A 500 kW load running at a costly 0.75 power factor — sized up to a 277 kVAr delta-connected capacitor bank that cuts line current by a fifth.
| Active load | 500 kW, 415 V three-phase |
| Existing power factor | 0.75 |
| Target power factor | 0.95 |
| Bank connection | Delta, rated at 440 V |
| Check | Requirement | Actual | Status |
|---|---|---|---|
| Required capacitor bank rating | n/a (this is the sizing result) | 276.6 kVAr | ✓ PASS |
| Line current after correction | n/a (informational) | 732.2 A, down from 927.5 A | ✓ PASS |
Key insight: Power factor correction reduces current and apparent power without changing the actual real power (kW) the load consumes — the load still does the same 500 kW of work, but the supply, transformer and cables no longer have to carry the extra reactive current that was previously going back and forth to support that load's magnetizing/reactive needs.
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Open Power Factor Correction calculator →Capacitor banks are typically rated with some margin above nominal system voltage to account for normal voltage variation and harmonic voltage content, both of which stress a capacitor more than a purely sinusoidal signal at exactly nominal voltage — running a capacitor at or above its rated voltage for extended periods accelerates dielectric aging and shortens its service life.
Not usually — pushing power factor all the way to 1.0 requires a larger capacitor bank for diminishing improvement, and slight over-correction can actually create a leading power factor during light-load periods (when the fixed capacitor bank's reactive output exceeds the load's now-smaller reactive demand), which many utilities penalize just as they penalize a lagging power factor. Most utility tariffs and this calculator's own target-PF convention aim for a value like 0.95, not 1.0.