Second Opinion on Modification to Existing Circuit

[lozarus]

What are the concerns with using the existing SY cable in this case? (I don't know much about the stuff, have only come across it a couple of times)

The majority of it complies with European DIN standards, not BS. Thats not to say it can't be used, just that we have to satisfy ourselves that it meets or exceeds British standards.

Also in a lot of cases the manufacturer states its a control cable, not a distribution cable - so theres the manufacturers instructions side of things.

In my specific instance the braid has been taped off and not connected to the CPC and not d9ne with a proprietary SY gland - so hasnt been installed correctly

That said ive never actually seen it installed correctly...

 

[Dustydazzler]

Isn't SY cable a signal cable or something ? only to used to connect up certain things like AC units, and not to used as a distribuition cable

 

[nicebutdim]

In my specific instance the braid has been taped off and not connected to the CPC and not d9ne with a proprietary SY gland - so hasnt been installed correctly

That said ive never actually seen it installed correctly...

Even in industrial applications the braid never seems to be glanded correctly, with it cut off and both ends of cables shoved into stuffing glands.

I hope this is highlighted in periodic inspections - especially when only recently installed.

 

[lozarus]

Even in industrial applications the braid never seems to be glanded correctly, with it cut off and both ends of cables shoved into stuffing glands.

I hope this is highlighted in periodic inspections - especially when only recently installed.

Yeah - its sods law that ive ended up coming back to this location - I posted a thread a few months back whereby I disagreed with the contractor installing this and was trying to code it. Despite everything we've said here it was quite hard to do...

 

[nicebutdim]

Yeah - its sods law that ive ended up coming back to this location - I posted a thread a few months back whereby I disagreed with the contractor installing this and was trying to code it. Despite everything we've said here it was quite hard to do...

I half remember that discussion, but not the outcome. Surely at least one end needs to be earthed? I've never used SY in a professional capacity and have been briefly familiarised with its glanding as it forms part of the AM2.

 

[Flanders]

Isn't SY cable a signal cable or something ? only to used to connect up certain things like AC units, and not to used as a distribuition cable

The problem.. with sy cable is that its not recognised by bs7671 although there are tables on line with current carrying capacity detail. We only used it for long runs on 24 volt access control and BMS . But you see it all the time used on Air con systems. that not to say its correct and when used outdoors water get into the cable on corrodes the braiding

 

[lozarus]

I find it such an odd choice of cable when there's so many others - much more suitable - available.

In another area we have BMS guys working on the plant rooms at the moment. They seem to love it. Which I can sort of get because it is a "control cable". However they've used some on a catenary to a remote plant room - and it isn't UV rated. Their commercial spark also used it to make up the 32a flylead om CEEform to the site cabin. I just don't get it? Last time I did a flylead I used H07 due to its tough sheath, pliability and UV resisting properties.

The circuits in this kitchen could have just as easily been done with T&E.

I fitted the radial for the water heater today. The walls were a bit wibbly wobbly so I went for FP200 rather than trunking or conduit - I wouldn't have even considered SY so no idea why this guy did.

Glad I didn't adapt his 32a 6mm radial. Once I was up my steps I could see that he'd forced it under the metal roller shutter housing and wrapped a load of tape around it - in what I assume wasa bit an attempt to stop it feeling the effects of the roller shutter vibrating.

And just to add a bit of context this is in a school. Most regular schools don't have specialists employed as staff - so I assume this sort of bodgery is very much commonplace as it will all be getting approved by the "unskilled" Teachers / Business Managers at the lowest cost.

I got employed as the Estate Manager with electrical bias and inherited this rubbish.

For what its worth the more recent Council / Local Authority work is just as terrible

The VIR singles and MICC installed when it was built in the 60's however is all a work of art - except where it's been tampered with by the aforementioned ropey contractoes

 

[nicebutdim]

And just to add a bit of context this is in a school. Most regular schools don't have specialists employed as staff - so I assume this sort of bodgery is very much commonplace as it will all be getting approved by the "unskilled" Teachers / Business Managers at the lowest cost.

I got employed as the Estate Manager with electrical bias and inherited this rubbish.

For what its worth the more recent Council / Local Authority work is just as terrible

In the college I attend all electrical work is carried out by a maintenance company.

Their work is nothing to write home about and I'm won't begin to describe how long they can milk the simplest of tasks.

 

[lozarus]

In the college I attend all electrical work is carried out by a maintenance company.

Their work is nothing to write home about and I'm won't begin to describe how long they can milk the simplest of tasks.

Yup. Up until i started and built a team of general maintenance bods (think retired plumbers, a couple of young lads wanting to learn a trade who I've put on courses etc) rather than just "caretakers", they were using the council helpline for everything - broken sockets to a tap washer. The council obviously sub it out to the general maintenance companies. When I started I walked around with one of the maintenance subbies who was trying to diagnose a heating issue. I watched him declare that the 'cable here is the switch live so will be dead' - whilst I was thinking 'no, that has to be the perm'. And then watched him get a belt.....

 

[James]

Sy cable has its uses, it is of course screened so suitable for connecting motors to inverter drives where emc may be a problem.

i did once have a situation where I installed a machine using tough rubber cable.
the MD called me back and told me it was not acceptable and had to be done in ”armoured cable” for safety.
didn‘t argue, came back and changed it for armoured as that is what the customer wanted.
next day I got called back and had a roasting because he wanted “flexible armoured cable”
I told him that I have never heard of such a product and he showed me something wired in sy.
a bit of client education about the different cable types, involving a mallet and a knife, showed him that the sy was weaker than the rubber and nothing beats armoured cable for resistance to destruction.

put it back to tough rubber flex and got paid for doing the job 3 times!!