Why You Need Capacitor?
Most of the power distribution authorities have a requirement of high power factor for lighting fittings of generally 0.85 to 0.90 minimum.

A typical Fluorescent circuit without power factor correction has an inherent low power factor (around 0.4 to 0.5), due to the control gear inductance. This inductance is in the circuit to stabilize the pulsation of the current passing through the lamp. As in the case of lighting fittings where many lamps are used, high input current is recorded thus high cost of electricity.

The inclusion of a Capacitor which has an opposite effect of an inductor can raise the power factor and reduce the current drawn from the mains. This will result in savings in electricity cost and equipment cost in terms of reduction in copper and transformer size.

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