It is very nice to have a backup power generator for those occasions when there is a power outage. This is particularly so in South Africa, where the national power provider has proven to be so unreliable in the near past. However, there is an added danger of using computers with a backup generator, and great care should be taken when using computers or other delicate equipment. The voltage and frequency of the power produced by a generator depends on the engine speed, and the speed is controlled by a governor. Some governors are mechanical, some are electronic. The job of the governor is to keep the voltage and frequency constant as the load changes. However, there is no guarantee that the voltage will remain constant, and you should avoid using a computer with a standby generator if at all possible.