SY Cable? Thoughts?

[Deuce]

This has come up before.. What is the right thing to do? On some machines you can't rely upon RCD protection so you kind of need a cable with mechanical protection built in, and earth sheathed in case it is damaged/crushed.

Always feels to me like an unfair choice, to either downgrade real-world safety in order meet the regs, or follow common sense and risk criticism for it.

 

[Darkwood]

SY and machinery, depends on the environmental influences, SY usually requires other IP and mechanical protections around machinery as it is not suitable to the oils, coolants etc commonly used, also it shouldn't really be bought as a mechanically enhanced protected cable, this is a screening and originally design for screening purposes, it should have additional mechanical protection if used in areas where it may be subject to damage etc.

 

[westward10]

This biggest problem if you decide to use the braid which you shouldn't, as part of a means for ADS is assessing the braids capability of carrying fault current.

 

[Deuce]

SY and machinery, depends on the environmental influences, SY usually requires other IP and mechanical protections around machinery as it is not suitable to the oils, coolants etc commonly used, also it shouldn't really be bought as a mechanically enhanced protected cable, this is a screening and originally design for screening purposes, it should have additional mechanical protection if used in areas where it may be subject to damage etc.

This biggest problem if you decide to use the braid which you shouldn't, as part of a means for ADS is assessing the braids capability of carrying fault current.

Fair points.

The thing is, the braid is a useful last defence if the cable is damaged (unnoticed) and then someone touches it. In general, it's also pretty tough stuff. Designed for screening, but designed to be extra tough too.

Even 'fixed' machines get moved away from walls for servicing etc. Damage can occur at anytime and for me, SY feels like a good choice. I accept the braid can't be relied on solely, but one day it might be in the right place to save a nasty incident. Just feels right to earth the surface of exposed cable if it's possible to do so.

 

[Darkwood]

A few points to note:-

SY cable does not comply to British Standards in using it you will have:-
A- understand why it does not comply.
B- document its use and why you believe it is suitable for your installation.

The use of this cable in the industry brought it big concerns and was clearly been used for purposes it was never designed for or was suitable for.
If you have it on or around machinery where it may come into contact with the normal oils, greases, coolants etc used then it should not be used.
If it is subject to possible damage then it should not be chosen in the mindset that it is a armoured flex, it is not it is a screened flex which can afford some kinds of damage a standard flex couldn't but also it is prone to damage where other flexes would be resistant IE UV damage, outer sheath is softer than standard pvc environmental covering and it has low resistance to chemicals and oils.

I conclude this cable should not even be in our industry, it is mi-sold, misused and has forced the regulatory bodies to step it and express its use does not conform to our recognised standards.

I have a pet hate of this cable because of the amount of times I have seen the result of its poor application, I have in 2 decades found several times that damaged cable has made the sheath live and in some cases given uses shocks simply because of misuse and the wrong applications of its use.

I would say if you have routine machine movement for maintenance and cleaning then wire it with a suitable HO7RN-F a cable designed for the purpose of most industrial environments and put it on a plug and socket arrangement so it can be disconnected, I have done this for many decades and never had issues, if you find you are then the operators/employees need educating and taught how to clean and service the machines safely.

 

[Leroy Merlin]

A few points to note:-

SY cable does not comply to British Standards in using it you will have:-
A- understand why it does not comply.
B- document its use and why you believe it is suitable for your installation.

The use of this cable in the industry brought it big concerns and was clearly been used for purposes it was never designed for or was suitable for.
If you have it on or around machinery where it may come into contact with the normal oils, greases, coolants etc used then it should not be used.
If it is subject to possible damage then it should not be chosen in the mindset that it is a armoured flex, it is not it is a screened flex which can afford some kinds of damage a standard flex couldn't but also it is prone to damage where other flexes would be resistant IE UV damage, outer sheath is softer than standard pvc environmental covering and it has low resistance to chemicals and oils.

