Surge Capacitor Informations

A surge capacitor is a device designed to absorb surges and/or reduce the steepness of their wave front. A capacitor is able to absorb and hold a charge of electricity, returning it to the circuit at a later time. Since the surge capacitor is always connected to the power circuit, current flows at all times. When a surge occurs, added current flows to the capacitor thereby lowering the intensity of the surge voltage. The amount of current the capacitor can absorb depends on the size of the capacitor, and the amount of voltage pushing the current.

If the surge is of a low current relative to its voltage intensity, the capacitor will absorb it. If the surge has high current, the capacitor cannot absorb it.

The main advantage of a capacitor is that there is no time delay in turning on as it always conducts. The disadvantage is that the amount of current it can handle is limited to a few amps, depending on the surge voltage. For this reason, an arrestor should always be installed with a capacitor to protect it from intense surges.