PFC Upgrade at Magistrates Court
Power Factor Correction Upgrade at Magistrates Court – South of England
At PFC Engineering, we’re often called in to assess and resolve issues where existing power factor correction (PFC) systems are no longer suitable for the demands of a site. This was recently the case during a scheduled maintenance inspection at a magistrates court in the south of England.
Initial Findings
During our inspection, it quickly became clear that the existing PFC system was not fit for purpose. The installation consisted of a fixed 50kVAr unit, which was insufficiently flexible for the site’s varying load profile.
In addition to this, a more serious issue was identified upstream — the PFC unit was being supplied via a fuse switch that had begun to fail, with visible signs of overheating and burning on the L3 phase. This posed a significant reliability and safety risk, requiring urgent attention.
Load Survey & System Assessment
As part of our standard process, we carried out a load survey while on site to better understand the electrical characteristics of the installation. The results showed that:
- The overall kVAr demand of the site was adequate
- However, the existing correction stage was too large and inflexible
- The fixed nature of the system meant it could not adapt to changing load conditions
This was particularly problematic during periods of low demand, such as overnight and weekends. With the capacitor permanently in circuit, the site was being pushed into a leading power factor, which can be just as undesirable as a lagging one—potentially leading to voltage instability and increased stress on electrical equipment.
Proposed Solution
To resolve both the safety issue and improve overall performance, we recommended a full upgrade of the PFC system.
Key elements of the solution included:
- Removal of the failing fuse switch
- Installation of a new FS100 automatic PFC unit
- Integrated 100A MCCB for safe and reliable local isolation
- Introduction of smaller capacitor stages to allow finer, more accurate correction
To future-proof the installation, the new unit was also specified with detuning reactors. These are essential in modern electrical environments where harmonic distortion is increasingly common, helping to protect capacitors and prevent resonance issues.
Installation & Commissioning
The work was carried out efficiently by a single PFC Engineering engineer, scheduled out of hours to minimise disruption to court operations.
The scope of works included:
- Safe isolation and removal of the failed fuse switch and existing PFC equipment
- Responsible disposal of all redundant components
- Installation of the new FS100 PFC unit in the existing location
- Installation of a new current transformer (CT) circuit for accurate system monitoring
- Full testing and commissioning of the new system
The Result
The upgraded system now provides:
- Accurate, stage-controlled power factor correction
- Improved energy efficiency and reduced risk of penalties
- Elimination of leading power factor during low-load periods
- Enhanced safety with modern protection and isolation
- Increased resilience against harmonic distortion
If your site is running an older or fixed PFC system, it may no longer be suitable for today’s dynamic electrical loads. PFC Engineering can carry out detailed inspections, load surveys, and upgrades to ensure your system is safe, compliant, and operating at peak efficiency.
Get in touch today to discuss your PFC requirements.
