Anybody having issues with minn Kota chargers ?

[riverrat29]

None really had two other boats that had them factory installed..Had a 3 bank in a Cobra that I had to replace out of warranty, but that is it. Just bought a boat couple years ago that had a older Noco Pro pack IV that finally went bad and needed something to go back. Dual Pro makes a 4 bank but its heavy & huge just will not fit in the bilge. The Noco Geniuis after some research had some issues too with AGM batteries and RF pulses stressing electronics during charge, so after much deliberation I went with MK.

[riverrat29]

So I fished this eve for a little while and some home and plugged in to see what would happen. After 20 minutes on the cranking battery was at 75% On the led and it was throwing 15.8v to it and you could hear it bubbling pretty good. The trolling batts were at 50% led at 14.4-14.7v not bubbling. I would have left it but I wanted to go inside and don't trust it. I would think the bank 4 should have gone to float mode considering it was chraged and the motor kept it up and I didn't run anything but my two hds units while i was out. I can't figure why it would be throwing the coals to that battery so much making it bubble/boil loud enough to hear it

[Larry3215]

So I fished this eve for a little while and some home and plugged in to see what would happen. After 20 minutes on the cranking battery was at 75% On the led and it was throwing 15.8v to it and you could hear it bubbling pretty good. The trolling batts were at 50% led at 14.4-14.7v not bubbling. I would have left it but I wanted to go inside and don't trust it. I would think the bank 4 should have gone to float mode considering it was chraged and the motor kept it up and I didn't run anything but my two hds units while i was out. I can't figure why it would be throwing the coals to that battery so much making it bubble/boil loud enough to hear it

Im confused. I thought you already figured out that this charger is busted/defective/bad/over charging/not working properly? Why are you still using it and what is there to figure out beyond "its not working correctly"? :)

[billnorman1]

Main sounds high.

[riverrat29]

Im confused. I thought you already figured out that this charger is busted/defective/bad/over charging/not working properly? Why are you still using it and what is there to figure out beyond "its not working correctly"? :)

Sorry for the confusion, I didn't mention this earlier in the thread. Because I got conflicting information from two different MK reps on the phone about it, but they said swap it out anyway. They don't trouble shoot them at the factory when returned, but it seems nobody you talk to can give a direct answer about how the blasted thing is actually supposed to work. Do I think what is happening normal? Heck no, I have owned boats my whole life and never seen a charger do what this one is doing. I didn't have much time to fish but wanted to see what it would do with partially discharged batteries. I asked to speak to someone more tech savoy to explain to me what is supposed to be happening at that point in the charge cycle.

[Larry3215]

I was mostly teasing you :)

You can find out what the charger is supposed to be doing by looking up the charge profile for the type of battery you have. All chargers should be following pretty close to the same profile when they are set to the same type of battery. Wet cell vrs AGM vrs Gel, etc. The battery guys tell the charger guys what profile is "supposed" to be used - not the other way around.

The charger guys sometimes add or do different things during the maintenance mode such as desulfating, or they may shut off completely for periods of time instead of continuously trickle charging, but the basic profiles should all be the same. Of course, charge times will vary depending on the charger power rating.

[riverrat29]

It's all good. I was doing some reading and found some basic charging profiles for wet cell batteries and yes you are correct. They coincide with the 14.4-14.8VDC max output per bank that one person at MK referenced. That would equate to roughly 2.32-2.46V per cell during charge and 2.0-2.3V during float/maintenance. Charger has to be suspect here. New broken (expensive) stuff is really frustrating. I like to be an educated buyer but I dang sure don't want to have to be an expert in that arena to solidify what is going on with someone's product. In the end we all want our stuff to work and just go fishing. This board is a family of really smart and talented people though and I enjoy bouncing things like this out there when they come up.

[Lou r Pitcher]

Yes, MinnKota PC series seem to utilize a basic 3 stage charging algorithm (BULK, ABSORPTION, MAINTENANCE ) Those voltages are below 15 volts.

However the PC series chargers include an equalization feature utilizing high plate cleaning voltages that are said by MinnKota to be applied each time the unit is AC powered.

A 'deep equalization' for flooded lead acid batteries is also stated to available which is recommended by MinnKota to be manually initiated once per year, or every 30 charging cycles.

15.8 volts or so is a typical voltage for a brief battery equalization.

Your phone line support person does not seem to be aware of the PC series' deep equalization feature.

Your charger boiling away the electrolyte as you described seems may be applying and remaining longer than normal (or is stuck) in this 'deep equalization' feature. If so, until a replacement charger is provided, you may be able to utilize the charger in the AGM mode without having the equalization voltages being applied boiling your electrolyte away.

[riverrat29]

Thanks Lou ! I hope my replacement will be here tomorrow and I will test it out and see how it does.

[riverrat29]

Spoke to a "higher up" tech guy at MK today. Real nice fella. Gave him the details of what this device was doing during the charge cycle and he stated the only time that 15.4-15.9V is applied to a flooded battery is in deep equalization mode which is a manually manipulated event. If the batteries are charged already and the unit is plugged back in, it will re-start the charge cycle but quickly go to float/maint mode. What this charger is doing is not normal and he was very interested at getting this one back to run some tests. He has never heard of one of these new PC series units do this.

[Lou r Pitcher]

There seems to be deep equalization which is manually initiated at those higher voltages. The tech literature also mentions a routine equalization performed once, each time the charger is powered up....its voltage may be less than deep equalizations with less intensive boiling.

The concern for performing repeated charging cycles is largely with AGMs which have no way to release the repeated equalization's electrolyte boiling inducing pressures other than permanent losses of electrolyte through the operation of the battery's release valve.

So less of concern cycling a charger on/off to flooded lead acids as the equalization;s increasing losses of boiled electrolyte can be easily replaced with increased volumes of distilled water.