| Author |
 Topic  |
|
|
pinzpilot
New Member
USA
1 Posts |
 Posted - Dec 16 2007 : 11:36:34 PM
|
New here so hope this is the correct forum for my questions.
I just bought a 24v BatteryMinder 1/2/4amp charger. The purpose: to maintain the 24v system for my military vehicle(2-12v Optima Red Tops connected in series). I thought I understood the tech staff and the manual to indicate that the two batteries must be separated and "qualified" individually before connecting them for maintenance charging. Both 12v batteries indicated weak or sulphated with one battery indicating 12.3v and the other 12.2v. So, I connected the first 12v battery to the 24v charger and it charged for approx 6-8hrs and then was rejected for maintenance mode. I repeated this procedure again, same results. I then connected the other 12v battery to the 24v charger and repeated the exact same procedure for it as I did the other battery. Exact same results. After 12+hrs of rest, I tested each battery with a digital voltmeter. One read 12.6v, the other 12.4v
I then decided to connect the batteries back in series and charge them that way. 24v charger first indicated good condition, but after about 5 minutes, it indicated weak or sulphated and then immediately went into float mode. Manual says to keep it this way for a minimum of 72hrs. After 3hrs, I used the digital voltmeter to check the charging voltage. Uhhh, something doesn't seem right. One battery indicates 14.2v and the other is 12.8v Something's wrong isn't it??? Have I damaged these expensive Optimas by charging them with a 24v charger? When they are connected, why is one reading 12.8v and the other 14.2v??? Until I can get an understanding of all this, I've just disconnected everything. Can anyone please help me with this. Thanks.
Electronically Challenged,
Mark |
|
|
Aaron Cake
Administrator
Canada
6718 Posts |
Posted - Dec 18 2007 : 09:29:59 AM
|
Does the charger automatically switch to an appropriate charge voltage for a 12V battery?
You can charge a 12V battery at 24V, but this is only useful for fast charging the battery. You need to monitor the heating of the cells to assure you aren't charging too fast. Certainly, you can not leave a battery like this unattended and for a long period of time.
If a battery has sulphated, there is nothing that can be done to fix it.
If these Optimas were purchased within the last 5 years or so, they are junk anyway. The quality of Optima has gone down the toilet after the company was sold to Jonhson Controls. |
 |
|
|
shah80
New Member
Pakistan
1 Posts |
Posted - May 06 2008 : 07:14:43 AM
|
| i need gel or dry battery charger circut fully automatic |
SHAH |
|
|
| |
Topic |
|
|
|
24v Charger to 12v Battery?
