The measuring current leads to a temporary charging of the measuring resistance (122) with a measuring power which is higher than the nominal power of the measuring resistance (122).

In addition, a second measuring resistor (29) is provided.

The measuring resistance (1.1) is connected to the electric cable by means of stress-relieved measuring resistance connection wires (1.2) and internal conductors (4).

The divider resistance (3) is made in a single piece with a measurement resistance (10) and is provided with taps (4 to 9).

The measuring resistance (1) and the internal conductors (4) are arranged in a metallic protective tube (8), which narrows (8.1) in the vicinity of the measuring resistance (1).

The measuring resistance (2) is embodied in the form of a strip.

The measuring resistor 8 is formed in a U-shape or a C-shape.

The characteristic curve of the measurement resistor preferably conforms to DIN-IEC 751.

At least one measuring resistor (Rm) is arranged in the third current stream.

The heating resistor (Rh) and the measuring resistor (Rt) are fitted together on a wafer during production and tuning.

Means (SS, PS) are also provided to record the change in resistance resulting from the switching in of the measurement resistor (Rm) and to signal any change in resistance that deviates from a set value.

Additionally, the bridge has a non deformation-sensitive resistor (F) which is connected in series to the deformation-sensitive measuring resistor (C) in the bridge resistor.

The fibrous material of at least one layer is at least partially electroconductive and is embodied as an electric measuring electrode and/or measuring resistor.

Both transistors (27, 28) and the second measuring resistor (29) are connected in series.

Current measuring is made independent from the offset voltage of the operational amplifier by including the precision resistor in an additional voltage divider.