Load banks are devices designed to provide power draw in order to test power sources such as generators and Uninterrupted Power Sources (UPS). Testing with a load bank allows to run auxiliary power systems under load in order to verify performance reliability in case of an emergency. Load banks eliminate the risk of total power loss and power quality loss in a critical facility load. Another important reason to perform load bank test is to prevent Wet-Stacking. Wet stacking is a common issue occurs when diesel engines are ran for prolonged periods of time under low load or in idle. When diesel engine runs without enough load, it will not perform at optimum temperature and efficiency. An engine with wet stacking problem will require more maintenance and reduce performance. In order to help minimize the effects of Wet-Stacking, it is advised to periodically use load banks in order to run the generator where there isn't enough electrical load. National Fire Protection Association (NFPA) suggests load bank tests alongside periodic maintenance.