Screw terminal/JB accessibility

[markocosic]

Hello,


Wiring regs say screwed connections must be accessible. On a scale of 1-victor meldrew, how mean and grumpy would an inspector have to be to fail the following please...


Existing junction boxes under floorboards:

I've got an existing installation where there are 30A junction boxes (round things with lids) hanging in the floor-ceiling void, for both lighting and ring main circuits.

"Finishing the job" and screwing these to the joists/clipping the cables is no problem. Accessing these for inspection takes about 10 minutes: lift the edge of the carpet and remove one (loose and marked) floorboard (plank, not chipboard) 2nd from the edge of the room and you can see the lot. No tools needed; other than the screwdriver to whip the covers off the JBs.

I'd argue that its just as accessible as any socket behind a fridge/washing machine. Will it fail an inspection? Is it "grandafthered in" as an existing installation, even where I change the faceplates and the consumer unit?


Terminal blocks behind plateswitches

You know the score... Somebody has cut the cable that's buried in plaster short and added 75 mm extensions with terminal blocks. Fugly but effective. Pre-existing. Accessible with a screwdriver. Legal?


Terminal block ring main extensions

Extending a ring main using terminal blocks behind faceplates. (replace a single in a bedroom with two doubles) Also fugly, but provided that they're 30A rated/the earth impedances check out (it's <35m^2l tiny house/circuit) is this legal? Not pre-existing/would be a modification. Accessible with a screwdriver.


Cheers,


--
Marko

 

[Scoby_Beasley]

Existing junction boxes under floorboards:

No problem with that as long as a note / schematic drawing of their location(s) is available next to the CU. Other option is change for 30A maintenance free (mf) jb's.

Terminal blocks behind plateswitches

Should be OK but Wago or Line connectors would be mf.

Terminal block ring main extensions

Would definitely prefer Wago or Line connectors in this situation if in back boxes.

 

[PrenticeBoyofDerry]

Existing junction boxes under floorboards:

As the installation is existing, that would be no reason to fail an inspection providing it is safe. You improved the set up by clipping cables and mounting boxes, so I'd expect browny points for that!

Terminal blocks behind plateswitches
Terminal block ring main extensions

The terminal blocks are within enclosure and rated correctly for circuit, continuity and polarity checked and the conductors are correctly identified.
So that's fine.
If the installation is of old colour cores (T&E=red/black and 3c&E=red/blue/yellow) and the alterations are of new core colours (brown/blue and brown/blue/grey)
Then a warning notice should be placed at the consumer unit, stating two versions of BS7671 wiring colours are present on the installation

Untitled

• PrenticeBoyofDerry
• 14 Oct 2011
• 4

On the schedules and certificate, document/remark on the above issues.