Should a UPS module be load tested every year? The real question is why do this type of testing and what are its benefits, versus the risks of not doing this type of testing.
Whether you test an UPS module every year really depends on a couple of different factors. The top concern is can your facility's critical load be taken off line or placed onto a generator backup in order to have this type of testing performed? If your UPS system does not have load related problems then the test will only confirm that the module will be able to handle full load. Is this knowledge worth the cost of doing a load test?
Another item to consider is, where will the load banks be staged? What type of heat will be generated and how will that the added heat effect your facility? When doing large system tests there will be a large amount of heat generated and that can effect sprinkler systems if the load banks are staged inside of the building. Are doors going to have load bank cables ran through them so that the doors can not be locked or used for normal use, this may require extra security personnel during testing? These are all questions that should be address prior to scheduling a load test.
When customers are looking at a significant load increase on system, they can have load bank testing performed prior to increasing the critical load that will be applied to the system. This is one of the best examples of when to perform load bank testing. With this type of testing, customers can have a higher level of confidence in the system before the increased critical load is applied and if there are any problems noted then they can be corrected prior to the adding of additional load.
In addition, on some older systems it can make perfect sense to do a system test with load banks in order to re-calibrate the system and the modules. On some of these older systems that use calibration potentiometers, these potentiometers can drift out of calibration over the years and by performing a recalibration it will insure that the system is operating at peak performance.