2 analog inputs, 12-bit, 10 mm wide
The Siemens 6ES7123-1FB50-0AB0 is a 2-channel analog input module for the SIMATIC ET 200SP distributed I/O system. It accepts ±10 V signals and digitizes them at 12-bit resolution including sign, with a basic conversion time of 1 ms per channel. The module occupies one slot in an ET 200SP station and draws its 24 V DC supply from the backplane bus, with a typical power loss of 0.6 W. At 10 mm wide, it fits the narrowest slice in the system — useful when panel space is tight and every millimeter of DIN rail counts toward the I/O count.
Input characteristics and filtering
The input resistance is 100 kΩ for the ±10 V range. The destruction limit is 20 V DC continuous or 75 V DC for up to 1 second (duty factor 1:20), so transient protection upstream is still advisable on long cable runs. Digital filtering is parameterizable in four stages to suppress noise on the signal path. The module achieves at least 50 dB crosstalk rejection between inputs at 50/60 Hz and 50 dB common-mode rejection with USS below 2.5 V. Linearity error is ±0.05 % of the input range, temperature drift is ±0.01 %/K, and repeat accuracy at 25 °C is ±0.1 %. These figures keep the measurement stable across the enclosure's thermal gradient.
