be missing something here, but you say they have used twin, so there is no earth at any switch or socket - is that correct?
(Other than ones where the conduit is continuous end to end)
If so that's technically a C2 - but I would consider it C1 and wouldn't be comfortable leaving the...
Your calculation is correct (ish).
Think of it this way, if each current was 100A at 230V you could calculate 100 x 230 (23kVA) x 3 = 69kVA
OR
100 x 400 x sqrt(3) = 69kVA
OR
100A (as measured on phase 1) x 230V (as measured on phase 1)
Plus
100A (as measured on phase 2) x 230V (as measured on...
That's not an issue with the fixed wiring, the heat damage is not located near the fixed wiring connectors.
It could be an issue with the plug wiring, a bad connection in the plug could cause heat to travel down the plug connection into the socket itself. However, this would usually be...
I have been asked to wire an Air Source Heat Pump for a Koi pond - no biggie from the electrical point of view.
However, I thought I would check up on the required settings, and plumbing - just in case there is anything special for this application, so came across this video:
I just...
I kind of share the same concerns, when an RCD is present as additional protection then I am quite comfortable, but like in this case - the rcd is fault protection (411.4.204/411.5.2 sort of thing) just having this one device just doesn't feel enough.
By the regulations of course it is...
TBH I don't think that's too bad an overview, sure we can all find issue with some of the wording, for example "an RCD protects against an electrical shock" - no, you still get a shock, it just limits the time to reduce the potential consequences; and of course the "fail or pass" of an EICR...
That is one possible scenario, however it's not a likely one, it is fairly possible in remote areas, it can only occur if either the bonding isn't in place or all services are plastic, and even then only if the broken PEN is between the property and the last earh rod (as PME)
In general...
Keep everything in the greenhouse class 2 and you don't need to bother.
The light sounds class 2 anyway - it's just a matter of making sure you don't have anything class 1 used.
Yes that's fine.
Remember to ensure that the earth/CPC and armour of the cable is correctly earthed at the source end, and is NOT connected to the rod, or anything that can be touched at the TT end.
Yes, but if the earth from the substation was connected via the CPC to the metal, or to other exposed conductive parts if you contacted then you would have the 200V.
That's why if you TT anything you must ensure that the "real earth" from the substation cannot be touched at the same time.
If...
There are actually a whole host of considerations behind the need to/to not bond , so it pays to understand these in order to understand why things are done the way they are.
So, let's imagine your house has its supply from a substation 100m away.
Ignore the line and neutral, when you...
You could TT the whole installation, in which case the rod at the PME must be disconnected from the PME and used for the TT
But there could be other issues if the overall site is changed to TT, for example you may need to change to dp rcds/rcbos etc.
You could just change the one circuit to...
It doesn't change what needs to be done - determine if it is actually electrically connected to the earth, if it is apply the correct sized bonding conductor or change this circuit to TT.
However, I suggest you check the BBB in part 2 and look at the definitions, ECP is a conductor which...
Absolutely not!
If the metalwork has a good/reasonable connection to the earth then in the event of a broken PEN the local neutral connection will be connected to the substation star point by virtue of:
The neutral-earth bond in the head then
This earth/CPC connection to the earth mass then
The...
With commercial, it is quite common to perform fairly small samples, the point is unlike domestic they will often have someone responsible for the planning of the scope of work. This person will often phase the inspection work over several years.
In simple terms, main supply and building A...
No, but I would actually use a proper ip rated connector, in addition, don't cut the cable as it goes into the plug's strain relief, actually cut it within the plug itself - this could add several mm to the available length.
Does the plug have an earth/cpc connection?
If it is just the...
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