Ramkala Manufacturers Analog Glass Soil Thermometer, Certification : IMD

Thermometers

• General description :
  
  • For routine observations of air temperature, including maximum, minimum, wet-bulb and soil temperatures, liquid-in-glass thermometers are commonly used. Such thermometers make use of the differential expansion of a pure liquid with respect to its glass container to indicate the temperature. The stem is a tube having a fine bore attached to the main bulb:
  • The volume of liquid in the thermometer is such that the bulb is filled completely but the stem is only partially filled at all temperatures to be measured. The changes in volume of the liquid with respect to its container are indicated by changes in the length of liquid in the stem; by calibration with respect to a standard thermometer, a scale of temperature can be marked on the stem, or on a separate scale tightly attached to the stem.

Specifications : The thermometers shall be of liquid-in-glass, solid-stem type with enamel back as follows :

• Maximum thermometer - Mercury-in-glass, having a range from 35^oc to 55^oc
• Minimum thermometer - Alcohol-in-glass, having a range from -40^oc to +50^oc
• Ordinary thermometers (wet and dry bulb) - Mercury-in-glass, having from -35^oc to +55^oc

• Soil thermometers -
  
  • iMercury-in-glass having a range from +20^oc to +65^oc at depth of 5, 10 and 20 cm.
  • from -20^oc to +50^oc at depths of 50 and 100 cm.

The graduation intervals for all the thermometers should be 0.5^oc. The accuracy of ordinary thermometers, maximum thermometers and soil thermometers should be +0.2^oC and for minimum thermometers it sh ould be ±0.3^oc

The thermometers should be suitably mounted as per drawings given in IS:5681 — 1983. Each mounted thermometer with mount may be supplied in a wooden case with a hinged lid, of outer dimensions 400 x 110 x 65 mm. The thermometer with its mount shall be fixed to the box with two brass screws.