The EL3602-0020 analog input terminal handles signals in the ranges ±10 V, ±5 V, ±2.5 V and ±1.25 V. The voltage is digitised to a resolution of 24 bits, and is transmitted, electrically isolated, to the higher-level automation device. The input channels of the EtherCAT Terminal have differential inputs and possess a common, internal ground potential. The signal state of the EtherCAT Terminal is indicated by light emitting diodes.

The desired calibration certificate can be downloaded from here using the respective serial number.

https://www.beckhoff.com/vi-vn/products/i-o/ethercat-terminals/el3xxx-analog-input/el3602-0020.html