When properly sized for an application, it is not uncommon for Zero-Max Drives to have an operating life of 15,000 to 20,000 hours or more.  In addition to using a service factor when sizing, starting and accelerating the output load slowly or starting at zero speed and gradually increasing the output speed will minimize stress on the Drive and further extend lifetime.  Shock loads or jam-ups on the connected equipment can create torque spikes and overloads that can shorten lifetime.  If shock loads or overloads are anticipated in the application, use of a torque limiting device on the output of the Zero-Max Drive is recommended.