The II PD type manual smoke vent button is intended for the controlling
of smoke dampers, providing a simultaneous local 1- or 3-LED light signalling, depending on design.
In the case of a 1-LED signalling, activating the button makes the LED flash red, while pressing the button on a 3-LED signalling system makes the LEDs emit continuous light and indicate the following: detection (green), failure (yellow), and activation (red). The button is equipped with passive electronic components.
The[...]