# Understanding current, wire size, and voltage drop

I am trying to understand the relationship between these. I have 24AWG 300V copper PVC insulated wire. From what I have learned, this wire can be used to connect a Panel LED that draws <20 mA @ 110V to a 110V main power terminal strip.

I have read that voltage drop would be a problem with increasing lengths of wire at smaller gauges. This wire's length is less than 2 feet and at room temperature. Using a calculator, the Vdrop is on the order of a thousandths of a volt. Am I doing my math correctly? I have only been able to find examples of this situation where people used 14 gauge wire, which has to be way overkill.

• 14 awg might be overkill, but if you're talking about something installed by an electrician it might just be what they have lying around, because 14 awg is commonly used for 10 A circuits (in the US). A couple of feet of 14 awg is something that would be lying around as scrap during any electrical installation work. Mar 6, 2014 at 19:03
• @ThePhoton: Actually, that would be 15A circuits in the US. AWG12 is normally used for 20A circuits. Mar 6, 2014 at 19:10
• @DaveTweed, Yes you're right. Brain freeze. Anyway I think Spehro got the right answer: You need to pick the wire gage according to how it's fused. Mar 6, 2014 at 19:51