circuits wired in flex?

[Hawk81]

In your case then, ...We'll call it ''hard wiring''!! ...OK

Personally, i don't really care what or where you, or anyone else uses it!! Just don't try and come here and convince us, that this practice is perfectly normal cause it isn't and never has been. What it is, ....is easy installation!!

Brilliant and informative answer.

 

[Engineer54]

Someone please tell me the major difference in having flex and twin and earth clipped above a ceiling? A serious and proper answer not rubbish like flex was not intended for this use or it's bad practice

What can't you understand then, about not being manufactured for the intention for use as hard wiring?? Is that not a good enough reason for you? If you want to use a flexible cable above and around ceilings as you circuit medium, use a flexible cable that IS intended for use as a hard wiring cable. It's simple logic really!!!

 

[Mr.Ian]

there is no reg against using flex as long as its the correct size and as for strands coming of when stripping . .well practice a bit more and strip it correctly easy hmmn

Just to set the record straight, after 30 odd years of stripping 'flex' for terminating I do not need to practice, and as far as i'm aware any multi strand flex when disconnecting for testing and re connecting will if care isn't taken get damaged.

 

[Hawk81]

What can't you understand then, about not being manufactured for the intention for use as hard wiring?? Is that not a good enough reason for you? If you want to use a flexible cable above and around ceilings as you circuit medium, use a flexible cable that IS intended for use as a hard wiring cable. It's simple logic really!!!

Where do you get your information on what flex is manufactured intention is?

 

[Big n Daft]

Leaving aside the can you or cant you issue..........................
How much is flex compared with twin n skin????

 

[Engineer54]

Where do you get your information on what flex is manufactured intention is?

H05 type flexible cables are generaly intended to supply appliances and equiment. I'm not too conversant with European cable designation numbers these days, more conversant with the Yank/Asian systems.... But i think the attached is a pretty good example of what i'm talking about, if these are the cable designation types that are being used for hard wiring....

Application: 318-Y Cable H05VV-F to BS6500For use in household appliances such as washing machines, spin dryers and refrigerators. Generally unsuitable for outdoor use or industrial applications.Standards:
0.5 - 2.5mm² to BS6500,
4.0mm² to BS7919
6.0mm² generally to BS7919
VDE28
CENELEC HD21.5


Application: 309-Y Flexible Cable H05V2V2-F to BS6500Supply leads for use as 318-Y but particularly for use in high temperature zones, for internal wiring or supply cords to electrical apparatus. Not suitable for outdoor use.Standards:BS6500, BS7919 above 4.0mm²Conductor:Class 5 flexible plain copper to BS EN 60228:2005 (previously BS6360)InsulationVC (Polyvinyl Chloride) Type TI 3 to BS7655SheathVC (Polyvinyl Chloride) Type TM 3 to BS7655Colour:WhiteVoltage Rating:300/500VTemperature Rating:0 to +90°CMinimum Bending Radius:6 x overall diameterCore Identification:
2 Cores: Blue, Brown
3 Cores: Green/Yellow, Brown, Blue
4 Cores: Green/Yellow, Brown, Black, Grey
5 Cores: Green/Yellow, Brown, Black, Grey, Blue
RoHS Compliant



Application: 318-TQ Cable H05BN4-FFlexible cords suitable for use in domestic premises, kitchens and offices. Also suitable for use in hot situations such as immersion heaters. Good resistance to oil and grease.Standards:BS6500, VDE 0282Conductor:Class 5 flexible plain copper conductorsInsulation:EPR (Ethylene Propylene Rubber) CompoundSheath:HOFR Compound (Heat & Oil Resistant, Flame Retardent)Sheath Colour:WhiteVoltage Rating:300/500VTemperature Rating:-35°C to +85°CMinimum Bending Radius:6 x overall diameterConductor Identification:
3 Cores: Brown, Blue, Green/YellowRoHS Compliant

 

[sbrown2]

As somebody who has had only a year and a half in the domestic sector, and having a mining background, I like the idea of using flex instead of single wired armoured!!!!!!

