The state s energy crisis and associated rotating outages have increased interest in emergency, backup generators for providing electricity during power outages. But those generators can pose a safety concern to SMUD field crews who work on SMUD s power lines every day and can cause severe damage if not installed correctly.
Electricity traveling in reverse is called back feeding .
The danger from back feeding electricity arises because the transformers that convert high voltage electricity into lower voltage will work in reverse. If a generator is back feeding 120 volts into SMUD s system, a nearby transformer could convert that to 12,000 volts, posing a serious risk to SMUD employees who may believe that the lines are de-energized. A generator can be used to produce electricity in two ways. The needed electrical equipment or appliances can be plugged into a generator with an approved extension cord, or the generator can be tied to the home s electrical system with an automatic or manual transfer switch. The purpose of the transfer switch is to eliminate back feeding by ensuring that the home or business has been disconnected from the SMUD distribution system before the generator is used to produce electricity.