In Part 1 of this article, we explained that a service panel is an electrical box which accepts incoming power from a utility and distributes it to various circuits within a building. One of the places it could distribute power to would be to a sub-panel, which is a similar but smaller electrical distribution box. These are normally placed at some distance from the service panel, such as in a garage, barn or workshop, or in a mechanical room with several dedicated circuits for specific equipment.
The sub-panel is fed from the service panel, and will be turned off if the main breaker is switched off in the service panel. A typical set up is to have a 200-amp service panel in the home and a 60-amp sub-panel in the garage or workshop. This does not mean the electrical system has 260-amps of electrical capacity, it still has a total of only 200-amps.
The most common reason for installing a sub-panel is add new circuits without running individual wires for each new circuit over this distance. It would be time consuming, costly and you’d experience more voltage loss with a lot of smaller wires than you would with one large set of feeder wires going to the sub-panel. It also is more convenient to reset a tripped breaker in a nearby sub-panel than to go all the way to the service panel.
The sub-panel distributes power just like the service panel through individual circuit breakers. The breakers protect the circuits at their amperage value marked on each breaker, such as 15-, 20- and 30-amps. Notice in the image above that there are only a few breakers (1 per circuit) unlike the service panel which has many more breakers.
If you are adding an addition to your home, or adding more electrical tools in your workshop/garage, or have a barn that needs more circuits, consider adding a sub-panel to your system. It is the most convenient way to expand, and is often the least costly way also.
Contact us today and let us help with this. Adding a sub-panel can be dangerous and it should be done by a licensed electrician. For over 37 years, Frye Electric has been serving the Indianapolis area, and we’d like to serve you, too.