Green check: Steady means normal; slow blinking is standby. Red/yellow alert: Steady red = serious fault (stop high – power use); blinking red = minor fault (fix soon); steady yellow = low voltage (avoid high – power); blinking yellow = temporary issue (wait or contact if lasting). A Step-by-Step Guide to Reading Power Status via the Four-Color Lights in Civil Distribution Boxes - NEWJIELI From “Confused” to “Understood in Seconds”! A Step-by-Step Guide to Reading Power Status via the Four-Color Lights in Civil Distribution Boxes Check the box's label first. If not, use this. In this post I have explained 5 useful power supply failure indicator circuits which can be used to get an instant indication regarding an input power failure situation. This simple circuit can help us to take appropriate. IEC does not mandate a single required color for distribution panel indicator lights, but standards provide guidance through EN 60204-1:2018 (Safety of machinery - Electrical equipment) and IEC 60417 (Graphical symbols for use on equipment). They indicate the presence of voltage, system status, and fault conditions through color-coded illumination.