Heptafluoropropane pressure signal, providing a pair of switch contacts, heptafluoropropane pressure signal in the system unit is independently mounted on the manifold, the combination of the distribution system, mounted on the respective selection valve outlet or downstream of the main pipe. Heptafluoropropane pressure signal is to be installed in the manifold downstream of the valve stem or select pipe required to connect the seat welding, and to ensure its connectivity. Normally open contact micro switch, when you release the extinguishing agent, the pressure within the pipe network to promote the feedback device in the piston so that the micro switch is turned on, outside the protection zone extinguishing the discharge lights, and a feedback signal to the fire control center, The show has been the implementation of fire protection zone. Heptafluoropropane pressure signal within piston head with micro switch touch distance adjustable reed (unscrew the cover, rotating mounting screw micro switch).