 

[Guest112]

ive had this conversation with engineers in the past and they reckon the only reason we dont always use flex is because of cost, apart from that there isnt anything wrong with it apparently.

and as for numptys cutting strands out when striping ends is this any different to them cutting into a solid core slightly when stripping solid strand cables? #

I worked in a steelworks alongside a big italian electrical contracting firm who were also pulling in and connecting large cables but every cable they pulled in were large flexible cables much easier to work with on a larger scale, have better current carrying capabilities and also better for terminating.

not that I use flex to hardwire from dbs but ive seen it done especially in office environments, but i have used flex between lighting in office situations at the clients request,

and as for "appliance flex" i dont know what e54 means there but when i order a drum of flex from the wholesalers it just says flexible cable on it and i just make sure its the right size for its purpose and is a reputable brand.

flex is great in situations where movement is expected like i said in office ceilings but i personally hope it doesnt become a form of hard wiring because i can strip a t+e quicker than i can a flex

 

[Marvo]

H05 type flexible cables are generaly intended to supply appliances and equiment. I'm not too conversant with European cable designation numbers these, more conversant with the Yank/Asian systems.... But i think the attached is a pretty good example of what i'm talking about, if these are the cable designation types that are being used for hard wiring....

Application: 318-Y Cable H05VV-F to BS6500For use in household appliances such as washing machines, spin dryers and refrigerators. Generally unsuitable for outdoor use or industrial applications.Standards:
0.5 - 2.5mm² to BS6500,
4.0mm² to BS7919
6.0mm² generally to BS7919
VDE28
CENELEC HD21.5


Application: 309-Y Flexible Cable H05V2V2-F to BS6500Supply leads for use as 318-Y but particularly for use in high temperature zones, for internal wiring or supply cords to electrical apparatus. Not suitable for outdoor use.Standards:BS6500, BS7919 above 4.0mm²Conductor:Class 5 flexible plain copper to BS EN 60228:2005 (previously BS6360)InsulationVC (Polyvinyl Chloride) Type TI 3 to BS7655SheathVC (Polyvinyl Chloride) Type TM 3 to BS7655Colour:WhiteVoltage Rating:300/500VTemperature Rating:0 to +90°CMinimum Bending Radius:6 x overall diameterCore Identification:
2 Cores: Blue, Brown
3 Cores: Green/Yellow, Brown, Blue
4 Cores: Green/Yellow, Brown, Black, Grey
5 Cores: Green/Yellow, Brown, Black, Grey, Blue
RoHS Compliant



Application: 318-TQ Cable H05BN4-FFlexible cords suitable for use in domestic premises, kitchens and offices. Also suitable for use in hot situations such as immersion heaters. Good resistance to oil and grease.Standards:BS6500, VDE 0282Conductor:Class 5 flexible plain copper conductorsInsulation:EPR (Ethylene Propylene Rubber) CompoundSheath:HOFR Compound (Heat & Oil Resistant, Flame Retardent)Sheath Colour:WhiteVoltage Rating:300/500VTemperature Rating:-35°C to +85°CMinimum Bending Radius:6 x overall diameterConductor Identification:
3 Cores: Brown, Blue, Green/YellowRoHS Compliant

'Flex' is an awful term. I also sometimes refer to HO5 AND HO7 neoprene trailing cabling as flex but I think what they're referring to as flex in this thread here is what we call 'PVC cabtyre'.

 

[gap30]

wow! this thread opened a can of worms.

I frown on flex in db's to hard wire circuits, i know there is no reg against it but it smacks of diy to me, it seems that most sparks are split on this one.

anyway i wont be listing it as a remedial anymore, fack it i am starting to lower my standards these days....

 

[Ric2013]

Plumber here. I know this is an old thread, but still interesting.

From my perspective, heating controls are probably largely wired with flexible cable because we often need 4 cores, or 4 cores and earth.

For example, to reach distant motorised zone valves, or to carry L(p) L(ch) L(dhw) N(p) and E between a wiring centre and a programmer. I personally dislike running two parallel T+Es between 2 enclosures, not so much because it's a waste of materials and time, but because it seems somehow wrong and gives me an extra earth to terminate in busy enclosures.

3C+E is available as a solid cable, but I'm not sure that 4C+E is, or not that I've seen. So I'm forced into a dilemma: double up on solid cables, or use flexible cable. Any suggestions for improvement are welcome, and if a good spark in Colchester is on here that actually understands heating controls, then I may have some work for them some way down the line, if they want it.

