Module fit and signal conditioning
The Siemens 6ES7355-0VH10-0AE0 is an FM 355 C analog controller module designed for closed-loop control tasks in a S7-300 rack. It accepts 4 analog inputs configurable for thermocouples (Types B, J, K, R, S), Pt 100 RTDs, voltage ranges (-80 mV to +80 mV, -1.75 V to +11.75 V, 0 to 10 V, -10 V to +10 V), and current ranges (0 to 20 mA, 4 to 20 mA, 0 to 23.5 mA, -3.5 mA to +23.5 mA). The input wiring supports 2-wire sensors and parameterizable signal conditioning per channel.
Wiring and isolation constraints
Maximum unshielded cable length is 600 m; shielded runs are limited to 200 m, or 50 m when using the 80 mV range or thermocouples. The module draws 7 mA typical for a signal "1" input and is tested for isolation at 500 V DC between the channels and the backplane bus. There is no channel-to-channel isolation, so common-mode voltage on adjacent inputs must be managed within the -3 to +5 V signal "0" and 13 to 30 V signal "1" thresholds.