Spare-part electronic block for ET 200L
The Siemens 6ES7131-1BH12-0XB0 is a spare-part electronic block for the ET 200L distributed I/O system, providing 16 digital inputs at 24 V DC that are expandable with up to 16 additional channels using the TB 16SC terminal block of Smart Connect. Rated for 24 V DC, it draws a maximum of 180 mA from the supply voltage L+ and 50 mA from the load voltage L+ per load group, with a typical power loss of 4 W.
Input characteristics and sensor compatibility
The module accepts 2-wire sensors and defines signal "1" from 13 to 30 V with a typical current draw of 5 mA, while signal "0" ranges from -30 to +5 V — the permissible quiescent current for a 2-wire sensor is 1.5 mA maximum, which means the sensor's off-state leakage must stay below that threshold to avoid a false-on reading. Input filtering yields a transition time from "0" to "1" between 2 ms and 4.5 ms, and the module supports SYNC and FREEZE capabilities for coordinated acquisition across the ET 200L station.
Diagnostics and isolation
Diagnostics are available, with a bus fault BF (red) LED and a green status indicator per digital input, plus a green LED monitoring the 24 V supply voltage. Channel-to-channel isolation is not provided, but isolation between the channels and the PROFIBUS DP bus is tested at 500 V DC — the module also includes reverse polarity protection on the supply.
Cable lengths and transmission rate
Maximum cable length is 1,000 m shielded or 600 m unshielded, and the PROFIBUS DP interface runs at up to 1.5 Mbit/s. The usable terminal block is the TB 16L, and the module holds a mains/voltage failure stored energy time of 20 ms.