Overview
The 6ES7123-1GB00-0AB0 is a Siemens SIMATIC SC electronic submodule, designated as a spare part, providing two analog inputs for 4-20 mA and ±20 mA current signals with 13-bit resolution on the ±20 mA range and 12-bit on the 4-20 mA range. It draws 0.6 W from the backplane, offers 1500 V isolation test voltage, and mounts on the TB 16SC terminal block for integration into a SIMATIC SC I/O station.
Function & operation
This submodule converts two analog current signals — either 4-20 mA or ±20 mA — into digital values for the controller. The integrating measurement principle with a basic conversion time of 55 / 65 ms (50 / 60 Hz) rejects line-frequency noise, and the integration time is parameterizable in four stages via digital filtering for additional noise suppression. Resolution is 13 bits on the ±20 mA range and 12 bits on the 4-20 mA range, with linearity error of 0.05 % and temperature error of 0.01 %/K. Reverse-polarity protection is built in, and common-mode rejection is 90 dB.
Applications
As a spare part for the SIMATIC SC system, this submodule fits into existing I/O racks where a 2-channel analog current input is needed — typically in process instrumentation loops for pressure, level, or flow transmitters transmitting 4-20 mA signals back to a PLC or DCS.