Ageing Switchgear can be given a life extension of up to 30 years by simple replacement of the circuit breaker.

P&B has been designing, manufacturing and installing retrofit switchgear or circuit breakers for more than 25 years and is now considered to be a global market leader in this specialist field.

Our experience includes medium voltage vacuum breaker design and type testing to replace air and oil breakers manufactured by a broad range of UK suppliers going back to the 1960s and sometimes earlier.

Benefits of Retrofit Switchgear

Benefits over replacing complete switchboards

Retrofits vs. Replacements

“Retrofitting” has become a generic term and can mean different things to different people. It will probably help if we explain the difference between what we at P&B describe as a retrofit and a replacement breaker. In both cases we provide a brand new modern vacuum breaker to replace the original circuit breaker, whether that was an air break, an oil break, or a more recent SF6 or vacuum break device.

In the products you see described on this website as retrofit breakers, this means we start with an original circuit breaker, from which we remove the old breaker, its mechanism and controls. Then we fit a new vacuum breaker into the original truck, comprising some new and some refurbished parts, but fully factory tested and then installed as good as, or often better than, when it was new. P&B retrofits are typically used for air break circuit breakers.

When it comes to bulk oil breakers, P&B provides a complete brand new vacuum breaker and truck, designed and built from scratch to fit directly into the original switchgear housing. The old breaker can be retained in service until the moment the new breaker is ready to be installed and the old breaker can then be disposed of.

P&B Retrofit Switchgear

Vacuum Retrofit for Air Break Circuit Breakers

requires return of original CB truck for retrofit and re-use
COMPANY PRODUCT kV Current, A kA Rating
English Electric E3, E7, E8, HD50 3.6 to 12kV 630 to 3150 25 to 53*
Reyrolle S14 (contactor) 3.6 400 10
S27A,S36A,S45A 3.6 to 12 kV 1250 to 3150 31.5 to 53*
Whipp & Bourne AK (contactor) 3.6 350 10
AH (breaker) 3.6 1600 26

Vacuum Retrofit for Oil Circuit Breakers (Type VOR-M and Type VOR-S)

A complete new circuit breaker is supplied, minimizing downtime.
P&B VOR breakers are the first MV retrofits assessed and accepted by ENA for conformance with all relevant standards for use on the UK electricity supply system.
COMPANY PRODUCT kV Current, A kA Rating
AEI / EE / GEC BVP17, BVP3, OLX, OLX3, KBC, VMX 12 630 to 400 16 to 31.5*
British Thompson Houston JB721/QA 12 630 to 400 16 to 25
Brush Switchgear R4/1, R4/2, VSI, VBA, VBC, VTD 12 630 to 400 16 to 25
Ferguson Pailin FP400, FP 1200, FP 2000 12 630 to 400 16 to 25
Metropolitan Vickers V1R, V2R, QF, QA, MV400 ranges 12 630 to 400 16 to 25
South Wales Switchgear CX, DX ranges, (Hi & Lo type), HG12 12 630 to 400 16 to 25
Statter AC01 12 630 to 1250 16 to 40
Switchgear & Cowans A4, A6, UAE 64 12 630 to 400 16 to 25
Reyrolle LMT, LMT2, LSR 12 630 to 400 16 to 25

Vacuum Retrofit for Vacuum and SF6 Circuit Breakers (Type VOR-M)

COMPANY PRODUCT kV Current, A kA Rating
GEC / ALSTOM VMX 12 630 to 1250 20 to 31.5*
Reyrolle LMV, Hadrian 12 630 to 1250 20 to 31.5*
Brush Switchgear VMV 12 630 to 2000 20 to 40
SWS Hawkgas12 12 630 to 1250 20 to 25
P&B has undertaken a vast range of retrofits to replace oil and air breakers in coal fired and nuclear power stations, utilities and industrial plants, including the steel and petrochemical sectors. See our Case Studies for some examples of our work.

Note: all 25kA VOR-M designs are type tested to cover a short circuit rating of 500MVA (26.2kA rms).

*Several retrofit breakers have been designed and typed tested beyond the ratings proven by the original manufacturer, including recent designs of vacuum switchgear.


P&B is a leading UK innovator of electrical protection, safety and control technologies.

Our specialist expertise and unrivalled experience is relied upon in heavy industries throughout the world to ensure the highest levels of safety and performance.