Technical Information

According to DIN EN 60751 it is necessary to publish the response sensitivity ( half-life tO,5) of sensor resistances and thermometers. The answer signal of the temperature sensor is noted on a temperature jump. The measurement takes place in the air flow of 1m/s and in flowing water of 0,4m/s.

These half-lives amount to in water for

• Glass - sensor resistances: between 0,14 and 0,8s
• Ceramic – sensor resistances: between 0,2 and 0,4s
• Sheath - sensor resistances: between 0,1 and 0,3s

These large spreads indicate that these values are strongly coupled to the design of the sensor resistance.

With a measurement insert, e.g. type according to DIN 43762, this half-life lies between 6 and 9 seconds.

With a thermo sensor with measurement insert and protection fitting, e.g. according to DIN 43772, between 36 and 40 seconds.

These changes and spreads depend on the following factors:

• The mass to be heated
• the heat transmission coefficients from material to material
• the heat conductor resistances of the materials
• the heat dissipation of the thermometer from the measuring bath (in longitudinal direction)
• the fit of the measurement insert in the protection fitting.