St. Joseph, Champaign County, IL | Oversizing of wire, hurts nothing but the pocketbook. Bigger wire more easily carries the load than the correct sized wire, but there are costs to the oversized wire. For one, larger wire costs more than the correct sized wire, if you're comparing the same type of wire in the different sizes. Oversized wire can mean needing larger conduit, which mens larger straps to install it. Both cost more than smaller conduit and straps. Finally, larger wire can also mean needing to use larger lugs, wire nuts, kearnies (split bolts), etc… to make connections with. All of these cost more money as they get larger in size.
My Introduction to Electricity class, at the University of Illinois, through the College of Ag (actually called ACES by then), taught us about wiring motors and how the wire is sized to the motor, not the breaker in this case. The breaker is also sized to the motor, based on the inrush current. Dare I say that it's the Engineering part, where sometimes the practicality doesn't come through, that let you down? Engineering would say that a 2" water hose would more efficiently carry the water to water my garden. It's generally not practical to try and use a 2" hose for that application though. |
How big of wire do I need?
