Load Bank Testing for Generators: What & Why?

If you have a generator, you need to make sure that it runs efficiently. This is important if you want the generator to continue running for as long as possible and more importantly, be reliable. However, most generators are rarely used. They sit in a corner waiting for that one downtime event.
Now, that’s a problem. When a generator is left unused, it can end up falling victim to other faults. Sometimes, these faults may go unnoticed by a no-load test.

That’s where load bank testing comes in.

What is Load Bank Testing?

Load bank testing is part of the typical preventative generator maintenance plan, which needs to be carried out on an annual basis. This method of testing ensures that your generator stays in shape and is available when you need it the most.

More importantly, it’s to make sure that your generator is capable of handling the highest load possible.

How is it Carried Out?

Load bank testing assesses all the major components of a generator in order to determine whether or not they’re still functional. The equipment used in these tests deliver artificial loads to the generator by making the engine operate at certain temperatures and pressure levels.

This kind of testing is very important for emergency generators that are rarely used and remain unexposed to heavy loads. In fact, the standard rule is to go in for load bank testing if your generator has never handled loads higher than 30% of its standard kW rating.

The process of load bank testing involves activating a prime power or standby generator and letting it run at maximum capacity with an artificial load for a fixed period of time. During this, data that offers a better understanding of the generator’s status is collected.

A successful load bank test is one that can verify that your generator is capable of handling large loads for long hours.

Here is a basic list of all the steps involved in load bank testing:

• Starting up and running the generator until the temperature of the water becomes stable.
• Transferring all of the automatic and manual transfer switches to the emergency source.
• Using the load bank to step load the generator until the intended load is achieved.
• Taking out the load bank load once the test is completed. This is the first thing to be done after such tests.
• Transferring all the transfer switches back to the standard position.
• Letting the generator cool down.

In our next blog, we’ll be taking a look at all the equipment used in load bank testing.