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PFC Replacement – Gym, Newcastle upon Tyne

Initial Findings

During a maintenance visit, the site’s existing power factor correction (PFC) equipment was found to be in a failed state. The following issues were identified:

  • 4 x 125 A DIN fuses had blown, leaving the system unprotected.
  • All 50 kVAr capacitor stages had failed, rendering the PFC system completely inoperative.
  • Given the age and condition of the equipment, an end-of-life replacement of all major components was strongly recommended.

For safety, the defective PFC unit was isolated and left offline, awaiting replacement works.

Replacement Works

A new modular PFC system was designed and installed as a like-for-like replacement for the original ABB equipment. The new trays were engineered to fit directly into the existing framework, allowing:

  • Reuse of existing power leads
  • Retention of original tray fixing points
  • Minimised installation downtime and site disruption

The replacement system incorporates several modern upgrades:

  • Soft-switching contactors – providing smoother capacitor engagement and reduced electrical stress.
  • 480 V rated capacitors – ensuring higher durability and better tolerance to supply variations.
  • Lovato DCRL5 fully digital controller – replacing the outdated relay with an advanced unit offering improved monitoring, automatic step adjustment, and greater accuracy in reactive power management.

Performance Outcome

Following installation, the PFC system successfully restored site efficiency. The gym’s power factor improved from 0.81 inductive to unity (1.00), eliminating excess reactive power demand and significantly reducing the risk of utility penalty charges.

The upgraded PFC not only restores compliance but also delivers:

  • Improved energy efficiency
  • Reduced strain on electrical distribution equipment
  • Extended lifespan of connected plant and machinery
  • A more stable and resilient electrical supply for the site’s daily operations

 

 

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PFC Upgrade at Community College, Crawley

During a planned maintenance visit to the college’s LV distribution system, engineers discovered a complete failure of the existing power factor correction (PFC) equipment. All six 25 kVAr capacitor units had failed, and four 100 A DIN fuses were found to have blown. This failure left the site operating with no functional PFC, increasing the risk of higher reactive power charges and potential strain on the electrical infrastructure.

A detailed site load test was carried out to establish the actual reactive power requirements under normal operating conditions. The results confirmed that a total of 100 kVAr correction capacity would be more than sufficient to consistently maintain a site power factor above 0.96, comfortably within recommended efficiency standards.

To modernize and simplify the installation, the three failed ABB 25/25 kVAr modules were decommissioned and removed. These were replaced with a single 100 kVAr SBA tray, configured with four independently switched 25 kVAr soft-switching steps. This modular setup ensures greater flexibility, smoother operation, and reduced electrical stress compared to the original equipment.

In addition, the outdated reactive control relay was upgraded to a fully digital Lovato DCRL5 controller. This modern unit provides advanced monitoring, automatic step regulation, and improved accuracy in managing reactive power demand.

The upgrade not only restores reliable PFC capability but also improves system efficiency, reduces electrical losses, and minimizes the likelihood of future reactive energy penalties.

 

     

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Panel Built Detuning Trays for Fresh Food Factory

Following a review of the load at this large UK food manufacturer, it was found that the standard Power Factor Correction equipment was beginning to elevate low levels of background harmonics above 3% VTHD, causing premature failure of the capacitor banks. Due to space limitations, it was decided to remove all the existing standard PFC components and replace them with our fully detuned 189Hz PN54 Trays.

 

Each tray consists of 1 detuning reactor, a soft switching 415V contactor and a 50kVAr 480V rated capacitor bank. As well as the new tray assemblies, we also upgraded the control relay to the more reliable fully digital Lovato DCRL5 and installed additional forced air ventilation to help keep the reactors cool while under load.

With 2 units being rebuilt the same way, all works were carried out by a single engineer over 2 days without any disruption to the site’s load.

 

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FS300 Power Factor Unit Install at Brick Factory

We were asked to carry out a service of a Power Factor Correction unit at a Brick Factory near Huntingdon, UK, that had no previous service history since its installation in 2011.

