Trolling Motor fuse size

[Musky hunter 82]

So I just purchased a new Minn Kota Edge bow mount, it's a 12V 40 pound thrust model. My question is what size fuse should I use?

Thandk for your feed back, If others are wondering the samething with your motor post it here, maybe the smart guys out there can help us out.

[slammer]

I had a 30 amp on my last 12v setup. Got a 24v with a 60 amp now.

[BobT]

I have a Minn Kota Powerdrive 40P. According to my owner's manual it will use approximate 1A per pound of thrust at full power. I used a 40A circuit breaker when I first got it but at full power in a heavy wind it would trip the breaker if I was making a lot of steering adjustments because the extra current drawn by the steering motor would put it over the 40A threshold of the circuit breaker. I went up to a 50A and have had no more issues.

My owner's manual does not indicate using any fuse or circuit breaker in the electrical connections. I searched Minn Kota's HSOforum and haven't found any information about this. I'm beginning to suspect the motor's may be internally protected but that's only a hunch.

Incidentally for you 24v enthusiasts, according to my manual the same motor wired for 24v operation will use .75A per pound of thrust at full power. This means that the 24v motor uses a higher Amp-Hour than the 12v and therefore will be a heavier drain on batteries.

A 12v 40P motor will draw 1A x 40# = 40A at full power therefore one can calculate that (2) 105 Amp-Hour batteries connected in parallel for 12v will give you approximately 210 / 40 = 5.75 hours of running time give or take.

The same 40P motor connected to (2) 105 Amp-Hour batteries connected in series for 24v will draw .75 x 40# = 30A at full power and will give you approximately 105 / 30 = 3.5 hours of running time give or take.

This seems to suggest that the 40P motor is more efficient at 12v than it is as 24v. This is actually a surprise as I was expecting they would work out to be about the same or perhaps the 24v would have the edge but the facts tell a different story.

[rmb]

the 12v vs 24v vs 36v has been beaten to death. unfortuately most everybody wants to discuss the motor and not the batteries themselves. Peukert's Law is really the driving factor in this discussion but it is the least known/discussed factor and has a significant impact. all three common voltage motors have similar effeciencies but how the batteries themselves react is very different between the 3 in high amp draw situations. if you truly want to calc and compare run times between 12v, 24v and 36v you have to normalize the battery draw/performance using Peukerts's Law. Someday if we have batteries that do not follow this law then you can simply run out a simple calc of amp draw at a proposed load and compare back to amp/hours available in the battery/batteries chosen.

unfortunately that battery technology doesn't exist yet. This phenomenon is why the higher thrust rated motors are 24v and 36v. Could you make a 12v motor with these same thrusts absolutely but they would be less effecient in comparison due to the limitation of battery technolgy and how Peurkerts law dictates amp hour effeciency.

the minkota amp draw chart is very general at best. to assume that run time vs amp draw is linear is highly theoretical based upon a perfect battery that doesn't exist. well it may somewhere but not to joe public.

[LightningBG]

So I just purchased a new Minn Kota Edge bow mount, it's a 12V 40 pound thrust model. My question is what size fuse should I use?

Thandk for your feed back, If others are wondering the samething with your motor post it here, maybe the smart guys out there can help us out.

What gauge wire is it using? How long is the wire?

[Musky hunter 82]

Lightning, right now I'm using 10 gauge wire, that is about 12' long. Should I have a larger gauge wire for this size motor? Or will the 10 gauge be Ok?

[Tator2k]

Previous post. Minnkota recommends 6 gauge for TM installs. I've melt 8 gauge before with a 12v Powerdrive V2.

[Musky hunter 82]

6 gauge this really makes me wonder, is there a difference between marine wire and regular stranded electrical wire? The reason I ask is that I was using 8 gauge (non marine)stranded electrical wire before and when you look at the diameter of it compared to the wire that is connected to the trolling motor it was way larger.

[Deershooter]

I belive the marine wire is fine stand and can handle a higher current. The diference in size could just be a difference in the thickness of the insulation of the wire.

[Musky hunter 82]

When I checked the diameter of the trolling motor wire it's self (no insulation) it was a little smaller than the 10 gauge stranded wire that I'm using. It didn't look like the individual strands were smaller either, I really don't want to have to rewire the boat but if there is a big difference that I just might have to do that. I don't want the wire to melt on me.

[Deershooter]

10 gauge does seem a little small to me. I know in the eletrical industry it is usually use for 30 amp amplications. I am just not sure how that crosses over to low voltage dc. I would imagine that it would have the same rating. If it was me I would upgrade t the 6 gauge wire instead of taking the chance with the 10 gauge wire. It will be more work now but it could save you more work and fishing time later.

[BobT]

The rated current capacity of the wire has to do with the type of wire being used(single cond., cable, insulation type, etc.), the temperature rating of the insulation, highest ambient temperature the wire will be exposed to, and how the wire is installed (in raceway, free air, etc.)

I personally would not use the common types of 10ga wire found at your local auto parts or box store for a 40-50 amp load. You're inviting potential trouble. I think I would stay with at least 6ga to be sure.

Wire gauge is related to the cross sectional area of the wire, not the insulation.

[LightningBG]

30 amps is about the max 10ga wire should be handling.