The Logic Module implements the logic "OR" or "AND" function in a variety of alarm or control applications. Often it is required that an alarm is activated by either of 2 or 3 seperate inputs. This is the "OR" connection. In other applications the alarm must be activated only when 2 or 3 seperate inputs are present simultaneously. This is the "AND" connection. This highly versatile module accepts either +12 volt signals or grounding signals. The inputs are completely isolated from each other. A simple wiring connection permits this 3 input device to function with only 2 inputs.