Siemens 6ES7550-1AA01-0AB0 SIMATIC S7-1500 TM Count 2x24V 800kHz PLC I/O Module

The Siemens SIMATIC S7-1500 TM Count 2x24V technology module (6ES7550-1AA01-0AB0) provides 2 independent counter channels for 24 V incremental or pulse encoders, each reaching 800 kHz counting frequency with quadruple evaluation from a 200 kHz raw input. Each channel also adds 3 digital inputs and 2 digital outputs for gating, capture, and comparator-driven switching.

Technical Specifications

Selection Notes

Two independent 24 V counter channels each handle 800 kHz with quadruple evaluation, four times the 200 kHz raw input frequency, which covers most incremental encoders used for length and position feedback without an external counter card. Each channel carries its own 3 DI / 2 DO set for gate start/stop, capture, and comparator-triggered switching, so channel-level logic such as stop-on-position runs without added CPU cycle latency. A shared 24 V encoder supply rated at 1 A total powers both channels, so check combined encoder current draw against that budget before wiring two encoders at once.

Applications

Position and length measurement on S7-1500 Motion Control axes, cut-to-length machines, and packaging equipment that use incremental or pulse encoders and need channel-level gating or capture without CPU involvement.