Following a recent visit to a computer manufacturing site in Warwick, it was found that the existing Power Factor Correction Equipment had a multitude failures. These included, failed capacitors, contactors that had welded closed, and cables that had over heated.


Before Rebuild


The unit itself had never been maintained since its original installation, and now needed repair. It was decided that due to the age of the equipment, and lack of servicing, we would replace the existing trays with our own SBA tray assemblies. This would include all new, long life metallized polypropylene capacitors rated to 480V, new IMO soft switching contactors along with additional sub fusing and new power cables.

The digital control relay was also upgraded to a Lovato DCRL 5, providing more information regarding the PFC as well as advanced functionality over the original one installed on site.

After Rebuild


All work was done in 1 day and site were left fully operating with 400kVAr of new Power Factor Correction Equpitment and an upgraded controller.

Looking for a new challenge? Here at PFC Engineering we are looking to fill roles in both our in house manufacturing as well as our on our site services team.

Please see below for further details and we look forward to hearing from you soon.





Full time positions based near Saffron Walden, Essex.

To assist in the manufacture of Energy Saving Products.

Electrical/mechanical knowledge beneficial but not essential as training provided.

Salary £ Neg (depending on experience).

Please contact PFC Engineering Ltd 01799 530728 or send a C.V to





 Full time positions required within busy maintenance & installation department providing national coverage.

Good electrical knowledge required preferably with 18th edition update.

Full application training will be provided.

Salary £ Neg. plus vehicle.

Please contact PFC Engineering Ltd 01799 530728 or send a C.V to


A recent supply & commissioning for a plastic recycling & manufacturing plant in Hampshire of two 400kVAr Master/Slave detuned Power Factor Correction units with integral door interlocking MCCBs, forced air ventilation and IP54 enclosures


We were asked to attend a large office site in central London to carry out Voltage Optimisation check along with a Thermal Imaging Survey.

Our engineer completed a full maintenance test sheet while onsite taking details regards in the type and method of installation and the unit’s overall condition, along with technical data provided from the units metering cube and collected from other on-site sources.

A thermal graphic survey was then carried out on the Voltage Optimisation unit, checking for any hot spots on the transformer along with checking the supply cables and the bypass switch.

Upon the completion of our testing, it was found that the Voltage Optimisation unit was function correctly and safely. All components were operating satisfactorily, and the thermal graphic tests showed no signs of overheating.

Following on from a recent site maintenance from one of our engineers it was found that the existing panel-built Power Factor Equipment had failed and due to the age of many of the components being over 25 years old it was recommended that a new stand along Power Factor unit be installed. Due to the LV panel having no spare 400A switches it was decided that the new PFC unit was to be connected direct to the bus bars and a new 400A fuse switch would be installed inside the new equipment. This was done during sites next a scheduled LV shutdown.

The unit was close couped to the end of the existing mains panel and connected with new cables to the busbars as well as running a new C.T cable so the unit can see the sites loads.  Once the power was restored to site the unit was commissioned and left operating.

The New Power Factor unit consists of 2 stages of 25kVAr and 3 stages of 50kVAr, controlled by a 5 stage Lovato digital control relay. Having different sized capacitor stages allows the unit to provide finer correction at lower loads and the digital controller lets site to view information regarding the health of the Power Factor along with other readings such as KW, kVAr & KVA.

Recently we were asked to visit an aggregates site in East London to carry out commissioning on this 300kVAr automatic, detuned Power Factor Correction Unit. Site had just had the mains LV panel upgraded along with the local Transformer.

The PFC unit was fully maintained by our engineer and the control relay settings were checked to make sure it was set up correctly. After a bit of a clean out and the tightening of a few loose terminals the unit was switched on and left operating satisfactorily.