Correction gear is often specified for the worst case and then runs half loaded. These five checks usually recover most of the benefit at a fraction of the cost.
Correction gear is often specified for the worst case and then runs half loaded for most of its life. Before ordering a larger bank, it is worth checking whether the existing equipment is actually being used well.
Start with the load profile, not the nameplate
Power factor correction sized against peak demand alone tends to overshoot during normal operation. Log the load over a representative week before deciding on a capacitor step size.
- Match capacitor steps to the actual swing in reactive demand, not the theoretical maximum
- Check for harmonic distortion before adding capacitance — it can resonate with existing filters
- Inspect contactors and fuses for wear; a failing step often masquerades as undersizing
- Re-balance switching stages so no single step carries a disproportionate share
- Confirm the controller's target power factor is realistic for your tariff, not just as high as possible
Most sites recover the bulk of the available benefit from these checks alone, well before a larger bank is justified.
