Hey Guys:

I'm replacing an HDS 12 graph on my bow with a Carbon 16 and I'm adding an AT module that will reside in the compartment on the starboard side.

The bow graph has the original power supply that came with the boat and I've purchased Ancor 10awg marine grade wire to run from my 125ah lithium battery to power both the Carbon 16 and the AT, which I will run separate power to both from the supplying battery.

I'm not an electrician, but I do understand smaller diameter wire + longer runs creates a drop in voltage to your end source. I'm trying to rectify this by using a quality 10awg wire, but at some point you must connect it to the very small diameter Lowrance power cable to interface with the graph. My logical thinking says that doesn't make sense.

Would it not be appropriate to cut as much of the supplied Lowrance power cable off and only require a couple of feet for the voltage to travel vs. coiling up the extra 20' and forcing the voltage to run thru the roughly 15' of 10awg to then connect to the small diameter Lowrance power cable and run some total of 20' of coiled wire before reaching the graph? I would also ask this question about the AT module as well.

Yep, they use a tiny cheesy 18g wire, (maybe smaller) and then it’s our job to make it work properly. I cut off as much of the factory wire as possible, but even then you have to find a decent way to connect 10g to their junk wire.

Thank you for the reply that confirms my logic....I'm glad to hear what appears to be a ridiculous oversight by Lowrance is recognized by someone other than myself.

So I will definitely heat shrink the connection, but do I spend the time soldering or just use a step down butt connector and maybe fill some of the void by stripping more of the small Lowrance wire and doubling it or tripling on to itself before crimping.

They say not to solder on boats or airplanes due to the vibration and the heat weakens the wire, causing a breakage in the wiring. But, I’ve soldered mine due to the size difference and haven’t had any issues yet. Just make sure you stick a fuse on your 10g near the battery, if you end up cutting off the lowrance fuse holder.

Excellent advice...thank you.