Current limiter resistor effective under fault condition - is flat for easy mounting in encapsulated electric operational components with intrinsic safety

The resistor is intended for encapsulated electric devices of intrinsic safety for limiting a current occurring in an emergency. It is flat and pref. arranged directly adjacent to a boundary surface of the device. The resistor is pref. in the form of a conductive track of a printed circuit, made of high-ohmic resistance material. The circuit board may form the boundary surface of the protected electric device. Resistors of this design and for this purpose may be deposited on a substrate, using thick-film technique. In this instance the substrate may form the boundary surface of the protected device. Alternately, they are formed by a thin-film technique. Resistors of this type are typically incorporated in a transmitter.