Abstract: A resistor heater includes an anode (10) arranged along one side and a cathode (20) arranged along the other side of a thin-line-shaped resistor (30). The anode (10) is connected to the resistor (30) at connections points (P2, P3) by a plurality of branches (13, 14) arranged at a certain interval along the resistor (30). The cathode (20) is connected to the resistor (30) at connection points (P1, P4) by branches (23, 24) arranged at a certain interval along the resistor (30). The connection points (P1, P4) are located at positions shifted from one another along the resistor (30). A portion (31) of the resistor (30) located between the connections points (P1, P2) and a portion (32) of the resistor (30) located between the connection points (P3, P4) function as effective regions of the resistor (30).

Abstract: In many cases, the influence of temperature on the quality of a coil has a disturbing effect. Therefore, a coil inductance is produced such that the influence of temperature on the quality of the coil is substantially compensated for in a particular range of the system frequency. To this end, a second coil having a second quality value Q2 is magnetically coupled in series to a first coil having a first quality value Q1. Moreover, the two coils are selected in such a way that for a particular range of the system frequency f, the quality value Q1 decreases as the temperature T increases and the quality value Q2 increases as the temperature T increases. A coil conductor for the first coil made of litz wire and a coil conductor for the second coil made of solid wire may be used to create such a temperature dependence.

Abstract: To compensate for the temperature dependence of a resonant circuit, it is known to use an a.c. current source, with which the resonant circuit is excited in dependence upon the ohmic resistance of the coil conductor material. The task of compensating for temperature may to be solved without a costly closed-loop control process and with few losses. A magnetically coupled second coil is connected in parallel with the first coil to be compensated, and an NTC thermistor is connected in series with one of the two coils so that the series connection is connected in parallel with the other of the two coils. The NTC thermistor is selected so that, in conjunction with the two variable sized ohmic resistors of the two coils, the circuit arrangement has a specified total ohmic resistance, which is substantially independent of temperature.

Abstract: An iron wire resistor connected in shunt with the current limiting contacts of a circuit breaker. The current limiting contacts are in series with the main contacts of the breaker, and are separated by extremely high fault currents before the main contacts can respond. Opening of the limiting contacts shunts the high fault current through the resistor. The resistor has a positive temperature coefficient of resistance and heats rapidly to sharply reduce the magnitude of the high fault current.To prevent the connection between the resistor and a low resistance copper conductor from being destroyed by the high fault current an intermediate resistance value terminal of copper clad stainless steel is employed between the resistor and the copper conductor.