Dulas Solar VC150, Handbook

Page: 53 / 156

53
3.
Insert the hydrometer into the electrolyte in a cell of the battery, squeeze the
rubber bulb, and draw enough electrolyte into the hydrometer to make the
indicator float freely.
4. Record the specific gravity reading as indicated by the float and adjacent
scale.
5. Return the electrolyte to the small cell in the battery being careful not to spill it.
6.
Insert a thermometer (mercury in glass type) into the battery so that the bulb
of the thermometer is covered in electrolyte but not touching the battery
plates. Wait until the temperature shown has stabilized and record the
electrolyte temperature.
7. Using the table below, which shows the temperature correction to specific
gravity, record the correction value.
Temperature Correction to Specific
Gravity Readings (to 15
0
C)
Electrolyte Temperature
0
C Correction to specific Gravity
55 +0.028
50 +0.024
45 +0.021
40 +0.017
35 +0.014
30 +0.010
25 +0.007
20 +0.003
15 0.000
10 -0.003
5 -0.007
0 -0.010
TEMPERATURE CORRECTION TABLE
Example
For 30 degrees centigrade the correction is +. 010