Testing circuit.

摘要

A testing circuit is provided for testing the operability both of a load (30) and of a capacitor (26) incorporated into a main detonator circuit and arranged to discharge into the load for detonation thereof. A test pulse is generated at a central controller to which a ring of detonators is connected on a harness. The test pulse is routed via the harness for storage in the capacitor. A controlled switch (44) is operated to allow the capacitor to discharge into the load. A transistor (52) is operated by the discharge signal, the transistor having an output for delivering a discharge value signal (56) in response to the discharge signal remaining above or falling below a threshold value. The discharge value signal is latched and is in turn used to inhibit a local oscillator (66). The inhibited signal from the oscillator is routed back to the controller so as to indicate a fault either in the capacitor (26) or in the load (30). <IMAGE>