The EL2124 digital output terminal connects the binary 5 V DC control signals from the automation device on to the actuators at the process level with electrical isolation. The EtherCAT Terminal contains four channels whose signal state is indicated by LEDs.

Special features:

• 5 V DC outputs
• Connection of different load types possible (ohmic, lamp load)
• Max. output current 0.02 A per channel
• Overload and short-circuit proof push-pull outputs

https://www.beckhoff.com/vi-vn/products/i-o/ethercat-terminals/el2xxx-digital-output/el2124.html