32 inputs, expanded temperature range, end-of-life
The Siemens 6ES7321-1BL80-0AA0 is a SIMATIC S7-300 SM 321 digital input module providing 32 optically isolated inputs at 24 VDC, designed for the expanded temperature range variant of the S7-300 family.
Input ratings and derating
The 32 digital inputs are rated for signal '1' from 13 to 30 V, with a typical current draw of 7 mA per input at the rated 24 VDC. At ambient temperatures up to 40 °C, all 32 inputs are available; above 40 °C up to 60 °C, the module derates to 16 inputs maximum. Input filtering is specified with a minimum turn-on time of 1.2 ms and a maximum of 4.8 ms from signal '0' to '1'.
It requires a 40-pin front connector for field wiring, and the backplane bus draws a maximum of 15 mA from the 5 V DC rail. Optocoupler isolation is provided between the channels and the backplane bus, with 500 V DC tested isolation.