SIMATIC S7-400, digital input SM 421, isolated 16 DI; UC 24 – 60 V, alarm, diagnostics...
SIMATIC S7-400, digital input SM 421, isolated 16 DI; UC 120/230V Inputs according to IEC1131-2 Type 2...
SIMATIC S7-400, digital input SM 421, isolated 32 DI; 120 V DC/AC...
SIMATIC S7-400, digital input SM 421, isolated 32 DI; 24 V DC...