Abstract: An safety control system especially useful for controlling the irrigation of crops. The system includes a transmitter having an extended range over two miles. A repeat cycle timer provides a repetitive time delayed input signal to the transmitter which transmits a signal while an irrigation system is operational. A receiver for receives the signal from the transmitter, and a time delay relay latches upon receipt of the signal by the receiver to close a circuit and provide power to a pump unit for a fixed amount of time. If the time delay relay times out without receiving a signal from the transmitter, the irrigation pump unit is shut off.