Abstract: This invention relates to a voltage level detector having a string of series coupled light emitting elements, such as light emitting diodes or low voltage lamps, as indicating devices. The light emitting diodes are series coupled to a constant current source. Parallel to each of the light emitting diodes is the emitter-collector path of a transistor connected. The base electrodes of the transistors are connected to the point with the voltage level to be detected through base resistors. When a transistor is in its conductive state the parallel coupled light emitting diode is by-passed and when a transistor is blocked current is diverted through the parallel coupled light emitting diode which then becomes lit.