PLCs are the layer where warehouse automation actually meets the physical world — every conveyor motor start, every shuttle drive command, every safety interlock check runs through PLC logic. They're built for reliability in harsh industrial environments and typically run continuously for years without a restart.
PLC fault codes and diagnostic logs are one of the richest, most underused sources of early-warning maintenance data available: a PLC logging repeated fault-and-reset cycles on a drive is usually reporting a developing mechanical problem well before it becomes a hard stop, if anyone's watching for the pattern.