During our investigation, we found multiple failures of the internal components including failed capacitor banks, contactors that had welded themselves closed, multiple fuse failures and a high amount of dust and debris inside the cubicle.

Due to the high amount of failures, high levels of dirt and lack of annual servicing we recommend an end-of-life replacement of the PFC panel with a new FS300 Unit.

The new power factor unit would consist of 5 x 50kVAr capacitor stages and 2 x 25kVAr stages allowing for finer correction at lower loads. Incorporating high quality, long-life metallized polypropylene capacitors (480V rated) with over-pressure disconnection devices and discharge resistors fitted.

The unit would also include a built-in 630A load break switch and forced air ventilation.

 

Using the existing power and C.T cables the old unit was stripped down and removed from the site and the new FS300 was placed in the same position as before at the end of the LV panel. When in operation the unit would bring the site’s power factor up from 0.80 indictive to unity with 200kVAr of capacitors in circuit.

 

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PFC Unit upgrade at the supermarket

An end-of-life replacement was required for an old Power Factor Correction unit at a supermarket in central London.

A new wall-mountable FS100 PFC unit was to be installed using the existing power and C.T connections. The unit would incorporate 4  25kVAr capacitor banks, 480V rated with IMO MC32 soft switching contactors, sub fusing and additional forced air ventilation.

 

The unit would be controlled via a local Lovato DCRL 5 digital control relay and also include an integrated 200A load break switch for local isolation.

 

When operating the site power factor would be improved from 0.81 inductive to a unity power factor helping to save money on the monthly electricity bills by removing any reactive charges.

 

This unit was installed in 1 day by 1 engineer during normal working hours without any disruption to the site’s supply.

 

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PFC Tray Assembly Replacement at Meat Factory.

This 350kVAr Power Factor Correction unit installed in 1998 was found to have multiple capacitor failures following a long period of not being annually maintained.

It was decided that an end-of-life replacement for all the tray assemblies would be the best option. As such we swapped out the old-style SBA trays with its cascaded contactor steps with a more modern SBA tray with two 50kVAr soft switching contactors on each and 480V-rated capacitors.

We also included a smaller tray with two stages of 25kVAr for finer correction at different loads.

As well as this we also installed forced air ventilation into the front of the panel to help regulate the internal temperature of the unit.

 

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PFC Replacement at UK Rubber Manufacturing Plant

We were asked to carry out a full maintenance of a panel built Power Factor Correction unit at a UK rubber fabrication plant.

The existing PFC on site had not had a full service before despite being installed in 1997. The unit has a multitude of component failures including the failure of capacitor banks, contactors that had welded closed, burnt-out inrush coils and operated fuses.

Due to the age of the equipment and the lack of annual servicing we recommended an end-of-life replacement to the panel and the installation of a new FSi200 fully detuned PFC unit.

The new unit would consist of 3 stages of 50kVar and 2 smaller stages of 25kVAr all controlled by an 8 stage Lovato DCRL 8 digital control relay. We would also include additional forced air ventilation and filtered louvres.

Due to the construction of the existing panel, we were able to remove the PFC section entirely and put the new unit in its place. New power cables were installed and connected to the existing MCCB that fed the old equipment.

 

All the works were carried out by 2 engineers during normal working hours without any disruption to the site supply.

 

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PFC Detuning for a Large Fizzy Drink Manufacturer

After a callout to a significant capacitor failure inside one of the Power Factor correction units, it was noted that the background harmonics had increased since our last annual service visit.

A week-long Power Quality Analysis was carried out on both LV supplies on-site and from the results it was confirmed that there was a notable increase in the load current and harmonic current distortion on the supply during the period of higher occupancy, this was in part due to the recent installation of multiple EV chargers.

The level of voltage harmonic distortion on both supplies was such that the original standard power factor correction equipment on site was magnifying this distortion when in circuit and as such now requires the incorporation of harmonic detuning reactors to prevent harmonic overload of the PFC capacitors.

