Emergency generators are often called into service during catastrophic events like hurricanes, floods, tornadoes or fires, but also during more mundane events like thunderstorms and other things that may temporarily interrupt the public power grid. Can you rely on your generator to perform at those critical times?
Many industries, government buildings, hospitals or other public facilities are equipped with fixed backup generators to provide power for critical operations. Failure of the generator to automatically start and function normally can have costly consequences. It is therefore necessary that a program of maintenance and testing be regularly performed on backup generators to improve the chances that they will perform as expected.
Most fixed generators in industries and public facilities are powered by Diesel engines. Diesel engines are ruggedly built and long-lasting. However, there are some peculiarities unique to these engines that require meticulous attention to details.
For example, engine failure can occur in as little as 250 operating hours if the proper coolant is not used and maintained. Additives in the coolant coat the surfaces of the cooling jackets to provide protection against cavitation erosion, which can cause pitting of the cylinder liners. If such damage progresses to the point that coolant leaks into a cylinder, the engine will overheat due to loss of coolant, if the leak occurs during engine operation. The engine will shut down when overheated. A more catastrophic failure will occur if coolant leaks into a cylinder and accumulates when the engine is not operating. When an attempt is made to start the engine when coolant has accumulated in a cylinder, the result is usually a bent rod and sometimes a fractured engine block. This damage occurs due to hydraulic lock, or an attempt to compress an incompressible liquid.
A second example is a fuel-related failure of a Diesel engine. Hydrocarbon fuels that are stored for a time before use may suffer microbial contamination. This problem may be exacerbated by the increased usage of biodiesel fuel, but can occur in any petroleum product. Contamination of fuel can cause fouling of tanks, pipes, filters and corrosion of tanks. One of the primary reasons that generator manufacturers recommend a schedule for “exercising” their Diesel generator sets is to use up the stored fuel to ensure that contamination issues are minimized and fresh fuel is available for reliable operation. Fuel contamination can cause blockage in the fuel system of a Diesel engine, rendering it non-operational just when you need it most.
If you have experienced an engine failure or other loss due to the failure of a generator set to function, engineers at Warren are available to determine the cause, enabling you to take steps to prevent such costly occurrences.
Roger Davis, a senior consulting engineer at The Warren Group, is a licensed professional engineer in South Carolina, North Carolina, Alabama, Georgia and Mississippi. He holds a Bachelor of Science in Mechanical Engineering and a Master of Business Administration from the University of South Carolina. Roger is a certified fire and explosion investigator and certified vehicle fire investigator. He is an accomplished gas and diesel engine mechanic and has more than 30 years of experience with hydraulic plumbing and piping issues. His expertise also includes property damage and personal injury investigations involving municipal utilities. Roger has investigated claims and injuries ranging from pressure piping system failures and material and personnel handling equipment to large engine failures and fires involving machinery, generators and vehicles.