This is your own personal Cheat Sheet for calculating demand (kW)
| Key
kW = Kilowatt (Demand) kWh = Koliwatt Hours (Energy) I = Current I1 = Phase 1 Current V = Voltage W = Wattage pn = Phase to Neutral pp = Phase to Phase |
|
| Basic kW Calculation
The most basic calculation for demand |
kWh ÷ Hours = kW |
| Calculating Demand from Pulses
If you are trying to calculate Instantaneous Demand and have a pulse meter, try this equation |
kWh / Pulse x 3,6000 sec/hour —————————————— = kW # of seconds between pulses |
| Single-Phase Calculation
Most Single-Phase applications will be for Residential and Small Commercial buildings |
I x V = W
W ÷ 1,000 = kW |
| Balanced 3-Phase Power Measurement
Use if all 3 Phases pull the same amount of current |
I x Vpp x 1.73 = W
W ÷ 1,000 = kW |
| Individual 3-Phase Current Measurement Phase to Neutral, Use if the Phases pull different amounts of current. Most simple calculation for these conditions |
(I1 + I2 + I3) x Vpn = W
W ÷ 1,000 = kW |
| Individual 3-Phase Current Measurement Phase to Phase, Another method of calculating Demand if the Phases pull different amounts of current |
(I1 + I2 + I3) x Vpp x .577 = W
W ÷ 1,000 = kW |