Voltage drop

[osprey877]

All the voltage drop articles and tables etc. that i have read assume a single gauge of wire for the entire run. This may be a dumb question, but what Is the effect of mixing different gauges? For example if table says to use 12awg for a 20 Ft. Run, can I use 6" of 14awg at one end if the rest of the run is 10 awg?? if my new bilge pump comes with 18 gauge wire and its mounted 20 Ft from my battery, do I not need to worry so long as I keep the run of light gauge wire short and use 12 gauge for the rest of the run??

[donradcliffe]

The short answer is yes. The marine industry is notorious for using wire that is too small on their various gadgets. You will be fine as long as you use the correct wire size for most of the run.

[Stu Jackson]

You do the calculations for each section of different sized wire.

[dfelsent]

Originally Posted by Stu Jackson

You do the calculations for each section of different sized wire.

Do not forget that the fuse or breaker must be sized for the smallest wire you use.

10 feet of #2 followed by one foot of #14 will have much lower drop than 11 feet of #14, but no higher current carrying capacity.

[osprey877]

OK, thanks all. I think I have it figured out now.