PLC / Digital I/O, Sensors & Actuators
Investigate a load that appears active while the PLC output is off
A high-impedance load or indicator can respond to leakage or coupling even when the logical command is off. A welded or incorrectly wired circuit is another possibility.
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 command state, module technology, load type and existing diagnostics, then consult the exact output and load specifications.
Interpret the evidence
An indicator glow does not establish available load current or safe isolation. Leakage behavior differs between electronic, relay and protected outputs.
Resolve and verify
Have a qualified technician diagnose the documented circuit under the approved isolation and test plan, then use only manufacturer-approved load-interface remedies.
Machine and data safeguards
Do not touch the circuit, add a guessed resistor or treat a software OFF command as electrical isolation.