Your backup generator is a lifeline for your business. It will allow you to keep operating even when weather conditions or mechanical failures threaten to stop you. While a lot of the maintenance should be left to the professionals, there are some things that any facility manger should be aware of. Knowing a little bit about basic generator issues and the testing options that are available will pay off when you need your backup power system to work for you.
Transfer Switch Testing
The transfer switch is the equipment that turns your generator on. Most transfer switches are designed to monitor the traditional power supply (normally your local power utility). When your traditional power supply goes out or drops off significantly, your transfer switch will pass power providing responsibility to your generator. If this switch is not working, you will lose power even with a working generator. This can be a problem because you may not have staff members on hand who know how to manually transfer responsibility over to your generator. Each generator is a little different so make sure that your maintenance provider teaches someone on site how to perform the test. In essence you will be electronically switching power from your utility to your generator. This confirms that your transfer switch is working. This test should be performed monthly. If you have heard that performing this test monthly will put unnecessary strain on your system, do not believe it. Your system is designed for this and it’s better to be safe than sorry.
Load Bank Testing
Load bank testing is an actual test that you will need to have done. Basically, this test requires your generator to start up and perform at full capacity. Most often your generator will not use its entire capacity. A load bank test uses outside equipment that simulates what would happen if your generator had to crank up and perform at its highest level. The test will verify that your generator can operate for a specific amount of time and that it will be able to turn off and on while handling a full load. If your generator is not able to perform to its design standards, you will need to have a professional look at your system. Whether or not your system needs to operate at its highest level is insignificant. If your system is unable this is a sign of trouble.
Unloaded testing means that you test to make sure your generator can work at levels lower than its fullest capacity. This test is performed more often because it requires less equipment. It also does not ensure that your generator can handle full capacity. One other issue is that if your generator runs off of diesel, sometimes unspent fuel will end up in the exhaust of the generator. Your generator’s engine cannot work effectively without exhaust (think about the old banana in the tail pipe joke for car). This is called wet stacking and can hurt your equipment. Consequently, a load bank test generally works your generator hard enough to remove any unspent fuel left from unloaded testing. While this form of test will give you piece of mind that your generator can crank up, we do not recommend that yu make it the only means of testing your equipment.
Testing your backup power system is only one part of generator maintenance. It is an important part because it allows you to identify problems while you still have time to fix them.
If you are interested in learning more about generator maintenance, or need maintenance performed, we can help.