The solution was to remove the existing PFC units and replace them with two fully detuned FSi200 units incorporating 480V capacitors, soft switching contactors and 189Hz reactors; utilizing the existing cable and C.Ts.

 

All the works were carried out by 2 engineers over 2 days without any disruption to site.

 

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Power Factor Unit Replacement

A recommendation for an end-of-life replacement for a 100 kVAr ABB PFC unit was made following site’s annual maintenance due to the age of the existing equipment as well as multiple capacitor failures.

We also recommended adjusting the capacitor step sizes to be more suited to the site’s current load conditions.

With this in mind, a replacement FS200 was to be installed consisting of 2 x 13.5kVar capacitor stages and 2 x 25kVar capacitor stages along with its own integral interlocking load break switch for local isolation and fully digital Lovato DCRL 5 control relay.

 

Utilizing the existing power cable and C.T. circuit our engineer removed the failed unit and installed the new FS200 in the same location at the end of the main panel. The works were carried out during normal operating hours and did not affect the operation of the site.

 

   

 

          

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PFC Replacement at Highstreet Supermarket

 

This old 100kVAr Power Factor Correction unit had reached the end of its life expectancy and multiple internal components had started to fail. It also had very little to no annual servicing carried out on it and due to its location inside an external GRP container, it had also started to rust.

Following an on-site load survey carried out during the maintenance visit, it was confirmed that the 100kVAr was sufficient to reach a healthy power factor of 0.99 inductive and the site background harmonics were below 2%VTHd.

The unit was replaced with one of our standard FS100 fully automatic PFC units including all new 480V rated capacitors, soft switching contactors and a fully digital Lovato DCRL 5 control relay.

 

As the unit was being fed from its own dedicated 250A MCCB all the works could be carried out during normal working hours with no disruption to the site.

 

 

      

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PFC FSi300 Rebuild

Following a maintenance request from a large aggregate manufacturing plant just outside London we carried out a service on what turned out to be one of our Power Factor Correction units, a FSi300 originally built by us in 2007 for a 3rd party installer.

The unit had never been serviced since installation and due to its dusty environment years of accumulated dirt had built up in and around the unit which eventually led to the site isolating the unit in 2020 where it had been left ever since.

 

During our service, we found multiple capacitor failures along with lots of rust on the detuning reactors. All the ventilation fans in the roof had also seized and the unit’s key had ben lost.

Due to the failures and lack of servicing the best option was to replace the internal trays with new ones, including all capacitors, contactors and fuses. Along with this we also replace all the fans in the roof and upgraded the control relay to the latest Lovato DCRL range.

 

Upon completion, the site had improved its Power Factor from .041 inductive to 0.99 with all works being carried out during normal working hours without any disruption to site operation.

 

 

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Detuned PFC Replacement in Central London.

We were asked to carry out a survey with the intention of replacing 1000kVAr worth of failed PFC equipment at a large office building in central London. Upon our initial visit to the site we found that the existing Power Factor Equipment had suffered some major component failures due to lack of servicing which had consequently led to a small fire and the units being isolated by the site.

 

The two PFC units on site, each on one supply, were split into a Master/Slave configuration with the existing mains cables coming into an expansion box on the side. These cables were still satisfactory and to help the customer keep costs down it was decided that they were to be re-used for the new equipment.

 

The new units would be from our FSi Deep range and consist of 2 stages of 30kVAr and 7 stages of 60kVAr each with its own 189hZ detuning reactor all controlled by a 10-stage Lovato Digital control relay.

 

Due to the location of the LV panels being on the roof of the 12-story building, once the new PFC panels had been built and tested the detuning reactors were removed to help reduce the total weight of the units making them more manoeuvrable for our engineers. Once the units were positioned the reactors were re-installed and the panel re-tested.

 

The installation took 4 engineers 2 days during normal working hours with no disruption to the site, and all waste was removed and disposed of as required. On the 3rd day, an engineer returned to commission the new panels and carry out some final tests.

 

 

                 

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