 

[littlespark]

Old, @Ric2013 ?
It’s practically Jurassic!

I only recognise one name so far.


I think it was mentioned that although compliment, flex is more expensive, and therefor only used in short lengths to appliances or equipment.

In the instance of heating controls…. Most come with flex already attached and it’s a job of connecting all the ends together in the wiring centre…. (Or as we call them- “joint boxes”)

If there’s a longer length required, say to a room stat, then it would normally be 6243y 3core and earth.

 

[Ric2013]

Old, @Ric2013 ?
It’s practically Jurassic!

I only recognise one name so far.


I think it was mentioned that although compliment, flex is more expensive, and therefor only used in short lengths to appliances or equipment.

In the instance of heating controls…. Most come with flex already attached and it’s a job of connecting all the ends together in the wiring centre…. (Or as we call them- “joint boxes”)

If there’s a longer length required, say to a room stat, then it would normally be 6243y 3core and earth.

My personal, unqualified person's feeling, is that I agree that cost is probably the main (although not the only) driver behind the UK's continued use of solid core flat cable.

How would I connect to a 2 port valve with 6243 though? I need:

N(p)
L(call from stat)
L(p)
L(switched from "L(p)" by microswitch inside the 2-port valve)
Earth (not always)

which is 4-core and earth. We're back to 2 parallel lengths of 6242 cable (which is normally how I would do it - one cable is a switch wire and the other carries the live and neutral to power the 6W valve motor). In practice, you can get a bit of flexible cable and a Wago box and extend the tail, and I'm thinking this is a better solution in a way, the beauty of this being that future tradesmen will know that everything in that cable core goes to the same destination (not sure if this also reduces the EMF created compared with two parallel 6242s?).

Ideally, everything would be close to the joint box and all as you say above. In practice, houses evolve and it's easier to rewire than repipe. This means cylinder stats can often be remote from the programmer and the hypothetical joint box ends up being split between several enclosures. For example, if the cylinder stat and zone valve for the hot water are one end of a house, it makes sense to have a box near the two to switch the switched live to the valve motor rather than run an extra length of 6242 to act as a pair of switch wires all the way back from the joint box if that is at the other end of the house. But you still need 4 cores and earth between the 'main' and 'secondary' joint boxes.

My understanding was that if flexible cable is used it should be visible throughout its length, but not sure who made that rule and how precisely they defined 'visible', nor what happens when the only place the already-attached-flex HAS TO start under the floor because that is where the 2-port valve is or realistically has to go. Quite happy to run my concealed control cables in 6242 and 6243 (in fact, I usually do), but would be nice to know exactly why I'm doing it and when I have to do it, and can quite understand why many don't. (Better still I'd get a local sparky if I knew one that both understood heating controls and was interested in doing the work.)

Reason I bring this all up is #24. I find the plumbers vs electricians thing an example of what is wrong with the construction industry. I've heard your points of view and I thought you might appreciate a bit of insight from the other side. And interested... would you really run two number 2-core T+E rather than a 5 core flexible cable?

 

[nicebutdim]

Solid multicore cables are available and widely used, although not so much in domestic installations.

 

[Lucien Nunes]

It's an interesting discussion and your points are well reasoned. Much of the historical comment on the thread was rather polarised. It was from a time when there were two distinct and cliquey schools of thought on this forum about many topics which tended to override logical, fact-based discussion.

3C+E is available as a solid cable, but I'm not sure that 4C+E is, or not that I've seen

Not as flat T+E, but fire performance cable ranges usually include a 4C+E option as does NYY-J. And indeed many European styles of cable.

would you really run two number 2-core T+E rather than a 5 core flexible cable?

No, but I don't work in the domestic sector so I hardly ever use 6242. Conversely, 4C+E FP is a stock item for me. If I didn't have that, I would be happy with 3185Y. I also tend to work abroad at times so I even keep continental wiring cables on the shelf. And in an ideal world I would be happiest wiring it in 4L1 MICC.

(not sure if this also reduces the EMF created compared with two parallel 6242s?).

Not many people seem to have taken this into account until it was highlighted in the regs, although the phenomenon has always been there. TBH if the 2x 2C+E are adjacent, there's not much in it and I wouldn't worry about it. And in some cases each cable is a complete circuit (e.g. your motorised valve motor cable / switch cable example.)