Generator Phase Load Balance Calculator

Generator Phase Load Balance Calculator

Calculate maximum phase real-power deviation from the three-phase average as a percentage of that average. This defines a kW imbalance metric; it is not voltage imbalance or current imbalance.
Maximum kW deviation from phase average:
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What this calculator measures

Calculate maximum phase real-power deviation from the three-phase average as a percentage of that average. This defines a kW imbalance metric; it is not voltage imbalance or current imbalance.

Inputs and units

Use readings and ratings that describe the same equipment, operating interval, and measurement boundary. The sample entries are editable examples; they do not establish the specifications of your generator.

Input Example entry or choice
Phase A Load (kW) 100 — enter a documented value
Phase B Load (kW) 95 — enter a documented value
Phase C Load (kW) 105 — enter a documented value

Calculation method

First calculate the arithmetic average of the three simultaneous phase real-power readings. Find the largest absolute difference between an individual phase and that average. Imbalance % = largest absolute deviation ÷ average × 100. Zero on all three phases is shown as zero; it describes no real-power demand, not a loaded-system performance test.

Worked example

For 18, 12, and 15 kW, the average is 15 kW and the maximum deviation is 3 kW. The result is 20%. Three equal positive readings produce zero. For 0, 0, and 3 kW, the defined metric is 200%, so this percentage is not capped at 100.

Limitations and checks

Use simultaneous readings with the same sign convention and time interval. This tool accepts nonnegative phase demand and does not analyse reverse power. Different phase power factors mean equal kW readings do not establish equal phase current. Voltage imbalance and manufacturer current limits are separate measurements and requirements.

For a practical decision, keep the original readings, the generator model, the relevant manual or specification, and the assumptions alongside the result. A different load, site condition, rating basis, or unit convention can answer a different question even when the arithmetic is correct.

Sources and methodology

Publisher: CSP Digital Media Ltd. To report a formula, unit, or example error, contact us with the tool name, inputs, displayed result, and expected calculation.

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