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[url "javascript: addTag(':/')"][unsure][/url][#005028]Hey there tubeN2, With reference to charging a 12 volt 7amp battery, can you over charge the battery or will it stop charging once the battery meets it's peak? I have a basic Class 2 charger. I have a battery tester however, one of its range is 9 volts and the next is 15 volts. Testing at 9 volts shows a full charge whereas testing at 15 volts has the needle just in the green zone.[/#005028]
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Most class ll transformers don't have the means of restricting the current flow therefore you could overcharge your battery at some point or cause other damage. The battery will generally heat up and could leak or explode if overcharged or charged to rapidly.
As far as the meter goes, the 9volt setting is insufficient for a 12v system. The 15volt setting will only show you that there is some charge but it is trying to detect at the 15v range and doesn't have the capacitance to raise the scale.
You can get smaller digital VOMs from some electronic places that have auto ranging capabilites. Even the auto parts stores have some small meters that could give you a better reading.
Let me know if this answers your question correctly or if you need more specifics.[url "javascript: addTag('cool')"][cool][/url]
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[url "javascript: addTag('cool')"][cool][/url][#0000ff]I think we need to clarify that there is a difference between a "battery tester" and a volt meter. Simple testers just tell you if your battery has any kind of charge. The volt meter tells you exactly how many volts your battery is putting out.[/#0000ff]
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[#0000ff]As we have discussed in previous threads, a 12 volt SLA battery can take a charge up to almost 14 volts. It then slowly drops in voltage as it powers your sonar...or whatever. Once it drops below 12 volts in output, the battery is on its way to running out of power. By the time it hits 11 volts, your battery is not capable of operating anything and is likely to suffer some damage if you run it dry...especially if you do not get it back on a charger soon and get it up to full charge.[/#0000ff]
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[#0000ff]SLA batteries are not "deep cycle", like the boating fraternity sets up in their craft. Those big batteries are designed to survive being drained before recharging. Gel cells are not. Run them too low, too often, and you will shorten their life.[/#0000ff]
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I've had smoked salmon, smoked chicken and smoked buffalo. When it comes to smoking a tester, I wouldn't know which end to light.[url "javascript: addTag('crazy')"][crazy][/url]
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There is nothing more frustrating than to see a trusty tester go up in smoke, spark or start to glow at an inappropriate time.[url "javascript: addTag('pirate')"][pirate][/url]
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I don't know if this is true for all SLA's but mine has neoprene pressure release valves. It's impossible to overcharge since the excess gas is released through the valves and it makes a high pitched whistling sound to alert you.
If you don't have them you can always use the "ear test". Hold your ear to the battery and listen for a fizzing sound. That means it is fully charged and over charging. If there is no way for the excess gas to escape you will get swelled spots on your battery case over time. The case may even crack, so be careful.
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