Temperature compensation

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Under temperature compensation , a measure is understood to be an undesirable temperature effect counteracts with the aim that a change in temperature does not result in a device to a change in the behavior or injury.

For example, the undesired dependence of an electrical resistance on the temperature is compensated for by the additional use of a resistance with an opposite temperature dependence. A copper wire increases its resistance with increasing temperature; a thermistor reduces it. By connecting them in series , the influences partially cancel each other out. An adaptation of the influences for the most complete possible compensation , however, requires additional circuit complexity.

A strain gauge (DMS) changes its electrical resistance not only when its elongation changes, but also when its temperature changes. To measure a strain, the influence of temperature is essentially compensated by a differential circuit in the form of a Wheatstone bridge , with a further strain gauge - in the simplest case unstretched - being used in addition to the stretched strain gauge. If both strain gauges are exposed to the same temperature, the same temperature influence is eliminated when the difference is formed.

A Bourdon tube is the centerpiece of a pressure measuring device , which deforms elastically under pressure. Since the elastic property is temperature dependent, the pressure display must be compensated. This is e.g. B. possible with a bimetal strip that changes the transfer of the elastic deflection of the spring to a pointer so that the display is largely only pressure-dependent, but not temperature-dependent.

Intelligent chargers adapt the charging currents to the temperature of the accumulators and thereby compensate for the various operating conditions in order to optimize durability.

See also