Stack light

Stack lights are used in similar applications to beacon lights/strobes, however the information they typically display encompasses more machine/process conditions.

A stack light will typically have up to five differently coloured segments to indicate various conditions on the machine or process.

Segments in any combination of (typically) red, yellow, green, blue or clear white are actuated independently and are either off, steadily lit, or flashing.

Discrete signals activate illuminated segments at common industrial control voltages (including 12Vdc, 24Vac/dc, 115Vac, 230Vac).

Stack lights are used in a variety of machines and process environments; specific colour-coding is assigned by the system designer.

Stack light in automated production for in-line quality inspection
Various size stack lights
Demonstration by technician in Colgate Palmolive of how the Andon Button works