EL3172 – Introduction

EtherCAT Terminal, 2-channel analog input, multi-function, ±10 V, ±20 mA, 16-bit, differential, electrically isolated

The EL3172 analog input terminal complements the EL3174, thus making 2-channel and 4-channel universal input terminals available in the EL31xx family.
The EL3172 has two individually parameterizable inputs.

Signals in the ±10 V or ±25 mA range can be processed per channel, including unipolar 0 … 10 V or 0/4 … 20 mA. Each channel can be set to U or I mode by the controller via CoE. The input voltage or current is digitized with a 16-bit resolution and is transmitted, electrically isolated, to the higher-level automation device.

With a technical measuring range of ±107 % of the 10 V/20 mA nominal range and the 25 mA measuring range, the terminal also supports commissioning with sensor values within the limit range and evaluation in accordance with NAMUR NE43. Both differential inputs are electrically isolated from each other and from the fieldbus.

107 % extended range The EL3172 is pre-set to a 107 % measuring range, e.g. 0x7FFF corresponds to  +10.737 V in the 10 V interface or 21.47 mA in the 20 mA interface. The previously known legacy range can be reset via CoE access. Then 0x7FFF will correspond to the full scale value again (FSV, e.g. 10 V or 20 mA).