Industrial Engineer · phase 9 of 16 · noun
Motor Power Factor
Ratio related to real and apparent motor power that may be entered for motor identification or control calculations.
The Explain card
- Plain English
- Power factor is how much of the motor's current is doing real work versus magnetising the iron. It is a number below one on the plate, often around 85 percent for a mid sized induction motor.
- Example
- A drive setup screen asks for the nameplate power factor. Entered, it helps the drive separate torque producing current from magnetising current in its motor model.
- Why it matters
- Behind a drive, the plant supply no longer sees the motor's power factor at all, only the rectifier's. The number matters for the drive's internal model and for sizing any motor side equipment, and it is one more plate value that a default silently gets wrong.
- Hook
- How much of the current is actually turning the shaft.
Word knowledge
How the word is built, where it came from, and what it sits beside in memory.
In a sentence
During VFD commissioning, enter the Motor Power Factor from the nameplate into the drive's motor-data parameters.
Why these words
- motor Latin motor, mover narrows the phrase to motor equipment
- power Old French poer, ability or strength places the phrase in electrical-power terminology
- factor Latin factor, maker or doer supplies the phrase's head noun and technical label
Where it came from
- Origin
- English compound formed from motor and the established electrical term power factor
- Entered the language
- 20th century
- What changed
- Factor moved from a maker or agent to a mathematical quantity, then entered AC engineering terminology; motor later specified the equipment to which the term applies.
How it is spelled
- Pattern
- The phrase is an open compound with three separately written words.
- Pattern
- Power keeps the ower spelling heard with the same vowel in tower and flower.
- Pattern
- Motor and factor both keep the Latin-derived or ending.
Spelled like
- tower
- flower
- rotor
- stator
Broken into chunks
-
motor
- motor current
- motor torque
-
power
- power circuit
- power quality
-
factor
- service factor
- demand factor
What it sits beside
Same subject
- motor nameplate
- apparent power
- variable frequency drive
- motor commissioning
Same shape
- motor current
- motor voltage
- service factor
- power quality
motor nameplate entries
- rated voltage
- rated current
- rated frequency
- Motor Power Factor
AC power terms
- real power
- reactive power
- apparent power
Where it sits in the deck
Phase 9: VFD Ratings, Sizing, and Motor Data
Nameplate arithmetic, where the currents, voltages and duty ratings decide whether a drive can actually run the motor you bolted it to.
