h enough to reveal any
improperly burned joints, short-circuited cells, or cells low in
capacity for any reason. The discharge tester is suitable for all
batteries used on cars and trucks.

For an Incoming Battery. Take a hydrometer reading of each cell. If
the readings are all below 1.200 and are within 50 points of each
other, most likely all the battery needs is a bench charge, with a
possible adjustment of the gravity of the electrolyte at the end of
the charge. The discharge test should in this case be made after the
battery has been fully charged.

If the gravity readings are all above 1.200, or if the reading of one
cell differs from the others by 50 points or more, make the discharge
test, as shown in Fig. 179.

After fifteen seconds, read the voltage of each cell. If the cells are
uniformly low in voltage; that is, below 1.5 volts per cell, the
battery needs recharging. If the voltage readings of the cells differ
by 0.1.0 volt or more and the battery is fairly well charged, there is
something wrong in the cell having the low reading, and the battery
should be opened and examined. With a discharged battery the
difference in cell voltage will be greater, depending on the extent of
the discharge, and only experience can guide in drawing correct
conclusions. A short-circuited cell will give a very low voltage
reading. Remember that the actual voltage reading is not as important
in indicating a defective cell as the difference between the voltage
readings of the cells. A cell which gives a voltage which is 0.1 volt
or more less than the others is generally defective.

For Outgoing New, Charged, or Repaired Batteries. Just before putting
the battery into service, make the test as a check on the internal
condition of the battery, particularly if the battery has been
repaired or has stood for sometime since being charged. (It is assumed
that the battery has been charged and the gravity of the electrolyte
properly adjusted when the test is made.)

The battery should not show more than 0.10 volt difference between any
two cells at the end of 15 seconds, and no cell should show a voltage
less than 1.75 volts, and the voltage should remain fairly constant
during the test. If every cell reads below 1.75 volts, the battery has
not been completely charged. If one cell is more than 0.10 volt lower
than the others, or if its voltage falls off rapidly, that cell still
needs repairs, or is insufficiently charged, or else th