H07RN or SY extension cable choice?

[Fredxx]

This is for a 10m 3-phase 5 pin extension cable.

There seems a choice of H07RN or SY cable. I am aware that H07RN cable
is certified to a couple of standards whereas the SY isn't.

Nevertheless SY does seem very popular and provides some mechanical
protection. The circuit is also protected by an RCD which makes the SY
cable with its light-weight steel braid. The SY is a slightly smaller
diameter.

Are there any views on which is best?

[Owain Lastname]

SY is acceptable provided you meet the requirements for glanding the braiding:

"Standard industrial plugs and sockets are, likewise, not generally designed to accommodate a steel braid. If it is felt that a steel braided flexible cable should be used because of the greater physical protection offered (such as SY type), then an appropriate plug / socket system must be used, with the appropriate gland and termination for the braid. These plugs are available from specialist suppliers. The braid needs to be bonded to earth."
https://www.voltimum.co.uk/articles/q-day-extensions-using-sy-braided-1

It also needs to be suitable for the environment in which it is used:

"should also not be applied to a floor in a working environment, unless covered and protected, the cable should be run around the parimeters and away from potential hazards.
Not governed by any specific standards and does not fall under BS7671 Standards.
SY cable can often be seen outdoors at events. This is not recommended in BS7909 2011, despite its widespread use.
BS7909 2011 recommends the use of HO7 RN-F cable for outside use.
Ref BS7909 2011 Code of Practice for Temporary Electrical Systems for entertainment and related purposes."
https://www.essentialsupplies.co.uk/6mm-sy-flexible-3-core-control-cable.html

SY clear sheathing also has very poor UV resistance. It's specifically a control cable, not a power cable.

Owain

[Fredxx]

Thanks for that. These are ready made extension cables so hopefully the
braid would be suitably earthed, or they become a hazard rather than
protection.

The use is internal so UV shouldn't be so much of an issue.

I'm left wondering if I should simply go for the H07RN extensions.