CHAPTER 7 ■ NINE-VOLT BATTERIES
Interpreting Test Results
If the multimeter display shows a negative number (see Figure 7-6), then something has gotten reversed.
Check that the test leads are connected to their proper terminals on the battery and on the meter. Switch the
probes if necessary. Don’t worry if you got a negative number, that doesn’t hurt the meter at all.
Figure 7-5. Probe tips touching battery terminals
Figure 7-6. A negative number indicates a mixed-up connection
If the display shows zero, some connection isn’t making full contact. Make sure the leads are fully
inserted into the meter terminals. Make sure the metal tips are touching the metal portion of the battery
terminals.
If the meter displays a positive number (see Figure 7-7), then you’re measuring the battery correctly.
Depending on the type of battery and the capacity remaining, a valid voltage of a 9 V battery should be
between 5 and 10 volts.