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Running cost of an electric motor

Running cost of an electric motor

Running cost of an electric motor

(OP)
Can anyone give a formula for the running cost of an electric motor from a three phase supply 24/7 for a year   

RE: Running cost of an electric motor

watts x hours /1000 = kWh, which is what your utility bills you for.

Methinks you were looking for something else, but of course your question was a little sparse on details. Are you unable to measure the kW consumption? Isn't there a load connected to your motor? Are you looking to estimate cost based only on motor nameplate data?  Does your utility penalize you for poor power factor? Are you going to correct your pf? The list goes on and on.

Eng-Tips: Help for your job, not for your homework  Read FAQ731-376

RE: Running cost of an electric motor

Well said jraef
damscot, Try browsing this site. This topic was discussed in great detail within the last few weeks.
yours

RE: Running cost of an electric motor

Demand 1 Start per month (KW) plus energy (KWHrs)

RE: Running cost of an electric motor

Damscot.
The requested formula for 1 year motor operation:

   E = 1.732xAmps x VoltsLL x PF x 24(hrs) x 365(days)
     Cost = E x $(per 1kWH)  


E = Total electric energy consumption in 1 year given in kWH.
Amps = average RMS line current of the three phases.
VoltsLL = average RMS voltage line to line(3 phases)
PF = motor power factor on the nameplate or from the motor manufacturer performance data.

Penalties due to maximum demand and excesive low power factor will add some extra cost depending on the utility regulations.

RE: Running cost of an electric motor

If the motor is running at less than 100% load, the power factor will have to be determined at actual operating conditions instead of using the nameplate value, unless the power factor has been corrected to 100%.
respectfully

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