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Why you need
    Power Factor Correction
 

Most electricity suppliers charge on the basis of the energy that is supplied (kVA) to a customer installation and therefore it makes good sense to pay for the electricity you use and not the energy you are supplied. A power factor close to 1.00 will ensure the power bill is as low as possible.

A properly engineered automatic power factor correction system, connected into the main electrical switchboard provides long life and low maintenance with a guaranteed reduction of electricity bill costs.

Power factor correction equipment is suitable for installations that have loadings greater than 200Amps and are charged on a (kVA) "Demand" basis. A power factor of 0.9 or less should be corrected because considerable savings are available. The payback period on equipment used to correct power factor is usually less than 24 months!

The latest technology microprocessor controlled reactive control relays, coupled with the appropriate amount of high quality capacitors can correct the power factor to o.98 or better and ensure the lowest possible electricity costs by eliminating power factor penalties.

The maximum kVA (or kW) and Power Factor are required to enable determination of the required Capacitance (in kVAr) to correct the installation. A check on the distortion levels is also required.

A Power Factor Regulator keeps track of the power factor and

• A single, completely assembled cabinet housing all the appropriate devices (capacitors, contactors and fuses etc.)        Or
• Purpose built sub-assemblies which house all the required components for building into an existing switchboard.

2. Power Factor Correction systems designed for use on installations with high harmonic levels (typically caused by variable speed electronic drives, UPS systems and ARC furnaces etc.) are "de-tuned" using series reactors to create a circuit tuned below harmonic frequencies. As well as protecting the Power Factor system it prevents the PF system from "resonating" with the supply system. A typical tuning frequency is 189 Hz.

Under these circumstances specify capacitors rated minimum 525V 3-phase together with series harmonic de-tuning reactors.

3. Adequate air movement around capacitors is essential for long life operation. Automatic Power Factor Systems above 100kVAr should be forced fan cooled.

Tall and thin cylindrical capacitors, housed in aluminium cases are most suited to the environment and high temperatures in Australia. This design is the most effective method of dissipating heat from the core of the capacitor.

4. Only use the latest technology, self-healing capacitors with low watts loss that incorporate an over-pressure disconnection device and discharge resistors conforming to AS3000.