Load Banks

Load banks are an important part of emergency backup and prime power systems. They are essential for testing, verifying, and exercising a power system’s ability to handle a required electrical load and are increasingly being used as an essential tool to maintain generator reliability in applications where exhaust aftertreatments are necessary to meet emissions standards.


Testing, Verifying and Exercising Power Equipment

Load banks are a key element in ensuring that an emergency backup power system can handle the required electrical load in the event of an actual utility power failure. Load bank testing simulates an electrical load and applies it to the backup power system. This can test everything from the automatic transfer switch (ATS) to the diesel engine and alternator, to make sure the entire system is operating properly.

To meet certain code and maintenance requirements, backup power generators must regularly be tested and exercised. The National Fire Protection Association (NFPA) has set requirements regarding acceptance testing and periodic on-site testing and maintenance of emergency and standby power systems. It is required that emergency and standby/backup power systems be tested and verified under load, and this is accomplished using a load bank.

Load Banks for Diesel Generators with Exhaust Aftertreatments

With the increasing use of aftertreatments including diesel particulate filters (DPF) and selective catalytic reduction (SCR) to meet diesel generator emissions standards, load banks play a vital role in maintaining generator reliability. Without a load bank installed, diesel generators with aftertreatments may run for a time, but the aftertreatments can cause back pressure to build up and cause internal alarm systems to shut down the generator. A load bank alleviates this problem by applying the proper electrical load to the generator, allowing it to operate at the temperatures needed to eliminate back pressure build up.

Even without aftertreatments, load banks are often installed on diesel generators to apply additional electrical load so that the fuel is fully consumed. When diesel generators are operated at less-than-ideal loads, the engine does not work hard enough to burn all the fuel, that unconsumed fuel collects in the exhaust system and over time can create a problem know as ‘wet stacking’. Load banks have long been used to eliminate reliability issues due to wet stacking.


Load Bank Brands


To meet various power system applications, load banks are available in many sizes and configurations, and can be portable, permanently installed or radiator mounted. Global Power Supply can help determine which type of load bank is best for your power system requirements and which meets applicable electrical codes for your area.

Load Bank Testing of CAT Olympian Diesel Generator

Portable Load Bank Test


For more information about Global Power Supply's load banks, contact our critical power experts today.
Additionally, check out our blog post, “Nine Reasons Why Load Banks are Essential to your Critical Infrastructure”.