Features:
- Three channels organize rapid/slow traverse positioning on one S7-400 module.
- Each axis receives four inputs and four short-circuit-protected outputs.
- Incremental and SSI encoder paths cover pulse and absolute feedback formats.
The three-channel structure keeps cam inputs, encoder feedback and travel commands aligned by axis.
Output states distinguish rapid traverse, creep and the two travel directions for each connected drive.
Potential separation applies to both digital-input and digital-output groups before the 48-pin field connector.
The Siemens 6ES7451-3AL00-0AE0 FM 451 Positioning Module may still be available for purchase and support from Apter Power beyond End-Of-Life (EOL) by the manufacturer (OEM).
Siemens 6ES7451-3AL00-0AE0 FM 451 Positioning Module Manuals,Datasheets,Link
Important Notice: Other accessories, manuals, cables, calibration data, software, etc. are not included with this equipment unless listed in the above stock item description. All prices are shown in USD.
Keeping three motion channels distinct
- Channel Count: Three positioning channels share the FM 451 hardware.
- Input Partition: Four digital inputs are assigned to each axis.
- Output Partition: Four digital outputs are assigned to each axis.
- Field Boundary: The combined axis signals terminate through one 48-pin connector.
Matching pulse and absolute feedback
- Differential Incremental: A, not-A, B, not-B, N and not-N signals run to 1 MHz.
- Single-Ended Incremental: A, B and N use 24 V signaling with a rate tied to cable length.
- Absolute Feedback: SSI accepts differential DATA and clock pairs.
- Code Format: SSI telegrams use 13 or 25 bits and support Gray code.
Position-reference signal flow
- Reference Cam: One input function establishes the axis reference event.
- Reversing Cam: A separate input function marks the travel reversal boundary.
- Actual-Value Capture: Flying actual-value setting records the moving position reference.
- Sequence Control: Start and stop positioning complete the documented input set.
Converting a target into drive states
- Rapid Command: One output selects rapid traverse for the active axis.
- Creep Command: A separate output selects the slower approach state.
- Right Direction: Run-right is issued independently of the speed selection.
- Left Direction: Run-left provides the opposite travel command.