SIMATIC S7-300, Digital input SM 321, isolated, 16 DI, 24 V DC, 1x 20-pole, process interrupt, diagnostics, suitable for isochronous mode.
6ES7321-7BH01-0AB0 – SIMATIC S7-30 SM 321, Digital input, 16 DI, 24 V DC
SIMATIC S7-300, Digital input SM 321, isolated, 16 DI, 24 V DC, 1x 20-pole, process interrupt, diagnostics, suitable for isochronous mode