The precision of the bimetallic thermometer

Bimetallic thermometer working principle is to use two different temperature expansion coefficient of metal, in order to improve the temperature measuring sensitivity, is usually made of metal spiral coil shape, when multi-layer metal temperature change, the layers of metal expansion or contraction, makes the spiral coil rolled up or let go. You know about the precision of the bimetallic thermometer today.

temperature compensation scope is a typical range smaller than working temperature range, within the scope of the bimetallic thermometer work will certainly achieve its performance index. Temperature affects the output from the two aspects, one is zero drift, 2 it is to affect the full scale output. Such as a full range of + / - X % / ℃ and + / - reading X % / ℃, in the full range of + / - beyond the temperature range X %, within the scope of temperature compensation + / - reading X %, if it were not for the parameter, will lead to uncertainty in use.

transmitter output to the degree of change is caused by pressure changes, or caused by the temperature change. Temperature influence is to understand how to use the transmitter complex, as part of the bimetallic thermometer decided how much precision accuracy has nonlinearity, hysteresis, repeatability, temperature, zero offset calibration, the influence of the temperature.

the temperature range of pressure transmitter transmitter usually a transducer calibration period indeed two temperature, one of the temperature period is normal working temperature, the other is a temperature compensation scope, the normal operating temperature range is refers to the transmitter in the working status not be destroyed when the temperature range, while beyond the scope of temperature compensation may not reach its application performance metrics.