FRAKO Germany Power Capacitors enclosed in a Sheet Metal Enclosure with Busbar and Cable entry arrangement for easy cable connection along with MCB for protection purpose enclosed in a sheet metal enclosure with busbar and cable entry arrangement for easy cable connection.
Miniature Circuit Breakers (MCB) is used for protection purpose. The MCB tripping is an indication of whether the circuit has been overloaded or that a short-circuit has occurred in the System. MCB is selected with tuned tripping characteristics to ensure the inrush current of the capacitors will not cause any inadvertent tripping of the MCB.
Capacitor application Breaker needs to have faster opening time to avoid restriking between the contacts. In the case of MCB, the opening time by the tripping mechanism is independent of the operation. The present generations MCBs are built-in with current limiting features, thus partially damping the inrush current.
Capacitor Banks needs to be switched ON & OFF manually using a proper Switching Devices.
Inrush Current of the parallel connected Capacitors needs to be considered for selection.
Capacitor Banks can be selected for the load centre with several inductive loads operated together where Loading pattern is constant.
Level of Harmonics is within the guidelines for harmonics.
Cable size not suitable to connect individual capacitors.
Capacitor Duty Contactors:
The Contactors being the only moving component, necessitates careful selection for this application to ensure longer life for these contactors. Due to the characteristics of the capacitor operations and necessity to restrict the inrush current by using a suitable damping resistor which shall be in the circuit only for a short duration (during the in-rush current phenomena), a careful selection of the Capacitor Duty contractors with built-in Damping Resistors is required, considering the transformer impedance and the number of capacitors operating in parallel.
Capacitor Duty contractors, which has two sets of contacts, one for restricting inrush current and other set is for continuous loading of the capacitors. This capacitor duty contactor is specially designed with the damping resistance which restricts the inrush current. We will be using specially designed Capacitor Duty contractors with Damping Resistors. These types of contractors are different from standard contactors.
In automatic switching, the capacitor Bank is switched through control contactor energized through the motor controls and switched after a fixed delay. The switching is done through capacitor duty contactors, and push buttons.
Switched Capacitor Banks can be selected for the load center with several inductive loads operated together where:
Loading Pattern is constant.
Level of Harmonics is within the Guidelines for Harmonics.
Cable size not suitable to connect Individual Capacitors.
Require manual / automatic operation of the capacitors by the user