A simple battery checker

[FunGas]

Following a discussion about internal resistance, I find myself checking my batteries quite often, thus, made up a simple checker.
It's nothing more than a digital Voltmeter, an old Ammeter, momentary switch and terminal posts.
off.jpgon.jpg
The bulb is rated at 12V 50W, but I suppose I could parallel two for a harsher test.
I also found engaging the switch several times before taking a final reading puts more strain on the battery, giving a better reading.

[Sunking]

Following a discussion about internal resistance, I find myself checking my batteries quite often, thus, made up a simple checker.
It's nothing more than a digital Voltmeter, an old Ammeter, momentary switch and terminal posts.
[ATTACH=CONFIG]5512[/ATTACH][ATTACH=CONFIG]5513[/ATTACH]
The bulb is rated at 12V 50W, but I suppose I could parallel two for a harsher test.
I also found engaging the switch several times before taking a final reading puts more strain on the battery, giving a better reading.

Give you a tip I learned from a drunk RC pilot. Get an old blow dryer, take it apart and rewire it to use as a load on for your batteries. They usually have 2 to 4 sections for different wattages. Use an ohmmeter to figure out the resistances. Some RC pilots use them to discharge their LiPo batteries.

[FunGas]

blow dryer

You mean the heater coils?


There are some low resistance wirewounds somewhere in the workshop, the 6" variety, failing that I have boxes of surplus, out of tolerance, carbons.
I've used model car / 12V drill motors with a huge fan before for draining batteries, works well, but they takes up a lot of workbench.

Come to think of it, there's a brand new 100W Peltier somewhere, doing nothing too. Time for some more experiments...

[Sunking]

Yes sorry the heater coils.