Minuteman E24 - 12.3 Hydrometer Testing Batteries

12.3 Hydrometer Testing Batteries
12.3 Hydrometer Testing on Lead Acid Wet Batteries
• Hydrometer testing can used to measure the specific gravity of deep cycle
batteries. This allows you to detect weak cells, which are causing loss of
running time. It can only detect these types problems. The hydrometer
should have specific gravity markings such as 1.265, 1.250, 1.225, and so
on.
• Hydrometers with the four balls are not accurate enough for this
test and are not recommended.
• Fully charged batteries should read 1.265 and will decrease as batteries
are discharged until they reach 1.120. This test should be done when
batteries are charged and cooled. Allow one hour or more to cool. It can
also be done after batteries are partially discharged, if they are allowed to
cool. However, you will not be able to detect the full capacity of the
battery.
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