.The Allen-Bradley 1760-L20BBB-EXND is a compact controller which belongs to the 1760 family of Pico controllers. Pico controllers are user-friendly and economical controllers designed for simple applications including building, automation, and plant control. The 1760-L20BBB-EXND is designed for 24 Volts DC input power. An acceptable range of input voltages is from 20.4 to 28.8 Volts DC. The current drawn by the controller is 140 mA. The power dissipated during operation is typically 3.5 W. The 1760-L20BBB-EXND has twelve 24 Volts DC digital inputs out of which 4 inputs can be used as analog inputs. It also has 8 MOSFET outputs which are rated for 24 Volts DC (20.4 to 28.8 Volts DC range). The I/O capacity can be increased by connecting available expansion modules to the Pico controller. Four of the inputs on the 1760-L20BBB-EXND can be used as high-speed counters. The maximum shielded cable length supported for these inputs is 20 meters.

A real-time clock is integrated into the 1760-L20BBB-EXND while the controller does not include a display or keypad. The 1760-L20BBB-EXND features an LED indicator on the front of the device. The LED indicator displays input power status and RUN / STOP status. To prevent injury or equipment damage, installation of the 1760-L20BBB-EXND should be performed by trained personnel. Further safety requirements, applicable regulations, standards, and codes should be followed where relevant. The dimensions of the 1760-L20BBB-EXND are 110 x 107.5 x 58 millimeters and it weighs 300 grams. The working temperature range is from -25 to 55 degrees Celsius at 5 to 95% relative humidity.