Fluid conductivity sensor for actuating and testing an electroexploding device

Disclosed is an apparatus for sensing the electrical conductivity of fluid wherein when electrodes of the apparatus are exposed to fluid. When the electrodes are exposed to a fluid with a predetermined salinity, a voltage is developed on a capacitor which in turn fires a load, such as a resistive bridge wire. Also disclosed is a testing circuit, whereby the integrity of the circuit can be ascertained without the necessity of actually firing the circuit.