Electricians may replace items such as circuit breakers, fuses, switches, electrical and electronic components, or wire. When working with complex electronic devices, they may work with engineers, engineering technicians, or industrial machinery repairers. Maintenance work varies greatly, depending on where the electrician is employed. Electricians who specialize in residential work may rewire a home and replace an old fuse box with a new circuit breaker to accommodate additional appliances. Those who work in large factories may repair motors, transformers, generators, and electronic controllers on machine tools and industrial robots.
Electrician helpers begin to learn the trade informally by working for experienced electricians.
While learning to install conduit, connect wires, and test circuits, helpers are also taught safety practices. Many helpers supplement this training with trade school or correspondence courses. Electrical inspectors examine the installation of electrical systems and equipment to ensure they function properly and comply with electrical codes and standards. They visit work sites to inspect new and existing sound and security systems, wiring, lighting, motors, and generating equipment. They also inspect the installation of the electrical wiring for heating and air-conditioning systems, appliances, and other components.