Power factor correction unit
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A power factor correction unit is equipment used to improve power factor, in industrial networks. It usually consists of a number of capacitors that are switched by means of a contactor. These contactors are controlled by a regulator (digital varmetric relay), that measures power factor in an electrical network. To be able to measure 'power factor', the regulator uses a CT (current transformer) that measures the current in the 1st phase (3-phase network), usually a CT is chosen with a primary current adapted to the network current, and a secondary current of 5 amps (depends on the regulator).
Depending on the load and power factor of the network, the regulator will switch the necessary steps to make sure the power factor stays above 0.9 (which is usually demanded by the energy supplier).
Legend:
- 1. Regulator
- 2. Network connection points
- 3. Fuses
- 4. Contactors
- 5. Capacitors (single-phase units, delta-connection)
- 6. Transformer 400/230 Volts for auxiliary tension (contactors, ventilation,...)
