Johnson Outdoors MinnKota MK 315D On-Board Battery Charger (3 Banks, 5 Amps per Bank)

This 3 bank charger has been a joy!! Have 3 batteries and charge all at one time. Do not need my portable battery charger

Easy to install and work great.

I have this installed in my 1996 19 foot Ranger flats boat. I have a 24 volt trolling motor, so I use all three banks. Two banks connect to the two 12 volt batteries used for my trolling motor, and one bank connects to the battery that starts my 2011 Mercury 115 Pro SX Outboard Motor and also runs my GPS, Humminbird Sonar, and other electronics. If you have not hooked up a charger before to a 24 volt system like this, let me just say that you hook the batteries up just like there were two batteries sitting there. The potential between the positive and negative terminals of each battery is still 12 volts even through the positive of one battery is wired to the negative of the other battery to create 24 volts between the positive terminal on one battery and the negative terminal on the other battery.I have a 125 volt receptacle in my boat like this  Marinco 150BBI Marine On-Board Charger Inlet (15-Amp, 125-Volt, Black) . So as to avoid cutting any wires on my charger which would void the warranty, I simply wired another receptacle to the back of the Marinco receptacle. The charger stays plugged in all the time to this receptacle. This way, I can just plug my extension cord into the Marinco receptacle without opening any hatches. It works very well.By the way, Minn Kota or another manufacturer should make an adapter like this. Some people are not going to wire in their own receptacle even though it is easy to do. It would be good to advertise such an adapter as an accessory to this charger because many people would want a setup like this.The charger has lights which show yellow when charging, flashing green when in trickle charge mode, and solid green when the battery is fully charged. Each bank has its own light. If there is a malfunction or the bank is not working, the light is red. I rarely look at the lights because I would have to lift up my seat to see inside where the charger is mounted. However, sometimes I want to see that my batteries are being charged so I have a look.Generally on return from fishing, I just plug in the extension cord and forget about it. It easily recharges my batteries overnight. I can leave it plugged in for weeks at a time. I always have power for my trolling motor and for cranking my Mercury Outboard motor. I love being able to do this, and thanks to this Minn Kota charger, I can do this.** [WARRANTY ISSUE] **I bought this item in June of 2011 from Amazon. About a year and a half later, one of the banks showed a red LED and was not charging my battery. I noticed that the inline fuse on the positive cable from the charger was blown, so I replaced the fuse. As soon as I did, the new fuse blew. I called Minn Kota technical support and explained my situation. Although he did not say so, it seemed to me that he had heard of this situation before. The tech quickly shipped me out an entirely new charger and provided a prepaid return label for me to return the defective unit. I could not be happier with this kind of technical support. I'm not sure why this kind of device would fail in this way, but from reading other reviews, apparently they do frequently. I run in saltwater all the time, but the unit is completely sealed and quite frankly, after a year and a half it still looked brand new like when it came out of the box. If this unit were to last three years with this kind of warranty protection, I am a happy fisherman. Of course, I would prefer for it to last longer, but I don't know of any other chargers that would have a longer warranty.If this item were to fail when out of warranty, I would quickly go buy this unit again. The only thing that would change my mind was if another unit priced similarly received reviews by people claiming that their chargers seemed to last forever.So I absolutely love this product and I highly recommend this item for charging up to three batteries on a saltwater boat.

Was lookin to add another one of these to a boat i purchased recently an noticed i bought my first one 7 years ago figured id leave a long term review.When i picked this up i had two 27 group size batteries in series for 24 volt for my trolling motor and a single 12v cranking battery. I noticed other chargers were either for 12v or 24v not both this one does both and detects that automatically. These things are literally plug all you have to do is mount it. This unit is large it was bigger than i thought it would be and it is heavy but its very well made and i found room for it in my 17ft bass boat, you can mount thise sideways upside down it doesnt matter.In 7 years this charger has been through alot used year round plugged up from November untill april or may. Through spring summmer and fall it sees alot of use as i fish quite often. It has never overcharged a battery through the winter it keeps my batteries maintained so they withstsnd the cold and i dont have to replace them. I purchased 3 new batteries when i bought thus unit i still use 2 of them.As to construction this thing has been splashed slightly submerged once or twice and sits in the dampest part of my boat amid fuel fumes and other equipment and never once has it let me down. That is why when i was lookin to add another one to my new boat i looked at minn kota first. I grew up in a 12ft jon boat with the first power drive trolling motor and the first digital fish finder both made by humminbird/minn kota. They were a leader in innovation then and they still are in my book. Ive used the other brands an they have all failed at which they were replaced with humminbird/ minn kota products.

Was shipped fast and was what I was expecting no issues 👍

Installing on the inside of my center console was a bit of a task by myself, you have to have the holes drilled exactly correct or you will screw yourself, had to have someone help me hold wrench from outside so I could get the bolts tightened, once installed I love it and works great

So far, it's amazingly easy and simple. 2 times recharging and my batteries have never performed better. I have around 6 year old batteries set up for 24 bolt and they have been ridden hard but taken care of. This is probably going to buy me another 2 years of life out of them and so simple to use.3 bank = (1) 12 volt main starting battery, (2) 12 volt on a 24 system.Just hook a lead to each battery and leave the 24 volt jumper on. As long as there's no load on the 24, like your trolling motor running while you're trying to charge then it works amazing. 3 batteries = 3 banks. 2 batteries = 2 banks......

I just spent 400.00 on a starting battery and two trolling motor batteries for my bass boat. When I would come home from fishing I would drag out my battery charger and charge my batteries up one at a time. Well that gets old! A friend recommended an on board battery charger/ maintainer. This keeps the batteries at a full charge and maintains them so when I go fishing all I do is unplug the extention cord and go! I have a MinnKota trolling motor and it has always performed well so I thought I would get this MinnKota charger. It constantly monitors the battery condition and it will alert you of anything wrong with batteries or a short, etc. This is a three bank charger so it is perfect for my three batteries. Mounts up real nice and this unit seems well built also. Hookup wires are fused and are pretty long if you want to mount it a little further from your batteries. A very good investment in my opinion! Would for sure recommend it!