Dulas Solar VC150, Handbook

Page: 40 / 156

40
B: HOW TO MEASURE
1.
TEMPEARTURE
Temperature is measured with thermometers. There are many different types of
thermometers. The choice of thermometer should depend upon the degree of
accuracy, the reliability, the response rate, the temperature range required and
budget available.
1.1 Refrigerator and freezer temperature
Temperatures are usually measured in the refrigerator and freezer compartments of
photovoltaic refrigerators with low –cost, simple low precision bi-metal thermometers.
This type of thermometer is robust, stable and simple to read.
It is easy to check the accuracy of a bi-metal thermometer by removing it from the
freezer or refrigerator compartment and placing it alongside another thermometer for
several minutes at room temperature. If the thermometer gives the same reading;
then most likely they are reading correctly.
Thermometers used in the compartments of refrigerators frequently have red/and/or
green ranges marked on the scale, which indicates the correct temperature range at
which the compartments should be operating.
The procedure is to read the temperature directly from the scale, which should be
marked in degree Centigrade (
0
C).
REMEMBER: THE VACCINE COMPARTMENT OF A REFRIGERATOR SHOULD
ALWAYS BE BETWEEN 0
0
C AND 8
0
C.