Single-channel output with Fast mode and Motion Control
The Siemens 6ES7138-6AA00-0BA0 is a one-channel digital output module for the ET 200SP distributed I/O system. It handles a single 24 V DC output, with the L+ supply dropping up to 0.8 V under load — something to account for in voltage-sensitive loads like valve coils or indicator lamps. The module packs 16 bytes of input data space and 12 bytes of output data space. In Fast mode — enabled from firmware V1.2 or higher — the input data shrinks to 4 bytes and output data to 0 bytes, freeing bandwidth for high-speed signal processing. Motion Control uses 4 bytes of the output region, so if you are running both Fast mode and Motion Control, watch the data allocation.
Panel fit and wiring constraints
The module is 15 mm wide, 73 mm tall, and 58 mm deep — it clips onto the DIN rail with a BU type A0 BaseUnit underneath. That 15 mm width is tight for a crowded enclosure; you can fit several per row without eating up rail space. Input voltage is rated at 24 V DC, with signal '1' threshold from +11 to +30 V and signal '0' from -5 to +5 V. The module draws about 1 W typical power loss. Wiring runs up to 1 000 m shielded or 600 m unshielded.