Industrial Indicator Light Color Standards and Usage Guidelines
ONPOW has published a technical guide on industrial indicator lighting, emphasizing the necessity of adhering to IEC standards for machine safety and operator clarity.
Indicator lights in industrial settings serve as primary interfaces for communicating machine status. According to a guide released by ONPOW, the assignment of light colors is not a matter of design preference but must adhere to established conventions, specifically referencing IEC 60073 and IEC 60204-1. These standards ensure that visual signals remain consistent across different equipment and facilities.
The industry convention typically utilizes red to signal emergencies or critical faults, while amber or yellow denotes abnormal conditions requiring attention. Green is reserved for normal and safe states, blue for specific operator actions, and white for general information. ONPOW warns that color alone is insufficient for communication; every indicator must be paired with clear, written labels and verified feedback signals from the machine's control logic.
A significant issue identified in the guide is the reliance on command-based signaling rather than verified feedback. For example, a green indicator for 'motor running' should ideally be triggered by an actual feedback sensor rather than a PLC output command. This distinction ensures that the light accurately reflects the mechanical state rather than the intent of the control system.
The firm stresses that proper panel design requires a systematic review of the control sequence, risk assessment, and customer requirements. By standardizing these visual inputs, manufacturers can reduce human error and improve the diagnostic process for operators.