ENATS 09-6 is the UK electricity supply industry specification for armoured multipair cables used as pilot, control and communication links around substations and power stations. Solid copper conductors are twisted into pairs, insulated in PVC and protected by galvanised steel wire armour under a black PVC sheath. The armour makes it suitable for direct burial and for runs through plant areas where mechanical damage is a real risk.
Key applications
- Pilot wires for feeder protection schemes
- Substation control and indication circuits
- Alarm and annunciator wiring between switchgear and control rooms
- Power station instrumentation and interlock links
- Trench and duct runs between substation buildings
- Telemetry and SCADA field wiring on utility sites
Features and benefits
- Galvanised steel wire armour withstands burial and mechanical impact
- Twisted pairs reduce crosstalk between circuits in the same cable
- Pair counts up to several tens keep multiple circuits in one cable run
- Specified to a recognised electricity industry standard, simplifying utility approval
- Flame retardant to BS EN 60332-1-2
Specification notes and limitations
This is a low voltage control and communication cable rated at 150 V d.c. or 110 V a.c., not a power cable: it must never be pressed into service on a 230 V or 400 V supply circuit. Pilot circuits can nonetheless rise to dangerous potentials under earth fault conditions on a substation site, so the cable must be terminated and earthed in accordance with the protection scheme design and isolating transformers fitted where the scheme calls for them. PVC should not be installed below 0°C, and buried runs need the usual sand bed, marker tape and depth of cover. Respect the armoured-cable bending radius at glands and never use the armour alone as the earth path for a scheme that specifies a separate earth continuity conductor.
