SIPLUS PCS 7 SM 321 16DI based on 6ES7321-7TH00-0AB0 with conformal coating, 0…+60 °C, digital input 16 DI; 24 V DC, 1x 40-pole, diagnostics-capable, for contacts (wired/ not wired), NAMUR encoder, 3/4-wire BERO, with chatter monitoring; pulse stretching, open-circuit detection connection IM 153-2 required Just like the CPU, the digital input modules are also protected against extreme ambient conditions. Due to the 100% conformal coating they can withstand biologically, chemically and physically active substances, condensation, frost, and corrosive gases. Regardless of the conditions, your digital signals are reliably recorded.