What is meant by 4-core CY cable?

[LawcockLD]

For future reference, YY is pretty much the same as standard flex, CY has mechanical protection in the form of tinned copper braid and SY has mechanical protection in the form of steel braid. CY is rated low to medium protection and SY rated as medium to high protection. This is what I've always been led to believe, however I could have been misled.

[irving2008]

For future reference, YY is pretty much the same as standard flex, CY has mechanical protection in the form of tinned copper braid and SY has mechanical protection in the form of steel braid. CY is rated low to medium protection and SY rated as medium to high protection. This is what I've always been led to believe, however I could have been misled.

You should only use CY for CNC equipment, especially the connections to moving parts, as the SY isn't flexible enough. Here's the official blurb, taken from http://www.bs6500.co.uk/

"Control Cables
YY Control Cable, SY Control Cable and CY Control Cable are flexible instrumentations cables – with a voltage rating of 300V/500V – designed for use as an interconnecting cable in signal and control equipment – for measuring, control or regulation.

YY Control Cable to BS6500
YY Control Cable is a multi-core cable with class 5 stranded copper conductors, PVC insulation and a grey PVC sheath. YY Cable is also referred to as Unscreened, Flexible or Unshielded Control Cable and YY Control Flex. Projects in public buildings, such as offices, schools and hospitals will specify a LS0H version of YY Cable. Similar in construction to the YY PVC Control Flexible Cable, the LS0H YY Flex uses XLPE insulation and a grey LS0H sheath in place of PVC layers.


SY Control Cable to BS6500
SY Flex is a built in much the same way as YY Control Cable – with class 5 flexible annealed plain copper conductors, PVC insulation and a transparent PVC sheath. SY Control Flexible Cable has the added benefit of a galvanised steel wire braid with PVC bedding for mechanical protection so it can cope with situations of medium to high stress. SY Cable is also known as Flexible or Braided Control Cable, and SY Control Flex.


CY Control Cable to BS6500
CY Cable is a flexible multi-core cable with class 5 flexible plain copper conductors, PVC insulation, a plastic core wrap, a tinned copper wire braid and a grey PVC sheath. The construction of a LS0H CY Control Cable differs slightly – XLPE (Cross-Linked Polyethylene) insulation and a LS0H sheath are used in place of the PVC layers. CY Cable is also known as Instrumentation Cable, CY Flex, CY Control Flex, Robotic Cable, Copper Screened Control Cable, Shield Control Cable, Motor Cable, Multi-core Cable and Screened Cable."

[MikeyC38]

Hi irving2008

Thanks for the post on this. I have used 2.5mm2 4-core SY cable for connecting up my 2.2kw spindle to the VFD. Got an offcut from Premier Cables really cheaply so I will use them as my first port of call. They sell to large users and they said it's good for them to sell off the offcuts so it reduces the stock taking efforts!

- Mike