Shrt:circuit projected supply to surgical equipment - is disconnected by differencing circuit coupled to transformer primary monitoring load coupled to transformer secondary

摘要

The HF surgical apparatus has power supply to surgical electrodes automatically cut off when these electrodes are short circuited. The normal load varies between 50 and 2000 ohms. The load (Rp) is coupled to the secondary of an output transformer (6) whose primary is connected to a resistance monitoring circuit (12-20). This circuit monitors the resistance of the load in the secondary circuit. It produces a turn-off signal for the HF generator (1) when the resistance drops below a given value. The monitor consists of a differencing circuit.