SM 338 ultrasonic position decoder for S7-300 racks
The Siemens 6ES7338-7UH00-0AC0 SM 338 is an ultrasonic position decoder module for the S7-300 family. It reads position from ultrasonic measuring devices that use a start/stop interface, such as those from Balluff or MTS. This module decodes the time-of-flight signal from the ultrasonic transducer into a position value the PLC can process — no separate counter card or external converter needed for that interface type.
EOL hot — sourcing window narrows
For a replacement path, the buyer needs to evaluate the current S7-1200 or S7-1500 technology modules that accept incremental encoder or SSI inputs, and map the ultrasonic sensor interface accordingly.