Technical data

2.2.3 Solenoid Valve
A normally closed electric solenoid valve is a primary control
valve releasing device when located on the discharge outlet
of the hydraulically pressurized push rod chamber of the Mod-
el DDX Deluge Valve. The solenoid valve separates water
pressure in the pushrod chamber from atmospheric air pres-
sure in a drain line. When sufficient electrical current is provid-
ed to energize the solenoid valve coil (from a listed releasing
panel), the solenoid valve opens and discharges water pres-
sure from the pushrod chamber to a drain. Since the pressure
cannot be replenished through the inlet restricted orifice as
rapidly as it is discharging, the push rod chamber pressure
falls instantaneously and the Model DDX Deluge Valve opens.
Refer to Reliable Automatic Sprinkler Company Bulletin 718
for more detailed information on the solenoid valve specifica-
tions.
2.2.4 Dry Pilot Actuator
A dry pilot actuator uses the same differen-
tial principle as a conventional dry pipe valve
wherein low pneumatic pressure holds the
device closed against considerably higher
water pressure. The actuator is connected to
the Model DDX Deluge Valve pushrod cham-
ber outlet port. When a dry pilot line detec-
tor activates, a manual station is opened, or
(in the case of the low pressure dry system),
system pressure is lost, water pressure on the
underside of the dry pilot actuator overcomes
the reduced air or nitrogen pressure on the
top side of the actuator. The actuator opens
allowing the push rod chamber pressure to
discharge through the actuator to a drain
outlet. Since the pushrod chamber pressure
cannot be replenished through the inlet re-
stricted orifice as rapidly as it is discharging,
the push rod chamber pressure falls instan-
taneously and the Model DDX Deluge Valve
opens.
Technical information for the LP actuator is found on the Re-
liable Automatic Sprinkler Company bulletin for each system
where it is utilized.
2.2.5 Manual Release
A manual release or pull station is a normally closed, quick
opening valve which acts as a system releasing device when
located in the piping of a wet or dry pilot line of sprinklers. It dis-
charges hydraulic or pneumatic pressure from the pilot line, just
as an automatic pilot line detector or sprinkler would do. The
Model A pull station valve is enclosed in a labeled steel box that
has a cover held closed by a breakable strut. Once opened,
the cover will not stay closed unless the strut is replaced.
Refer to Reliable Automatic Sprinkler Company Bulletin 506 for
detailed information on the Model A Manual Hydraulic Emer-
gency Pull Box.
2.3 Pneumatic Pressure Supervision
With the exception of electric and wet pilot operated deluge systems
and non-supervised single interlock preaction systems, all special
systems use pneumatic pressure for either (or both) supervising the
integrity of the system or as a trigger for system operation. Com-
pressed air or nitrogen are the two most common gases used to sup-
ply pneumatic pressure.
Figure 25
28.
Figure 26
Figure 27