High endurance capacitors are critical in the service life of any harmonic related device. The harmonic current that flows through any harmonic filter is extremely harsh and hard on electrical components. Early in the development life of the first harmonic filters it was found that a high endurance or harmonic rated capacitor were critical to ensure long service life. Standard power factor correction caps or motor starting caps are a poor way to protect the service of your filter and your drive system. While the high endurance capacitor is considerably more expensive, it has been found to be an important component that can be a great cost savings to the end customer down the road.