On the nameplate of each engine two important parameters are indicated: Efficiency and cos φ. They directly affect your energy bills. Let's figure out what they mean in simple words.
What is efficiency
Efficiency (coefficient of performance) shows what proportion of the consumed electricity is converted into useful mechanical work. For example, an efficiency of 90% means that 90% of the energy goes into motion, and 10% is lost in the form of heat in the windings and steel.
The higher the efficiency, the less the engine “eats” excess electricity. It is the efficiency that underlies the energy efficiency classes IE1–IE4.
What is cos φ
The power factor cos φ shows how efficiently the motor uses current from the network. Part of the current does not do useful work, but only creates a magnetic field (reactive power). Low cos φ means that more current flows through the network than is needed for operation.
| Parameter | What it shows | The higher |
|---|---|---|
| Efficiency | Share of useful energy | Less heat loss |
| cos φ | Current efficiency | Less excess current |
Why is this important
- A high-efficiency motor saves energy during round-the-clock operation.
- Low cos φ leads to fines for reactive power in enterprises.
- Improper repairs can reduce efficiency - quality matters rewinding.
Interesting: poor-quality rewinding with a violation of the number of turns or wire cross-section worsens the efficiency and cos φ. Therefore, exact adherence to the parameters during repairs pays off in energy savings.
Do you need rewinding without loss of efficiency in Tashkent? Elektromotors engineers comply with factory parameters - leave a request.