I just picked up a small FF for the front of my boat and am going to use a trolling motor mount. I've read that it's hit or miss whether there will be electrical interference on the FF. I have one 12V battery for TM/lights/accessories, separate from my starting battery, and I ran the wire to the ow for it using #6 wire when I rewired the boat. There's a Blue Sea power post mounted under the bow and that's how I attached the power leads for the TM. It would be very easy to attach the power for the FF to that but I'm wondering aha is the likelihood that I'll get electrical interference? There appears to be some kind of balun on the power wire, but I don't know how effective it will be for suppressing interference. My option is to run a wire to the rear of the boat and hook the new FF to the starting motor. I'm not a fan of having anything else connected to the battery you depend on to get home, but I don't think a small FF is going to draw enough current to kill a deep cycle battery. What do you guys think about this? I'm sure there are a lot of people running a TM and FF off the same battery.

You can try it, won't hurt nothing; however, most boats are rigged to run electronics off the start battery.

Odds of RFI Electrical Noise increases when using the power supply from the same as Trolling Motor Battery. Yo uwill never know until you put in the water and test it .

I have tried to do it that way on a couple of different boats and got interference from the trolling motor on both. I think you would probably save yourself some time if you just ran another wire from your starting battery to your fish finder.

That may be the path of fewer problems. 20' of #18 marine wire isn't that expensive. Since I'm already going to be up under the console, I may as well reattach the power to my console FF to the starting battery also.

If you're going to be running the wires anyway, do yourself a favor and run #14AWG --- much less resistance in that size and you won't lose as much voltage to the units.

Just MHO!

C.

+1 absolutely.

I agree. According to a wire selection calculation, estimating the total length of the wire run, #14 will give less than a 1% voltage drop. I don't know why Lowrance would make a blanket statement to use #18 wire to extend the wiring not knowing how long the run is going to be.