[M.D. Holloway]

Red - great study!

Take a look at this. I used to do energy use surveys and here is how I calculated it. Was this OK?


Record Amps:
For 3 Phase 460 or 480 Volt, Average Brown, Orange, Yellow Legs
For 3 Phase 208 or 230 Volt, Average Black, Red, Blue Legs

What are the Volts: (Typically 3 Phase, 460)

Determine the Power Correction Factor.
Unless a Power Factor is determined, a value between 0.85 (older or larger motors >2hp) and 0.91 (newer or smaller motors <2hp) is acceptable.

Calculate kVA in Order to Determine
kWatt Usage:
kVA = Volts X (Averaged Amps X 1.732) / 1000

Convert kVA to kWatt
kWatt = kVA X Power Correction Factor

Annual Hours of Operation for Motor
Daily Hrs X Days per Wk X Wks per Yr
(8 hour shift, 5 days/wk, 50 wk's/yr = 2000 hours)
(24 hour shift, 7 days/wk, 52 wk's/yr = 8736 hours)

kWatt Hour Rate
National Average is $0.06 kW-hr

Calculated Annual
Energy Costs
(kWatt X Hours of Operation X kWatt $Rate)