BatteryMinder 1500 vs Schumacher 2/12/75 charger

[esox07]

OK, I have a BatteryMinder 1500 (1500ma) with desulfator. I have a deep cycle trolling motor battery that until now, I just used the BatteryMinder 1500 on between uses. However, I am taking the canoe and trolling motor camping in a couple days and play to use it several days in a row which will require fully charging between uses. My question is: If I drain the battery down to 1/2 or 1/4 capacity one day, will the BatteryMinder 1500 enable me to charge it over night to a full charge for the next morning...Lets say 12-16 hours? Or, would I be better off bringing the Schumacher 1275a - 2/12/75 and use that overnight? I am thinking I will need the 12 amps of the Schumacher to get it fully charged over night but would rather just be able to use the BatteryMinder 1500 if that would suffice.
The battery is a 105 AH battery if that matters.

Second follow on question, should I ALWAYS use the Schumacher between uses to bring the charge back up quickly or is it OK to just put the BatteryMinder on it and let it take it's time topping off the battery?

Thanks for any advice,
Bruce

 

[alldodge]

IMO, use the Schumacher always, and only use the Minder when it will sit for weeks or more without use

 

[km1125]

OK, so the BatteryMinder will charge a bit over 1A... with a 105AH battery drained about 50%, that's about 50AH... so it would take the BatteryMinder AT LEAST 50 hours to recharge it. Realistically, the last 1/4 charge or so takes as long as the first 3/4, so it would really be more like 70 hours to get the battery completely full.

You should use the Schumacher to get the bulk charge done, so I'd run the Schumacher about 4 hours (at the 12A setting, which would be about 48AH), then put the BatteryMinder on and leave it overnight.

The BatteryMinder has MUCH better regulation and will never overcharge the battery. I can't say the same thing about the Schumacher!!

 

[esox07]

The schumacher claims it will never over charge and will shut off when the battery if full and kick back on when the charge drops. But, yah, that is kind of what I thought. I need to run the regular 12amp Schumacher to charge it up quick and the let the Batteryminder top it off for the most optimal charge. The Batteryminder has a desulfication function as well.

Thanks guys.

 

[km1125]

It's kinda funny... I have those very same chargers, but your Schumacher is probably newer than mine.

 

[esox07]

Oh, I think the Shumacher is probably 10 years old. I have another Schumacher that is older but that is on loan to a buddy right now.

On the Schumacher 1275a, have you ever had it where the charge level needle bounces wildly back and forth like the charger is turning on and off rapidly? Does that just mean it is fully charged?

 

[alldodge]

Oh, I think the Shumacher is probably 10 years old. I have another Schumacher that is older but that is on loan to a buddy right now.

On the Schumacher 1275a, have you ever had it where the charge level needle bounces wildly back and forth like the charger is turning on and off rapidly? Does that just mean it is fully charged?

Many charger manufactures list desulfication, but these chargers can only do so much, and IMO it isn't much. Either the battery has reached full charge for the setting its on, or something is wrong with the battery. The quote below is from Shumacher's FAQ's

What does it mean when the green LED blinks ON/OFF and the needle bounces? All automatic battery chargers in the automotive market today have some sort of voltage regulation to prevent overcharging the battery. The rate of the flashing is dependent on the battery type, its rated capacity, the degree of discharge, its age, the temperature, as well as the amperage rating of the battery charger.
If the charger's green LED begins blinking when you connect the charger clips to the battery, the amperage in-rush current to the battery is reaching the pre-set shut-off voltage and the charger is shutting down. The voltage will drop as soon as the charger shuts down, turning the charger back on. This may also mean the charger has detected a battery problem - for instance, its ability to take or hold a charge. Sometimes a battery may be sulfated (accumulation of lead sulfate on the battery plates), and the sulfation is creating a high resistance to the current flow (ability to accept a charge). Or, perhaps the battery is deeply discharged (below 8-volts).

If you have plenty of time, I would use the 2 amp setting and let it charge up slow, and don't bother with the maintenance charger until winter