Product Description

The X20DC1976 is one of B&R Automation's digital counter modules that incorporate an ABR incremental encoder. With its compact design and lightweight construction, it is the perfect tool for monitoring the output of digital devices. Aside from its ABR incremental encoder, the X20DC1976 offers two more non-analog inputs that work best for latch inputs. The standard voltages used by this digital counter module are 5 volts, 24 volts, and GND. It also uses a NetTime timestamp for facilitating counterchange during operation. Overall, the X20DC1976 is best for push-pull encoders without a complementary signal.

The digital inputs for the X20DC1976 employ an input filter with hardware response time of less than 2 microseconds. Both digital channels use 24 VDC but allow -15% to 20% input voltage. Approximately, the input current of each channel is 3.3 mA when the terminal voltage is allowed to reach its nominal value. The channels employ 3 wires for connections and have the following switching thresholds: 5 volts DC (low threshold) and 15 volts DC (high threshold). These threshold voltages dictate at which values of the input will the module start to consider it to have changed to another state. The low threshold sets the boundary of switching from high to low, while the high threshold sets the boundary of switching from low to high.

On the other hand, the X20DC1976's ABR encoder uses a 5V asymmetrical supply with a maximum input frequency of 250 kHz. Normally, the ABR incremental encoder employs 4x evaluation and draws 300 mA from the supply. In case of short-circuit faults or overloading, the ABR incremental encoder will cease to function, assuming its protection devices work correctly.