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Analog Multimeter for dummy::: how to measure a Battery voltage??

37K views 6 replies 4 participants last post by  techjunkie 
#1 ·
Analog Multimeter for dummy::: how to measure a Battery voltage??

Hi guys.. finally I got an analog multimeter...

I got a digital one few weeks ago and I hated it so much!! numbers are constantly changing so I decided to go with analog multimeter..



now.. regardless digital/analog I want to know how to check voltage of my car battery...

which mode should I put?? DCV, ohm, ACV, BAT, DCA??

Since I am measuring a voltage it should be either DCV or ACV.. am I right??

if so which number should I see??

10, 250 or 500??

seriously need your advise.. :)

thanks in advance
 
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#2 ·
DCV stands for direct current voltage and acv stands for alternating current voltage. Cars use direct current and it's based on a 12 volt system. If you just want to check weather or not you have voltage at any given point, place it on 10 volts and the needle should max out. If you want to be specific about what voltage you have place it on 250, but its going to be kind of hard to precisely measure your voltage. That's where the digital meters are great.
 
#5 ·
Sometimes a load test of the battery is required. In most cases a digital voltmeter is very effective in diagnosing an alternator / battery problem. If you dont get about 14 volts with the car running the alternator is not charging the battery, simple enough. If the battery voltage is not about 12.6V with the car not running, the battery is weak or undercharged. Sometimes the battery voltage appears OK with the car off untill a load such as the headlights is applied. In those cases, a battery load test is good since the battery voltage versus time for the load applied can tell you % of life left in the battery.
 
#7 ·
Thats the problem. Battery load testing usually requires specialized test equipment and the manufacturers data on what voltage that battery is designed to deliver based on ampere hours removed (amps of load times the number of hours the load is applied) and the amp draw at the time voltage is measured. Not simple DIY stuff. :censor:
 
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