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Why cant I use a 12V charger on the MEP's?

kloppk

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The batteries are connected in series so one lead of the charger needs to go to one battery and the other lead of the charger needs to go to the other battery.
The positive lead of one of the batteries should be going to the starter. Connect the + lead of the charger to that battery's + terminal. Next connect the chargers - lead to the - post of the other battery.
 

Triple Jim

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Exactly how it is connected to the two 12v batteries? Maybe a photo would help.

Does the charger have a switch for 12v and 24v, or is supposed to sense this and automatically charge at the correct voltage?

Could your batteries be so discharged that their voltage is close to 12v, so the charger thinks it's a 12v battery?

Edit: I hadn't noticed kloppk's post when I typed mine. His description of the battery connections is a good one.
 

2hot6ft2

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Got my 24V charger today, it has tiny clamps but managed to get it onto the terminals of the battery on the oil filler side, the unit stays in 12v mode and will not activate 24v ;( Bad unit or do I need to hook it up differently somehow?
You need to hook it up differently.
It's easier from the other side where the starter is.
There you connect to the + terminal and IF you connect to the - terminal you will only get 12v like this
IMG_20161016_081344262.jpgIMG_20161016_081353528.jpg

But if you connect the - clamp to either the - (lower) connection on the NATO plug like this
IMG_20161016_081434289.jpgIMG_20161016_081440508.jpg
Or the - clamp on the negative connection where it connects to the engine like this
IMG_20161016_081547877.jpg
You will get the 24v to activate like this
IMG_20161016_081427442.jpg

The reason is with just the 1 battery between the clamps is just 12v. But this makes it show both batteries between the clamps.
Hope that helps.

P.S. I ended up keeping the charger. It was operator error that was making me think it was defective.
 
Last edited:

tennmogger

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I'm just guessing, like others are doing, but my take on this is that the batteries are dead and only showing around 12v total, in series. That automatic charger is thinking the battery (total) is 12v so it stays in 12v mode. Perhaps the batteries have to show close to 24v to make the charger start in 24v?

Maybe hook to one battery at a time to get charging going. The charger will think one battery is 12v and charge it, then do the other battery. Now they should read close enough to 24v that the automatic voltage selection will choose 24v when you hook up across both in series. You do not have to do any unhooking of the heavy primary wiring to do that individual charging.
 

JRM

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You need to hook it up differently.
It's easier from the other side where the starter is.
There you connect to the + terminal and IF you connect to the - terminal you will only get 12v like this
View attachment 649206View attachment 649207

But if you connect the - clamp to either the - (lower) connection on the NATO plug like this
View attachment 649209View attachment 649210
Or the - clamp on the negative connection where it connects to the engine like this
View attachment 649211
You will get the 24v to activate like this
View attachment 649208

The reason is with just the 1 battery between the clamps is just 12v. But this makes it show both batteries between the clamps.
Hope that helps.

P.S. I ended up keeping the charger. It was operator error that was making me think it was defective.

Thanks everyone, yup I just put it on one battery like a car (long day at work and wasn't even thinking) I haven't figured out my charger either, what's the red * and blue * mean above the voltage (bottom pict)? Like you I put it on my known low ATV battery and it went right up to green- The instructions are minimal at best.
 

2hot6ft2

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Grant, AL
Thanks everyone, yup I just put it on one battery like a car (long day at work and wasn't even thinking) I haven't figured out my charger either, what's the red * and blue * mean above the voltage (bottom pict)? Like you I put it on my known low ATV battery and it went right up to green- The instructions are minimal at best.
The red is for 3amp (red asterisk *) and standard batteries. The purple 5 pointed star (blue) is for 6amp AND AGM batteries like the Optima batteries.

The manual if you can call it that is not very good and when it does mention the purple it has a little star (like the 5 pointed star on the charger) that looks more like an asterisk just to confuse matters more. A magnifying glass helps to be able to tell it's actually a star.

In my pics it is on 3amp since I just hooked it up to take the pics, if I was going to leave it hooked up I would push the mode button to change it to the purple for AGM batteries.
 
Last edited:

JRM

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awesome, thanks! Does it charge when the green light appears? My hummed for a few seconds then went quiet when the green light came on. I tried many batteries and a few are known low ones and it still worked its way up to green in under a minute.
 

2hot6ft2

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Grant, AL
You're welcome. I have yet to see a green light on mine. If the green light is the fully charged light then it's supposed to automatically change to a 1.5amp trickle charge.

Still wondering if mine is defective considering the number of batteries I have put it on and have yet to have the charge status indicator go above the second LED.
 

87Nassaublue

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Sharpsburg, Ga
My 016B's alternator didn't put out enough voltage to charge the batteries. I didn't want to tear it down to replace diodes, so I added two cheap Schaumacher automatic chargers to it. They switch from 6 amps full charge to trickle to maintain. I hard wired them in and plug them into the convenience outlet to power them when the unit is running. To maintain the batteries, I can simply connect the power to the wall outlet. I found a place in the bottom of the frame on both sides where they snap in like they were designed to go there. They were $10 each at the salvage store. Walmart sold them for $25 each. It cost me $20 and a hand full of ty raps and some electrical tape. They work very well.
 
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