re rapidly than the
sediment would accumulate due to normal wear.

Heavy usage on a battery will also cause considerable sediment in the
bottom of the cells, so that it is necessary to investigate carefully
whether it is overcharging or overwork. A few questions as to method
of operation and load requirements will aid in deciding the cause of
excessive sediment. (See When and How to Charge, page 468.)

Sediment Space Filled.

When the space below the plates is filled up with sediment and
touching the plates, the cell becomes short-circuited and will
deteriorate very rapidly. It will be noticed, however, that the
sediment is heaped in the middle of the cell. If the cells are
unbolted and unshaken, it will level the sediment and leave a space
between the sediment and plates. It is very important that the
sediment be shaken down before the cell becomes short-circuited. This
will very often prolong the life of the battery a number of months.
When the sediment space is completely filled, approximately all the
active material will be out of the positive plates.

A thorough study should be made as to the general condition of the
battery and method of operation before forming an opinion or
suggesting any change in method of operation.

Check Ampere-Hour Meters

On plants which have ampere-hour meters, the meter should be checked
as to its speed on discharge, and also check position of the meter
hand at the time of inspection, to see if it checks with the specific
gravity and the pilot balls. (See Ampere Hour Meter, page 467.)

It will generally be found that when a battery is sulphated, it is
operating in very low specific gravity, or, in other words, the
charges have not been carried far enough to drive all the acid out of
the plates.

A battery that is not receiving quite enough charge may not as a whole
become "sulphated," but several cells might become considerably weaker
than the others and become "sulphated," causing trouble in these
particular cells. Such cells will not bubble freely, or possibly not
at all, when the other cells are bubbling freely. Therefore, a few
questions to the user will generally help in locating the low cells.

Cells that are in trouble, or which soon will be, can very easily be
picked out by making a few tests on the battery. Therefore, on all
inspections, regardless of the age of a battery, it is suggested that
the following tests be made: Take a specific gravity reading of al