I conclude this cable should not even be in our industry, it is mi-sold, misused and has forced the regulatory bodies to step it and express its use does not conform to our recognised standards.

I have a pet hate of this cable because of the amount of times I have seen the result of its poor application, I have in 2 decades found several times that damaged cable has made the sheath live and in some cases given uses shocks simply because of misuse and the wrong applications of its use.

I would say if you have routine machine movement for maintenance and cleaning then wire it with a suitable HO7RN-F a cable designed for the purpose of most industrial environments and put it on a plug and socket arrangement so it can be disconnected, I have done this for many decades and never had issues, if you find you are then the operators/employees need educating and taught how to clean and service the machines safely.

Thanks for the replies, I'll pass this upstairs... Just spoke with RS and asked if they could confirm if it was OK to use in the UK and if they have any BS7671 compliant SY, as you would expect, they said not...

 

[Darkwood]

Here is an informative read up ...

Should SY, YY and CY cables be used in electrical installations? - https://www.voltimum.co.uk/articles/should-sy-yy-and-cy-cables-be-used

PS - I will admit I use it myself but only when I know that it is suitable and not subject to any environmental concerns, I use CY for motor VSD control and sometimes the motor supply as it affords a suitable screening.

 

[Spoon]

Thanks for the replies, I'll pass this upstairs... Just spoke with RS and asked if they could confirm if it was OK to use in the UK and if they have any BS7671 compliant SY, as you would expect, they said not...

I remember when I noticed the manufacturers has put the 'not suitable for fixed installations' note on their SY cables, RS cables had not added this note for their SY cables. I contacted them, showing them the other cable manufacturers notes and asked if their cable was suitable for fixed installations. They said they they would changed the description of theirs to suit the other manufacturers.

 

[suffolkspark]

 

[Spoon]

View attachment 45609

There you go mate. Nice screen shot of it.

 

[suffolkspark]

Cheers i took mine on my phone last night as was having this very chat with another spark who was wiring up a joule cylinder and heat pumps and the manufacturers instructions sugested using SY!!!

 

[Deuce]

Guess that's this debate ended then.

Got to say though, I see the h07 get damaged all the time too. Mostly deep nicks in the outer sheath. In fairness, in my industry 20m lengths of it are dragged around and left laid on the floor/gravel/grass whatever - and then walked over for a couple of weeks before getting dragged back into a flight case

 

[Spoon]

Cheers i took mine on my phone last night as was having this very chat with another spark who was wiring up a joule cylinder and heat pumps and the manufacturers instructions sugested using SY!!!

I can cheat. We got the 18th and OSG for work. I took them to bits and PDF/OCR them. Makes it so you search them easily.

 

[Midwest]

Here is an informative read up ...

Should SY, YY and CY cables be used in electrical installations? - https://www.voltimum.co.uk/articles/should-sy-yy-and-cy-cables-be-used

PS - I will admit I use it myself but only when I know that it is suitable and not subject to any environmental concerns, I use CY for motor VSD control and sometimes the motor supply as it affords a suitable screening.

Didn’t Massive 1 already post that link?

 

[Darkwood]

Guess that's this debate ended then.

Got to say though, I see the h07 get damaged all the time too. Mostly deep nicks in the outer sheath. In fairness, in my industry 20m lengths of it are dragged around and left laid on the floor/gravel/grass whatever - and then walked over for a couple of weeks before getting dragged back into a flight case

I suggest it is not that the cables are a poor choice but the fact you are running them along the ground in a harsh environment, you need to look into other suitable means like cable protection channelling like they use on road works etc, we have this set up in the factories I work in, also voltages used should be considered IE 110v gear.

I understand that sometimes they cables will be subject to some wear and tear but if this is the case then more routine checks and replacement may be the only real answer but I struggle to see that there isn't any other solutions, we have in the past dug the floors up and put cable raceways in to allow power points at better suited positions minimising extension runs.