Abstract: This invention relates to an overfill prevention system for preventing the overfilling of tanks when filling up large tanks from a fuel distribution truck. The system operates by monitoring and automatically controlling the filling process by use of a power take off switch assembly that is connected electronically to a secondary overfill prevention system that is also connected to a signal probe located in the tank that is being filled. In operation, once fuel contacts the signal probe, a communicator signal is sent from the signal probe to a secondary overfill prevention system, which interrupts a looping electrical current through a fuel shut off sensor assembly to a power take off switch assembly along a connecting cable.

Abstract: This invention relates to an overfill prevention system for preventing the overfilling of tanks when filling up large tanks from a fuel distribution truck. The system operates by monitoring and automatically controlling the filling process by use of a power take off switch assembly that is connected electronically to a secondary overfill prevention system that is also connected to a signal probe located in the tank that is being filled. In operation, once fuel contacts the signal probe, a communicator signal is sent from the signal probe to a secondary overfill prevention system, which interrupts a looping electrical current through a fuel shut off sensor assembly to a power take off switch assembly along a connecting cable.