Breaker Sizing

[Ron20324]

Just want to be sure I completely understand. Are you saying that you... step "down" to a #14 from there.

As MIT says, the larger wire is strickly used to lessen the voltage drop, not to accomodate a larger amp draw. BUT the breaker at the panel has to be rated for the smallest wire in the entire circuit. An option would be to put a 30-ish breaker in the panel, then put smaller fuses where the wire "steps down" to the smaller gauge.

On my B323 there were 3 wires from the breaker panel to the mast. I need to free up some breakers, so used the larger wire of the three on just one breaker then put three switches and 3 5-amp fuses in the access panel in the salon under the mast step. The switches located there allow me to see the lights as I test or turn them on.

 

[Stu Jackson]

Ron's right. Based on a earlier post, though, I do not use anything smaller than 12 ga. on my boat. Why? 'Cuz the boat builder used 14 ga. for the lighting circuits and it su*ks. My motto: "bigger is better" when it comes to wiring (within reason, guys and girls).

 

[mitiempo]

I stick to the 15 amp (typical) breaker in the panel and do not install fuses at the mast base.

14 awg is ok depending on length of run. 27' length (there and back) is 3% drop with 5 amps and 14 awg. Longer should be 12 or larger.

 

[jfmid]

Crimper question for MS

Hello Maine,

Little question about the FTZ crimper. It arrived today and the question is the smallest wire size listed on the little chart is 6 guage wire. It shows the die settings for that. I need to crimp #8 wire. Should I just use the same dies as for #6?????

Thanks again,

John

 

[mitiempo]

I have the same crimper. If you use the die for #6 it will not be a very tight crimp.

My solution is to avoid #8 wire.

I'm interested in Maine's reply as well.

 

[jfmid]

Did a test crimp using the die for #6 on #8 wire and #8 connector ring and couldn't pull it apart with vise grips on the wire and ring. Pulled with all I got and it stayed. Then tried to twist and see if I could loosen it and it stayed. Guessing it's ok.

 

[mitiempo]

That sounds ok. I find the crimp quality varies a bit depending on the brand of lugs used. Some are better than others with the listed dies and some need another setting for a proper crimp.

 

[Maine Sail]

I have the same crimper. If you use the die for #6 it will not be a very tight crimp.

My solution is to avoid #8 wire.

I'm interested in Maine's reply as well.

Even though I have crimp tools for 8 GA I avoid #8 and just jump to #6... #8 is tough to get lugs for and to find the wire in-stock on a regular basis..

Please be aware that their are TWO lug sizing plates on the crimp tool. On the right handle is the sizing for "flared starter lugs" these are the cheaper, thinner lighter weight lugs like those sold by Ancor. On the left side is the lug sizing for heavy duty lugs. DO NOT mix these up!!!

Crimping a flared starter lug on the heavy duty lug setting will result in a poorly executed crimp..