wsm wg972-e4 Workshop Manual page 46

WG972-E4, WSM
Checking Battery Specific Gravity
CAUTION
• If battery acid (dilute sulfuric acid) gets on you it could
cause blindness or burns, or could cause corrosion of
machinery and tools so please be careful when handling.
• Wear safety glasses and rubber gloves when performing
battery maintenance and inspection (measuring specific
gravity, filling water, or charging).
• If the gas that is generated is ignited by an ignition source,
it may explode so be very careful with sparks and fire.
• Keep your body and face as far away from the battery as
you can when performing maintenance and inspection.
• Do not allow people who do not know how to handle a
battery or who do not sufficiently understand the danger
perform inspection or maintenance.
(Measurement items)
 Zero adjustment
1. Open the cover and drip water on the prism surface using the
included rod.
2. Close the cover.
3. Aim in a direction that is bright, look into the lens, and adjust the
focus until the gradations can be seen clearly.
4. If the boundary line is not on the gradation baseline (0 position),
turn the adjustment screw until it matches.
5. When zero adjustment is complete, wipe the prism and cover
surface with a soft cloth or tissue paper.
 Measurement of test fluid
1. Open the cover and drip test fluid on the prism surface using the
included rod.
2. Close the cover.
3. Aim in a direction that is bright, look into the lens and read the
gradation of the blue boundary line.
4. When the measurement is complete, wipe the prism and cover
surface with a soft cloth or tissue paper.
(Reference)
Electrolyte specific gravity and amount of discharge.
Use the following table as a reference.
(A) Electrolyte Specific Gravity
(B) Discharge
NOTE
Temperature conversion of electrolyte specific gravity
• Battery electrolyte specific gravity changes based on
temperature.
• Insert the value identified on a specific gravity meter into
the following conversion
correction to learn an accurate specific gravity value.
(Standard temperature assumed to be 20 °C (68 °F))
D = Dt + 0.0007 (t - 20)
20
D = specific gravity
20
temperature of 20 °C (68 °F)
D = measured specific gravity value at the electrolyte
t
temperature t °C
G-20
GENERAL
(C) Good
(D) Charging is necessary.
equation for temperature
value converted to
9Y1211108GEG0033US0
standard
KiSC issued 07, 2015 A