Large number of 13A sockets in a steel building: Design considerations.

[Mark42]

Job done.

Pic of the shed shows what I was on about – I wanted to run an RFC all around the perimeter.

But OK, I’ve listened, and changed my mind. I installed it as two separate radials, on two 20A breakers, rather than as a single ring on one 20A.

I believe it's electrically not as sound as my ring proposal (the CSA is lower), but I agree more ‘standard’. An example of where strict compliance with regulations is actually worse electrical design than ‘breaking’ the rules.

Also a pic of using SY for the sockets but without the correct SY glands, designed, I believe, primarily for where EM screening is specified.

Unravel the screen, twist, sleeve g/y, then shrink-fit the lot. Outer sheath ends in a normal cable gland. Is this OK? BTW, the holes in the back of the metal boxes will be sealed to keep insects out. Not fitted the accessories yet, and though I’d better consult this wise oracle before proceeding …

Thanks, Mark.

 

[mogga]

Im assuming this may be for FLT batteries iv seen them done with busbar a few times dependant on the load

Only concern I may have would be the "wosk area" and any welding ect in the presence of battery fumes ect

 

[Silly Sausage]

Massively envious of your 'shed'!

 

[Mark42]

Im assuming this may be for FLT batteries iv seen them done with busbar a few times dependant on the load

Only concern I may have would be the "work area" and any welding ect in the presence of battery fumes ect

I was asked this before.

Naa, they are only for ordinary batteries: cars, lawnmower, motorbike, children’s quads, that sort of thing. Nothing big. And only little ‘Accumate’ maintenance chargers to stop the batteries self-discharging when left for a long time.

No hydrogen gassing off to speak of.

Massively envious of your 'shed'!

Thanks Archy. I like my shed too. The only way I can afford admittedly ridiculous projects like this is by doing everything myself. Which is one reason I’m on here asking questions …

Oh, and the other thing is to buy nearly everything on EBay, and to throw away your Tv.

 

[Silly Sausage]

........... is by doing everything myself. Which is one reason I’m on here asking questions …

Absolutely, go for it! (as long as you comply and get by the Notification Police (sarcasm can be taken as read there))

Oh, and the other thing is to buy nearly everything on EBay, and to throw away your Tv.

Ebay is my friend too. Need to get unhooked from trawling Electricians Forum next!

ghjdjuyhdtyjgutdrse6vbaew

 

[UKMeterman]

Hi,
Don't lightly solder where screw terminals are concerned, the screw pressure over time will cause the solder to cold flow. Have a look at farnell part number 1121755 for the correct item to use.

 

[Mark42]

Hi,
Don't lightly solder where screw terminals are concerned, the screw pressure over time will cause the solder to cold flow. Have a look at farnell part number 1121755 for the correct item to use.

Thanks - Very good advice about the cold flow.

I already ordered some 6mm (yellow) twin-entry ferrules, which two x 2.5mm SY cores fit nicely, but once crimped they won't go into the terminals!

The Farnell site is not clear on the spec of 1121755. Is that TWO x 2.5mm cables or 2.5mm TOTAL CSA?

I don't want to remove strands if it can at all be avoided.

 

[Silly Sausage]

Don't cut any strands!
Try the next size down.

 

[malcolmsanford]

Most likely me Mark, but I see a load of yellow and green cables there but not a brown in sight. I see where you have heat shrank the braid ok, I see a couple of Blues and then 4 what look like CPC coloured cables ..........

 

[johnboy6083]

malc, there is 2x brown, but it looks like a black in the flash. 2x neutrals, 2 x CPC and 2x braiding

 

[malcolmsanford]

Lol I still can't see them, but take your word for it mate

 

[UKMeterman]

It is designed for 2*2.5mm to sit side by side.

 

[Mark42]

Thanks, John! Yes, Malcolm it is you: I reckon you've had too much desert sun Or you need a new monitor ...

It is pretty poor sleeving, from TLC. All a bit stuck-together and floppy, I don't like it much. I prefer to shrink-fit cable ID markers, but it's a waste of money for all that lot, which no one will ever see again.

 

[Mark42]

It is designed for 2*2.5mm to sit side by side.

OK. Ordered on-line just now!

Malcolm, joking apart, this is a massively interesting psychological effect, especially relevant when quality-assuring one's own work in many trades. Can you really not see those two brown cables? They are quite clear and absolutely in your face!

I can't remember what the effect is called, but I know psychologists have studied it. There is a book by Prof Richard Wiseman called ‘Paranormality: Why we see what isn't there’ which touches on it. Something about the 'gorilla in the room'.

Subjects are shown a video of people arguing in the street or something, but no one, when debriefed afterwards, remembers seeing the guy in a gorilla suit walking by. But he's there and absolutely clear. I reviewed the book on another forum where I annoy people:

On all things wondrous strange: ghosts, mediums, and rubber hands - Mark Ribbands - RichardDawkins.net

It’s all very fascinating.

 

[malcolmsanford]

To me they look like 2 conductors covered in black heat shrink/sleeving/neoprene, they don't look brown at all but there again I have old eyes