PIR unsatisfactoty

[Shift]

Decided to get PIR done and correct any faults found. Most faults found I can do myself(before anyone says I can't do the work myself I'm 16th edition qualified and will inform local building control before starting and get it certified after completion,anyone know how much this costs).First thing I need advice on is, I have one 3 way fuse box in the cellar near the meter and the main 8 way fuse box at the cellar top. The 3 way supplies one ring,two radial and one light circuit,the ring and radials are downstairs and the spark said should be protected by a RCD,the ring powers 3 sockets in the lounge (tv equipment/stereo/lamps etc) and is very unlikely to be used for outdoor equipment, one radial is the cellar and the other radial is for a socket in the hallway, which is the best option to protect these circuits. I thought either a 100a dp 63a rcd 30ma split load(4+4 is the smallest I can find) or a 3 way 63a 30ma RCD unit
I'm going to replace the 8 way fuse box with a 100a 80a 30ma rcd 10 or 12 way split load consumer unit, the RCD will protect the dining room (tv equipment /computer) and kitchen ring (fridge freezer/dish/cloth washing machines) plus the 9.5kw shower,am I missing any thing. Obviously the the cooker the upstairs ring and lighting will be on the mcb side.

 

[RF Lighting]

You could install a small 4 way board with a couple of RCBOs fitted in it rather than having to fit a 4+4 way split load CU. (I bet JohnD agrees too ). Or would it be possible to reroute or extend the circuits to the larger CU at the top of the cellar stairs, doing away with the need to fit a CU downstairs at all.

 

[Shift]

I thought about extending the circuits but I don't like using junction boxes but the more I think about it your right it's the best option, thanks. Do you think it would be ok to use the junction box to spur off to the 2 radials.

 

[Adam_151]

Nothing wrong with junction boxes as long as they are installed properly and are accessable for inspection, and correctly rated good quality ones are used (I like MK, I've used cheaper ones, and the screwheads deform before I can get it quite as tight as I'd like, I usually eventually get it there with difficultly, but if I need to slacken them off to put more cables in a new JB would be needed, MK's ones (30A ones at least) don't just have a single screw per terminal, they have 3 or 4 [ceiling rose style]))
At about 50p dearer, I'll use the MK ones, lot less fecking around

 

[plugwash]

MK ones may be nice if installing from scratch with cable thats just big enough and no bigger but if you have an oversized cable they become difficult or impossible to work with.

when i was less good at cable size identification i used some spare 2.5mm and 4mm on our lighting circuit) they will not accomodate it and at least thier lighting sized ones have only two terminals per position and will only take one 2.5mm (and won't take 4mm at all) in each of those terminals.

 

[JohnD]

You could install a small 4 way board with a couple of RCBOs fitted in it rather than having to fit a 4+4 way split load CU. (I bet JohnD agrees too ). ...

It's true, I love RCBOs, especially MEM ones. I would probably also fit a larger CU than you think you need, you only pay a little extra for the fresh air and a plastic box to keep it in, and it will be handy when something crops up you hadn't thought of.

But to be fair, if you can extend the circuits and only have 1 CU in the property instead of two, that would be a neater design. The distance does not seem to justify a sub-main or split supply, and users are liable to turn off the main switch in the top CU and incorrectly think the entire installation is isolated and safe.

Also consider crimped joints as a neat and permanent alternative to JBs. Though I have used the rectangular MK 30-amp JBs and been very happy with them (don't like the cheaper round JBs though, except for lighting). Never used anything above 30A except for Henleys and similar.

 

[Shift]

Something else I forgot to ask advice about, the spark doing the PIR commented on a number of sockets still mounted in skirting boards. He said in the report that they should have metal back boxes but didn't say they should be moved onto the wall, can anybody clarify as I cant find anything in the regs and as I'm moving don't wont to do any unecesary work. One last thing in my bathroom I have 6x12v downlighters which are ip44 and 3 of them are in zone 2, the spark said they need to be ip65, is he right because in the regs as far as I can make it it says ip*4.

 

[ban-all-sheds]

Another option of course for extending cables in this situation is to use DIN rail mounted terminals in a small enclosure.

 

[dingbat]

Bryan, IPX4 (protection against splashing from any direction) is what is required.

In IP65 the '6' is irrelevant, as it applies to mechanical protection from dust and the 5 rating for liquid protection would only apply if the lights were subjected to water jets. Unless you're in the habit of pointing your shower directly at the lights this is clearly over the top.

 

[Shift]

Just been counting up how many sockets in the skirting and there is 8 all together,more than I thought. Anyone have any info on sockets in skirting boards !! because I cant find any and I really don't want to move 8 of them if I can avoid it.
In my job when ever I've had to extend cables I solder the wires together and cover the joint with heat shrink, is this ok for house wiring.
Lastly I plan on putting the kitchen ring(fridge freezer/dish washer/washing machine), the dinning room ring (tv/computer),the lounge ring(tv/stereo) this ring also includes the hallway socket. Obviously the fridge freezers on all the time and sometimes the dish and clothes washers will be on at the same time. I've read that too many appliances may cause rcd tripping is this correct and what can I do to avoid it.

 

[JohnD]

Washing machines are one of the things most likely to have an earth leakage; and a freezer is one of the things you least want to go off when you aren't in; so if you can see any way of not having them on the same RCD, that will be an advantage. Some people like to have a dedicated radial circuit just for the freezer. If you are reconfiguring your Consumer Unit this might be a possibility for you. Have a look at a big one and consider RCBOs; although they tend to retail at about £30 you can often pick up boxed overstock at half that.

Cookers, microwaves and immersion heaters are some other things particularly likely to have earth leakages.

You aren't compelled to move your sockets; but at skirting level they are often cracked and broken when they get knocked by hoovers, furniture or boots. If you do move them, the recommended minimum height is now 450mm (this is actually because they are easier for disabled people to reach, and you aren't obliged to do it in an existing house; though if you want to rent or resell it some people will prefer it. It is also easier for the weary old DIYer to reach when he has a bad back, leg or large stomach

If you join the wires permanently, you don't need a junction box. crimping or soldering are two permanent methods. Heatshrink is good. If they aren't in an enclosure they will also need something equivalent to the cable sheath round them, oval plastic conduit should be suitable. I haven't seen heatshrink that big but I presume it is available.

 

[Shift]

What about leaving the kitchen on the MCB side and fitting a RCd socket to the socket near the back door, but then what would be the point of having the rest of the ground floor protected by RCD and the area with water and electric not. As you suggested Johnd I think the best bet would be to provide the fridge freezer with it's own supply.
By the way you can get heat shrink up to 100mm.

 

[Adam_151]

Soldering is an acceptable way of joining cables, but be sure to do a good job at making the joint, see here for some pointers: http://www.theiet.org/forums/forum/messageview.cfm?catid=205&threadid=10161&highlight_key=y

Crimping would be a lot faster tho