The Essex Engineering Model 2415 Manual Loading Station is a conservatively designed, reliable unit that provides a 4 to 20mA DC output which is directly proportional to a voltage or current input.  When in the AUTOMATIC mode, the output is directly proportional to the input, and the digital display will indicate the AUTO input signal.  While in the AUTOMATIC mode, when the READ button is depressed, the digital display will then indicate the MANUAL value.  By manipulating the SET potentiometer the MANUAL value can be made to equal the previously noted AUTO input signal, thereby providing a "bumpless" transfer.

Conversely, when in MANUAL mode, the digital display indicates the manual set point.  By depressing the READ button, the digital display will show the AUTO input signal.  By releasing the button and adjusting the SET potentiometer, the MANUAL signal can be made to equal the previously noted AUTO signal.  Therefore, when going from or to AUTO or MANUAL operation, bumpless transfer can be achieved.