[caption id="attachment_4212" align="alignright" width="150"] UPS engineer Mark Trafford[/caption] It was another early start today time waits for no UPS engineer! With all the equipment and tools ready, we travelled up to Manchester where we were to test a 75kVA generator on load as part of a generator maintenance programme. During a generator test it is essential to check that the generator will be able to cope with the load it is designed to support, just in case of the unlikely event of a power cut. When planning generator maintenance, we acknowledge the possibility of a power cut even if our clients dont! We checked the status of the automatic mains fail (AMF) panel first, as, obviously when we are testing the generator, it means that it wont work in the event of an outage an ironic situation that we prefer to avoid! A typical generator maintenance test takes at least three hours so we do not want to leave a customer without energy for that amount of time while we complete the testing! We carried out the following generator maintenance pre-test checks: coolant; oil; electrical/mechanical; and battery. We then simulated a power cut to test the generator, incrementally increasing the energy load (starting at around 10%) and recording the voltage thereafter at regular intervals. The oil pressure and coolant temperature was also recorded. We eventually increased the load to 66kW (or 110%) for about 45 minutes, and then allowed the generator to cool down very gradually. After three hours of testing I was glad I had my ear defenders with me the noise was deafening! The data we collected today as part of the generator maintenance programme will later be sent to the customer electronically to keep him up to date with the safety and efficiency of their UPS unit.