BK-300 is a emergency station device for manual operation of a control elements in case of a controller failure. The BK-300 can also be used as Manual / Automatic transfer station with or without bumpless characteristics, where the act of transfer does not generate disturbances in the process under control. BK-300 station can operate in automatic mode, the analog input value is faithfully repeated on the analog output being transparent to the process. When in manual mode, the operator controls the process via a potentiometer on the machine’s front panel. BK-300 station is equipped with a digital input failure “Fail” destined to failure warning connection controllers and PLCs. When BK-300 station is in automatic mode and the fault signal is actuated, the analog output goes to the safety value and acts digital output that can be used to alert signal.