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WHAT IS A VOLT METER

A simple volt meter is a hand held device used to measure Volts, Amps, Resistance.  This style volt meter has a rotating selection wheel that allows you to select which type of function you want to form.  There are two types of voltage and current.  The first kind is called "direct current" AKA "DC".  The 2nd kind is called "Alternating Current" AKA "AC".   The symbols on your volt meter typically show a straight set of lines for "DC" and squiggly set of lines for "AC". 

The fancy type of volt meters are "Auto Ranging" which means that they automatically adjust back and forth from small voltages in the 0.2 range, and big voltages in 1,000 volt range.  The cheaper volt meters require you to do this by using the selector wheel as shown in the photo. 

You will need to take special care to always turn off the volt meter when you are done.  The 9 Volt battery inside will go dead within a day if you leave it on!  If the battery goes dead, there are two screws on the back.  Use a small screw driver to remove them and replace the battery. 

Note there are DC generators and AC generators.  This pedal power bike generator is DC.

1. Insert the black voltage probe connection into the bottom hole on your volt meter labeled "COM"

2. Insert the read voltage probe cable end into the hole labeled "VΩmA"

3. When you are done, your cables should look like the meter in the picture.

4. If you are measuring a 12 Volt battery, rotate the volt meter selector switch to the DC voltage setting at the 20 range as shown.

5. Now insert probes into the voltage monitoring banana plug ports as shown.  You can order a set of banana plug patch cords that will stay fixed in the monitoring ports so that you don't have to hold the probes with your hands.

You will need to know how "full" you battery is after charging it or using it.  Some powerpacks have an indicator on them that shows you how full the battery is.  If you don't have one of these indicators, then you will need to calculate the state of charge of your battery using the following steps.

1. Make sure you battery is not being used to power anything up.  If it is connected to any kind of electrical components like inverter, TV, laptop, cell phone charger, radio, etc.  disconnect those items. 

2. Let your battery settle for at least 15 minutes.  A lead acid battery can give you a much lower than normal voltage reading during or just after it was used to provide power to something.  Likewise, it can give you you a higher than normal volt reading during and just after charging.

3. Insert the black voltage probe connection into the bottom hole on your volt meter labeled "COM"

4. Insert the read voltage probe cable end into the hole labeled "VΩmA"

5. If you are measuring a 12 Volt battery, rotate the volt meter selector switch to the DC voltage setting at the 20 range as shown.  If you are measuring a 24V Battery setup then select the "200" range.

6. Use the table to determine the stat of charge of your battery if it is a sealed absorbed glass mat style A.K.A "AGM" battery.  This is the type of battery allowed to ship through the mail system and is most commonly in power packs.  If you have a flooded lead acid battery or a gel cell battery the voltage ranges will be a little different.

STATE OF CHARGE LOOK UP TABLE FOR SEALED ABSORBED GLASS MAT BATTERY (A.K.A.  AGM)