Lift pump command with logic gates

Circuit is divided in 3 parts. - On the left side is the electronic circuit. - On the middle is the control panel with from top to bottom : . The On/Off command circuit switch . Green LED : command circuit On indicator . Blue LED : automatic mode indicator . The inverter switch for automatic/override modes. . Red LED : override mode indicator . Yellow LED : pump running indicator . The pump motor circuit breaker . Red LED : alarm circuit breaker open - On the right side is the tank with from top to bottom : . A double pushbutton that is the "full tank" sensor (double for security) . A double pushbutton that is the "empty tank" sensor (double for security) . The pump motor supplied by a 24 V DC source. In automatic mode, the "full tank" sensor (full tank) starts the pump until the "empty tank" sensor (empty tank) stops it. In override mode, the pump runs continually excepted when "empty tank" sensor is activated. That's to prevent the pump from turning without liquid. Last updates : . added resistors between AND inputs and ground to ensure logical 0. . added power breaker and reorganization of the circuit in three parts with the control panel. . relay replaced by Darlington transistors. . sensors doubled for security. . motor supplied by 48 VDC . lamp replaced by motor supplied by 24 VDC. . added led indicator when breaker is open. . added FET to command Darlington.

published 10 years ago