EleCanada
Loads and electrical power

Connected load calculator

Total electrical input loads at one voltage and phase arrangement, including loads with different displacement power factors. This is not a dwelling service-load or demand-factor calculation.

Calculation inputs

Load group

V RMS

One common voltage for all loads. Three-phase uses line-to-line voltage. Do not combine mixed-voltage or unbalanced single-phase loads.

For each nonzero load, enter its displacement power factor and whether current leads or lags. The calculator combines real and reactive power at a common voltage.

Load 1
kW each
0–1

Enter a decimal displacement PF. This is not total PF for a distorted waveform.

Enable JavaScript to edit the list and calculate.

Connected load

Enter the group details and at least one complete load.

All listed loads operate together with the entered displacement PF and lead/lag direction. No diversity, demand factor, starting allowance or protection margin is applied.

What it calculates

Enter each load's electrical input kW and quantity, not motor shaft output or breaker rating. The calculator multiplies each row's input power by quantity, then totals the rows. Names are optional labels and do not affect arithmetic.

This list is for single-phase loads at one common RMS voltage, or balanced three-phase loads sharing one line-to-line voltage and phase arrangement. Each load may have its own sinusoidal displacement power factor and leading/lagging direction. Mixed voltages, unbalanced single-phase phase assignments and harmonic-rich loads need another model. The list stays in the page and is not saved or transmitted.

Method and example

For each row, Pᵢ = quantity × input kW and Qᵢ = Pᵢ × tan(arccos(PFᵢ)); lagging Q is positive and leading Q is negative. Sum P = ΣPᵢ and Q = ΣQᵢ, then S = √(P² + Q²), combined PF = P/S, and single-phase current I = 1000S/V or balanced three-phase line current I = 1000S/(√3 × V). V is RMS, and three-phase V is line-to-line.

A 4 kW load at PF 0.8 lagging and a 3 kW load at PF 0.8 leading contribute 3.00 kVAr and −2.25 kVAr, respectively. The group totals 7 kW and 0.75 kVAr, about 7.040 kVA. At 240 V single-phase this is about 29.334 A and combined PF 0.994 lagging. This is arithmetic for simultaneous sinusoidal operating points, not sizing advice.

Arithmetic retains numeric precision; display rounds to three decimals and uses scientific notation for very small or large values. A zero-kW row contributes zero and does not require PF or direction.

What this does not decide

The result is connected-load arithmetic, not a CEC dwelling-load worksheet, service capacity approval, demand analysis or generator/motor-start estimate. No code demand factors, continuous-load allowances, manufacturer derating or spare capacity are included. Do not choose a breaker, conductor, panel or service rating from this result alone.

Common questions

Can I list different power factors?

Yes, when each value is a sinusoidal displacement PF for the same operating condition and its lead/lag direction is known. The model adds their real and reactive components; it does not combine distorted-waveform total PF or harmonic spectra.

Can I list loads from different phases of a panel?

Do not combine unbalanced single-phase branch loads and call the result a balanced three-phase current. The phase arrangement must match the entire load group.

Why do results disappear after I change the list?

The displayed total no longer represents the edited inputs. Recalculate to obtain a result for the current group.

Electrical calculator converts a single known power/current quantity or solves an ideal DC resistive load.

Electrical relationshipsSolve DC quantities, convert AC power/current, compare PF current ratios, or relate balanced wye voltages.Transformer currentCalculate transformer line currents or kVA from rated data.Three-phase neutralSum sinusoidal phase currents with displacement PF.

Source

Natural Resources Canada, Variable Frequency Drives, Appendix D, “Power in AC Circuits”, checked November 11, 2026. Its sinusoidal power-triangle, PF and current relationships support the row power decomposition and combined apparent-power conversion. Exact √3 replaces the guide's rounded three-phase factor. No jurisdictional acceptance rules are taken from this source.

Report a problem or suggest a source. Your load list is not included automatically.