FPS-DIE0
The Pre-action system is a fire protection (FP) combined system, consisting of a controlled FDV deluge valve and a riser check valve installed downstream. The pressurized automatic sprinkler pipeline maintains the riser check valve in a closed position. The section between the downstream side of the closed deluge valve and the check valve clapper functions as the “intermediate chamber,” where the water pressure switch and the acoustic alarm are connected.
In double-interlock pre-action systems, such as the FPS-DIE0 described here, full system activation depends on the occurrence of two independent, fire-related events: one caused by heat exposure and the other by fire detection. The activation of the FPS-DIE0 system requires two electrical signals.
In the event of a fire, heat causes one or more automatic sprinklers to open, resulting in a drop in pressure within the sprinkler pipeline. This pressure drop activates the air pressure switch, which sends a signal to the main control board. This constitutes the first actuation event.
At this stage, a normally closed solenoid valve located on the deluge valve’s control chamber drain line remains closed.
When one or more Electric detectors are triggered, they send an electrical signal to the main control board, constituting the second actuation event. Only when both actuation events have occurred does the control board energize the solenoid valve, thereby opening the FDV deluge valve and allowing water to flow into the sprinkler pipeline.
The trim is equipped with a PSA – a device that enables the local reset of the system i.e. closing the FDV valve by pressurizing the valve’s control chamber.
In addition, the PSA is considered as a latching device that keeps the valve open even in case of power outage.
