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Do full-voltage starts raise power bills?

Q: Is it true that a full-voltage start on my compressor motors will significantly increase my electrical bill compared to soft starts or Star Delta, Wye Delta, etc., because of the power spike?

A: Generally this is not true, but it's often touted by over-zealous marketing/sales personnel who use these soft-start controls on their compressor packages.

The usual demand change is based on a high average kW reading taken over a 15- to 30-minute time frame. The power spike we are discussing is 1 to 2 seconds in duration. The soft starts generally experience 50 to 70 percent of the power spike of Full Voltage, for a duration of 3 to 7 seconds.