Multi-function electrical testing apparatus - has voltage indicator lights with acoustic warning circuit and phase indicator for three-phase systems

摘要

The electrical inspection includes at least one voltage indicator circuit using luminescent tubes and an acoustic warning circuit using a vibrating sheet. A th ird circuit enables the order of the phases in a 3-phase system to be identified. This circuit has a resistance in series with condenser. All three circuits are connected in parallel between two input terminals of the apparatus. A third, auxiliary terminal is connected to the common point between the resistance and the condenser, across a luminescent tube.