Technical specifications of direct-acting temperature regulators

Time constant characterizes the speed of the regulator's response to a change in temperature. It is measured in seconds and depends on the construction of the thermoelement and the method of sensor installation. The speed of the valve movement is higher in automatic regulators with low time constant values.

Proportional band of the regulator equals the temperature deviation from the set value at which the regulator valve will fully open or close. The value of the proportional band is different for different settings within the regulated range and is determined by nomograms provided in the technical description of the temperature regulator.

Hysteresis of the regulator equals the temperature deviation of the water from the set value at which the valve will begin to move to bring it to the desired value.

DN of the temperature regulator is the nominal diameter of the opening in the connecting pipes. The DN value is used to standardize the pipe fitting sizes. The actual diameter of the opening may differ slightly in either direction.

PN of the temperature regulator is the nominal pressure - the highest excess pressure of the working medium at a temperature of 20 °C, at which long-term and safe operation is ensured.

Kvs of the temperature regulator is the coefficient of flow capacity that corresponds to the water flow rate in m³/h at a temperature of 20 °C at which the pressure drop on the regulator valve will be 1 bar. The value of the flow capacity coefficient of the automatic temperature regulator is used in hydraulic calculations to determine pressure losses.