Abstract: A relay for overcurrent or short-circuit protection is provided wherein the relay has a thermistor in the form of a film of polymer material. The thermistor is arranged over a large surface in the interior of the relay between a connection segment of a terminal element and a terminal plate coupled parallel thereto. By such design, the thermistor is serially connected into the load circuit of the relay. Upon the appearance of either an overcurrent or a short circuit, the thermistor makes an immediate shift to a high resistance value, thereby interrupting the load circuit.

Abstract: A circuit arrangement for driving a group of relays includes a voltage regulator for supplying a normal holding voltage and for supplying a briefly increased pick-up voltage upon connection of each additional relay. An ammeter recognizes the increase in current as the result of the connection of each additional relay and generates a control signal to the voltage regulator for increasing the voltage. Simple and effective control of the relays without high heat loss is thus achieved without requiring individual sensor lines and the like.

Abstract: A circuit arrangement for driving at least one electromagnetic relay provides that all of the excitation circuits can be connected to a constant voltage source in parallel relative to each other and jointly in series with the switching path of an electronic switch (FET). The electronic switch (FET) is switched through and blocked in impulsive manner whereby the pulse-duty factor is adjusted in a control unit depending on the operating voltage (U.sub.B) and the ambient temperature of the relay so that it does not fall below the minimum holding current required for the connected relays.

Abstract: In a relay, power lead elements of the load circuit are conducted between a core and a yoke in order to improve the response behavior of the relay as an auxiliary excitation. The power lead element is a stranded conductor having one end connected to the appertaining terminal element and the other end directly connected to the contact element. Therebetween, a stranded conductor is conducted from one side of the coil to the other through a transverse bore in a coil member flange. In this way, the stranded conductor and, thus, and the load circuit is well insulated from the winding and, moreover, the power lead element requires no space in the actual winding space, simplifying the assembly thereof as a result.

Abstract: In a coil for an electromagnetic relay, a delayed response is achieved by a short-circuit tube which carries the coil member and replaces a plastic tube which is otherwise used. The short-circuit tube is extrusion coated at its ends with the coil flanges so and a thin insulating layer is provided on the short-circuit tube under the winding in the region between the flanges. The dimensions of the winding and the core are not increased while a considerable delayed response for the relay is provided.