SWR 12

South Wales Switchgear Retrofit

The SWR12 is an OEM designed vacuum retrofit circuit breaker for both the South Wales Switchgear ‘C & D’ range, including the C4X and D4X, Oil Circuit Breaker and the HawkGas12 Gas Circuit Breaker, to IEC 62271-100.

Employing magnetic actuator technology with vacuum interrupters, the SWR12 is designed for 10,000 operations and a life expectancy of 30 years. It is designed for retrofitting into existing switchboards without the need for panel modification.

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Click here for an example of how the SWR12 has benefited Western Power Distribution.


  • Superior, proven 'Fit & Forget' technology with minimal maintenance;
  • Remove the need for high capacity auxiliary supplies.
  • No civil works required and existing HV cabling remains undisturbed.
  • Improvement of Health & Safety by removal of Oil or SF6 gas.
  • Considerable life extension of the existing switchgear.
  • Lower owner costs through virtually no maintenance requirements and increased switchboard life expectancy.
  • Uses existing design of primary and automatic secondary contacts.
  • Improved panel interlocking to latest ENA requirements.
  • In addition to the retrofit of the circuit breaker Hawker Siddeley Switchgear can offer a more complete system solution to enhance the control and automation of the distribution network.


Normal Rated Currents

A 400/630, 800, 1250

Rated Voltage

kV 12

Lightning Impulse Withstand Voltage

kV 75

Short Duration Power Frequency Withstand Voltage

kVP 28

Rated Frequency

kV 50

Rated Short-Time Withstand Current

Hz 25

Rated Peak Withstand Current

kA 62.5

Rated Duration of Short Circuit

kA Peak 3

Making Current (peak)

Seconds 62.5

Symmetrical Breaking Current

kA 25

Rated Short-Time Current (3 Sec)

kA 25

Rated Auxiliary Voltages

kA 30, 48/50, 110/125

Minimum Opening Time / Closing Time

V dc 33ms/76ms

Normal Operations

ms 10,000


Kg 211



The SWR 12 has a wide range of applications:

  • Primary distribution
  • Secondary Substation
  • Utilities
  • Transport
  • Building Services
  • Light Industrial
  • Commercial
  • Education
  • Hospitals
  • MOD

get in touch

Contact HSS

+44 (0)1495 223001

+44 (0)1495 223001

+ 61 7 3888 2333

what we've done

case studies

ENWL Case study Wilmslow retrofit ENWL approved

SSEN - Horizon Framework