PLC / Drives, Motion & Axis Diagnostics
Find a drive or PLC limit that clamps the requested speed
A requested speed can differ from the accepted value because one of several configured limits or operating modes constrains it.
Environment and inputs: Industrial PLC / automation guidance · Verify the exact controller, module, firmware, engineering tool and machine documentation. Linked vendor examples apply to their stated products and library versions; observation, state changes and physical work require distinct authorization.
Observe and record
Record the PLC request, drive-received reference, active limit indications and approved speed-related parameter layers.
Interpret the evidence
The lowest effective limit may come from recipe, axis, drive or process logic. A communication value being correct does not prove the final request is unconstrained.
Resolve and verify
Correct only a demonstrated unapproved mismatch and validate the supported speed envelope through the machine's test process.
Machine and data safeguards
Do not raise maximum speed, defeat a safety limit or override mechanical ratings to make a setpoint track.