The 6ES7551-1AB00-0AB0 is a TM PosInput 2 module for the S7-1500 system, accepting incremental and absolute encoders over RS-422 or 5 V TTL push-pull signals. Supply rails are 5.2 V ±2 % and 24 V L+ (-0.8 V), drawn from the backplane — no auxiliary supply needed. The 35 mm wide housing occupies one slot on the S7-1500 mounting rail.
Lifecycle and ordering
Order through standard Siemens distribution; no alternate sourcing or cross-reference is required.
Dimensions are 129 mm depth, 147 mm height, 35 mm width — verify cabinet clearance for signal wiring depth. Input data consumes 16 bytes per channel for position; outputs use 12 bytes per channel plus 4 bytes for motion control. Built-in diagnostics cover wire-break and short-circuit; the monoflop time is parameterizable from 16 to 64 µs or set to automatic.