I think there might be confusion as @tom1414 tacked his question about a TN-C-S supply feeding TT installation onto an existing thread from 9 months ago about a different intake that probably was TN-S to begin with.
The dimmer is a bunch of electronics that corrupt the waveform of current passing through, likely to confuse the tester which is only expecting to see the sine wave of the mains through a length of copper wire. The actual figures will depend on exactly how the electronics in the dimmer behave...
If you are lucky you might be able to get an LED manufacturer / supplier to specify suitable fittings. If you can identify the existing fittings and/or installation positions, their applications engineer might be able to use their photometric data and CIBSE recommended levels to work it out exactly.
Those factors only apply where the cable is actually buried in the ground, as they account for how the surrounding soil carries the heat away from the cables.
Cable G doesn't seem to be the far end of any other cable in your drawing, so it is impossible to know how it was wired. However, the 3-gang box appears to be complete with an incoming feed from the panel which would be cable D. Cables A & E would go to the lights controlled by switches 1 & 3...
Much European wiring is carried out with NYM-J and similar, circular cable with solid cores and insulated earth, for anything that we would do with T&E. Where needed, you can switch to a more durable cable in the form of NYY, which can be handled in the same way as NYM and use the same...
It's fairly standard European practice, therefore many details are different to the UK because we're the odd ones out. Many of the fittings, cables etc that we use are unknown elsewhere and vice versa. Some things that we obsess over, e.g. cable derating factors, are often much simplified, and...
The reciprocals of resistances are conductances. G=1/R and R=1/G.
You can add and subtract conductances in parallel just like resistances in series.
With three conductances in parallel, the two known ones and the unknown, you can write:
G3 = Gtotal - G1 - G2.
And therefore the same will apply to...
Birkett's? John Birkett died last year IIRC, he had been running the shop(s) since 1960.
I too used to trek to the Edgware Road in my early teens to get parts to build projects. The excitement of coming home with a bag or bags of brand new components, clean and shiny, ready to begin work, was...
CPC are still around, part of the same group as Farnell these days. Their actual component range is limited although prices tend to be good on the stuff they do stock. Their strength is in electrical commodities like IEC cordsets, where their pricing and availability are very good for a...
The fact that the two halves of the fitting interact consistently, suggests that the wiring is jumbled up somehow and what should be two independent circuits of ballast, tube and starter are now interconnected. This can happen if both tube sockets at one end get detached from the body and put...
Not convinced by that conductor size either. The only solid 4mm² T+E I've ever heard of was aluminium, which was equivalent to 2.5 copper. I'm more inclined to believe it's 2.5. If so, this is a good demo for all the people who say '32A rings are dangerous because a break puts the full load onto...
Not only should, but must. All terminals need to be enclosed in a box, with the cable sheaths clamped or glanded so that no strain can be put on the connections even if the cable is tugged, and the said box fixed securely to the wall / cabinet. One does see a lot of floating inline connections...
This is important. On a TN-C system with a combined neutral / protective earth, a broken / high resistance conductor or connection can cause exposed metalwork to become live. You then have the question: What is live? The pipes with respect to the (earthed) neutral conductor, or the neutral...
That circuit in post 12 shows the control circuit working at 230V from L1 to neutral, whereas the OP says his customer's lift worked in the past without a neutral, which either means:
His control circuit is different and works at 400V
His panel contains a 400/230 transformer to achieve the same...
That MI seal is poking into the BESA box instead of being seated inside the gland screwed into its conduit entry. Advantage; you can see and get to the seal, offset against it hogging the space inside the box. The MI sheath is the earth but shouldn't be serving as the neutral; that practice was...
Not for many decades. We used to have a ceramic version often known by the brand name 'Scruit' although there were other brands. They can sometimes be found in very old wiring.
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc