Joint between 16mm &1.5mm!

[rolyberkin]

A donut of a builder has helpfully run a piece of swa two core 16mm to a small feature fountain fitted with 1.5mm flex, suggestions on best way to join, couldn’t get the 16mm in a wago!

 

[telectrix]

twist and tape. or source a IP rated SFCU.complete with a coffin box 60A connection block.

 

[shaun1]

Solder and heat shrink? Or DIN mounted terminals for each size with linking bars?

 

[ChrisElectrical88]

Giant adaptable box....

16mm in a 63A Connector, 10mm Between 63A Connector and 32A Connector, 6mm Between 32A Connector and 15A Connector, 2.5mm Between 15A and 5A Connector. 1.5mm Flex into the 5A Connector...

Dont forget to bootlace ferrel it into the 5A connector or it might look rough

 

[shaun1]

Whats it going into at the other end? In this situation, I can't see any technical reason why just putting one or 2 strands of the 16mm into a wago and cutting the others off. You would probably still have to put heatrink over the end to insulate the rest of them. Not sure how easy it would be to justify/sign off though.

 

[Pete999]

Whats it going into at the other end? In this situation, I can't see any technical reason why just putting one or 2 strands of the 16mm into a wago and cutting the others off. You would probably still have to put heatrink over the end to insulate the rest of them. Not sure how easy it would be to justify/sign off though.

I sincerely hope your reply was/is tongue in cheek shaun1.

 

[shaun1]

I sincerely hope your reply was/is tongue in cheek shaun1.

Well not entirely no. Obviously I would never consider cutting strands off a cable if it was correctly sized and carrying somewhere near its capacity. But in this case, presumably only a 1.5mm cable is required for CCC, and one strand of a 7 strand 16mm must be more than 1.5mm CSA, so what actual reason is there not to use it in this way providing ita suitibly protected for the 1.5mm?

 

[shaun1]

I think I would probably still be reluctant to actually do it, just because its so frowned upon (usually for good reason)...

 

[brains-lans]

Im DIY so don't shout at me, but I've done something very similar in the past for family who had knocked down an old garage and made garden bigger so wanted to have a light where the garage was.

16mm in to a resin bullet to 6mm SWA (using the screw down and snap bolt crimps) and then fed the 6mm in to a wiska 308 with swa gland and 1.5mm flex out on a compression before for a light.

Resin joint 450mm down, wiska box on a wooden post. MCB downrated to 6a at supply.

 

[Pete999]

Post deleted

 

[telectrix]

Im DIY so don't shout at me, but I've done something very similar in the past for family who had knocked down an old garage and made garden bigger so wanted to have a light where the garage was.

16mm in to a resin bullet to 6mm SWA (using the screw down and snap bolt crimps) and then fed the 6mm in to a wiska 308 with swa gland and 1.5mm flex out on a compression before for a light.

Resin joint 450mm down, wiska box on a wooden post. MCB downrated to 6a at supply.

sounds a decent soloution with beer in the brain.let me look agian tomorrow, or the next day, or next year, whenever i run out of beer, .....(that will be the day that i go to my grave/crem/hole in the garden/ whatever SWMBO wants. .

 

[brains-lans]

sounds a decent soloution with beer in the brain.let me look agian tomorrow, or the next day, or next year, whenever i run out of beer, .....(that will be the day that i go to my grave/crem/hole in the garden/ whatever SWMBO wants. .

Crimps did the 16 > 6 in spec, 6 fits in SWA small gland. seemed neatest way i could think of at the time i did it. Cant remember if i wago'd it or terminal strips but 6mm > 1.5mm flex is probably Wago compliant.

 

[Midwest]

Wot about using a reducing pin or lug.

 

[Rpa07]

Well not entirely no. Obviously I would never consider cutting strands off a cable if it was correctly sized and carrying somewhere near its capacity. But in this case, presumably only a 1.5mm cable is required for CCC, and one strand of a 7 strand 16mm must be more than 1.5mm CSA, so what actual reason is there not to use it in this way providing ita suitibly protected for the 1.5mm?

Trouble was Shaun, you were thinking it and then said it out loud!
I could lend you my tin hat but I basically never take it off!

 

[Richard Burns]

What is wrong with a bit of 60A terminal strip in a moulded box and a crimp on the flex.
Gland the SWA into the box and put the 16mm² in one side of the terminal block and the crimped flex in the other.

 

[Rpa07]

What is wrong with a bit of 60A terminal strip in a moulded box and a crimp on the flex.
Gland the SWA into the box and put the 16mm² in one side of the terminal block and the crimped flex in the other.

And you could place the ferruled end of the flex neatly in the strands of the 16, that would work and be cost effective.
Does it need fusing down or has it been done at the other end (upstream) of the 16mm?

 

[littlespark]

Question.
Why did the builder put in 16mm in the first place?
Tell him to dig it up and put in the right size.

or

Tie the cores to a jcb and gently pull it. It will either stretch the 16mm's down to a usable csa, or pull the cores out from within the armour. If that works, then tie a flex onto the other end and pull it in as the 16 comes out.
The "optimistic" badge is below, just about...……………....…. here!
Looks like a rainbow

 

[Midwest]

I sincerely hope your reply was/is tongue in cheek shaun1.

It is for a pond pump, not a outdoor hot tub, with Pampas grass and saunas

 

[rolyberkin]

Builder built the fountain and dug in the cable, customer had a load of 16mm 2 core left over from something else, they got their heads together and come up with what seemed like a plan!
Think will go with the connection strip or crimp ideas.

 

[Pete999]

It is for a pond pump, not a outdoor hot tub, with Pampas grass and saunas

It is for a pond pump, not a outdoor hot tub, with Pampas grass and saunas

So do you condone that form of butchery then? Should have had the right sized cable installed in the first place, and not left it to a builder,who probably thought "got some 10mm in the shed, I know I'll use that"

 

[rolyberkin]

And you could place the ferruled end of the flex neatly in the strands of the 16, that would work and be cost effective.
Does it need fusing down or has it been done at the other end (upstream) of the 16mm?

Being fused down at the other end.

 

[littlespark]

IP enclosure with suitable devices- Like a caravan hookup unit- fixed to the nearest wall or shed.

 

[ChrisElectrical88]

Question.
Why did the builder put in 16mm in the first place?
Tell him to dig it up and put in the right size.

or

Tie the cores to a jcb and gently pull it. It will either stretch the 16mm's down to a usable csa, or pull the cores out from within the armour. If that works, then tie a flex onto the other end and pull it in as the 16 comes out.
The "optimistic" badge is below, just about...……………....…. here!
Looks like a rainbow

I gave you an optimistic, for been optimistic about getting an optimistic

 

[Flanders]

How about using a submarine joint like this , Resin Underground SWA Armoured Cable Joint Kit 1.5mm-16mm 2,3,4 core cable | eBay - https://www.ebay.co.uk/itm/Resin-Underground-SWA-Armoured-Cable-Joint-Kit-1-5mm-16mm-2-3-4-core-cable-/263575621918?redirect=mobile

 

[Yozza19]

63a rotary isolator or a 63 interlocked socket with the pond flex on a 63a plug
Then it’s also got a local isolation point for maintaince

 

[rolyberkin]

I've been looking in my recycling bag and have found some old CU brass connection blocks, I am thinking judicious use of an angle grinder and some heat shrink all housed in a wiska box and Bob's your uncle.......!

 

[Devonchris]

If the size of the conductor is going to be reduced from 16mm to 1.5mm then, leaving aside the IPxx rating, and providing its all tidy and insulated, could someone please explain why the suggestion of using a single strand into a wago would be frowned upon. To me it seems a practical way to reduce the conductor. What am i missing?

 

[pirate]

Jubilee clips...

 

[Midwest]

So do you condone that form of butchery then? Should have had the right sized cable installed in the first place, and not left it to a builder,who probably thought "got some 10mm in the shed, I know I'll use that"

Well we are where we are with things here. Can't see its going to cause probs for this particular example? Have you never gone to bed at night, and not brushed your teeth.

 

[TJ Anderson]

At least volt drop won't be an issue!! Lol

 

[Lucien Nunes]

providing its all tidy and insulated, could someone please explain why the suggestion of using a single strand into a wago would be frowned upon.

Electrically, of course, it would be fine. It's the ethics that are screwed up here. Leaving strands out of a termination violates a fundamental rule that is deeply imprinted in any (good) electrician's brain. Plus the Wago instructions would probably be disobeyed in two or three different ways.

A technically correct solution would be as suggested by Shaun1, to terminate the two cables into appropriate-sized DIN terminals and link them with commoning bars. Or to crimp on some suitable ring terminals (e.g. 6mm hole) and connect them via DIN-rail mounted insulated stud terminals. I have used that method before, for widely disparate cables sizes. There are all sorts of halfway house options, like lap crimps. Soldering, if done with skill, could make a nice job of it.

But I might still go for the 1-strand-in-a-Wago. In an outdoor terminal box, the less exposed metal and fewer things to corrode or create leakage, the better. From a purely engineering standpoint, provided the heatshrink job is well executed, it might be the most suitable technique. I leave for the reader the agonising consideration of inter-strand resistance after a few years of moisture ingress, vs. the equalisation of current between strands along the length of the cable.

 

[Deleted member 26818]

Conduit through box.
Gland the SWA to one side, plastic stuffing gland and flex the other side.
Choc blocks to make the terminations, fill with magic gel or resin.

 

[Devonchris]

Leaving strands out of a termination violates a fundamental rule that is deeply imprinted in any (good) electrician's brain

Thank you for the detailed reply. My quote above confirms my thoughts.

 

[DPG]

Anyone who just uses a couple of strands in a termination and cuts the rest off should be put on some sort of register.

 

[Deleted member 26818]

Anyone who just uses a couple of strands in a termination and cuts the rest off should be put on some sort of register.

Although it sounds terrible, if you stop and think about it.

 

[DPG]

Although it sounds terrible, if you stop and think about it.

It does indeed.

 

[w0z]

If the size of the conductor is going to be reduced from 16mm to 1.5mm then, leaving aside the IPxx rating, and providing its all tidy and insulated, could someone please explain why the suggestion of using a single strand into a wago would be frowned upon. To me it seems a practical way to reduce the conductor. What am i missing?

...because it would only work properly if the same few strands were connected at the other end...?

 

[Pete999]

...because it would only work properly if the same few strands were connected at the other end...?

No they will all be joined by close encounters, ohhherrrr

 

[pirate]

Clearly, as w0z said, you have to be sure the same few strands are connected at each end...
but somehow I don't think my new RJ45 crimper is going to be man enough for the job...

(nor the cat6 cable, to be fair)

 

[mydigitalhome]

I would agree with Midwest comment

 

[freddo]

Isn't an approved method to leave a strand long to terminate, then solder all the strands together, finally cover with heatshrink?

 

[DPG]

Isn't an approved method to leave a strand long to terminate, then solder all the strands together, finally cover with heatshrink?

Still sounds a bit bodgy to me that though.

 

[freddo]

Like this 16mm:

 

[Pete999]

Isn't an approved method to leave a strand long to terminate, then solder all the strands together, finally cover with heatshrink?

Don't think so

 

[freddo]

 

[Pete999]

View attachment 48418

Well I never did! goes against the grain though.