Panel fit and signal routing
The Siemens 6ES7133-1EH00-0XB0 is a digital I/O module for the SIMATIC S7-300 series, packing 8 inputs and 8 outputs into a 145 mm wide housing that's 85.5 mm deep and 61 mm tall. That 145 mm width takes up a fair chunk of DIN rail — plan your gland plate and wireway fill accordingly, because you'll be running 16 field wires plus the backplane bus connector to the adjacent module. Rated for 120 V AC nominal, with signal '1' detection between 74 V AC and 132 V AC. The input current draw sits between 9 mA and 27 mA per channel at signal '1'. That's a healthy AC load on the field side — the module pulls 12.2 W typical power loss, so keep an eye on enclosure ventilation if you're stacking several of these in a row.
Switching speeds and load types
Output switching is asymmetric: resistive loads cycle at up to 10 Hz, but inductive loads drop to 0.5 Hz max. The '0' to '1' transition takes 2 ms minimum, 20 ms maximum; the '1' to '0' edge runs 6 ms to 25 ms. That matters if you're driving contactors or solenoid valves — the off-delay can stack up in a fast sequence. Lamp loads are limited to 1 Hz, so don't plan on strobe or beacon duty without derating. Each output channel handles 0.4 A continuous up to 60 °C ambient — no derating between 40 °C and 60 °C, which is handy in a warm panel. The module has diagnostic capability and a red bus fault LED, so a field tech can spot a missing 24 V backplane or a shorted output without dragging out a meter.