Tyco DV-5A - System Air Pressure Requirements

TFP1450
Page 9 of 28
WARNING
If the delay between electric actua-
tion and subsequent sprinkler activa-
tion is anticipated to be greater then
10 minutes, adjust the battery back-up
calculation accordingly. Inadequate
battery back-up may result in failure of
the system to operate in the event of a
fire during a power failure.
System Air Pressure Requirements
The required system air pressure for
the Double Interlock Preaction System
with Electric/Pneumatic Actuation is
shown in Graph B as a function of the
anticipated water supply pressure. It is
recommended that the system air pres-
sure be maintained by one of the fol-
lowing methods:
• A maximum 200 psi (13,8 bar) plant
air supply in combination with the
Model AMD-1 Air Maintenance
Device described in Technical Data
Sheet TFP1221
• A dedicated air compressor in com-
bination with the Model AMD-2 Air
Maintenance Device described in
Technical Data Sheet TFP1231
Notes:
The dew point of the pilot line air pressure must be maintained
below the lowest ambient temperature to which the dry pilot
actuation system will be exposed. Accumulation of water in the
pilot line connection to the Actuator will lower the air pressure
at which the actuator will open and possibly prevent proper
operation. Also, introduction of moisture into the pilot lines
exposed to freezing temperatures can create an ice buildup
that could prevent proper operation of the Actuator.
An air dryer must be installed where the moisture content
of the air supply is not properly controlled at less than the
required value.
It is recommended that an AMD-3 Nitrogen Maintenance
Device be utilized in dry pilot actuation system applica-
tions where the dew point must be maintained below -20°F
(-29°C). Refer to Technical Data Sheet TFP1241.
• A maximum 3000 psi (206,9 bar)
nitrogen cylinder in combination with
the Model AMD-3 Nitrogen Mainte-
nance Device described in Technical
Data Sheet TFP1241
NOTICE
The dew point of the air or nitrogen
supply, for a system exposed to freez-
ing conditions, must be maintained
below the lowest ambient tempera-
ture to which the system piping will be
exposed. Introduction of moisture into
the system piping can create ice build
up which could prevent proper opera-
tion of the system.
The Air Pressure Relief Valve is typi-
cally set to crack open at 5 psi (0,34
bar) greater than the required system
air pressure provided in Graph B.
WATER SUPPLY PRESSURE IN PSI
100
RANGE OF ACTUATOR OPENING PRESSURE
MINIMUM SYSTEM AIR PRESSURE
AIR PRESSURE IN PSI
20 60
15
0
30
45
140 180
250
200
GRAPH B
DV-5a VALVE DOUBLE INTERLOCK PREACTION SYSTEM
AIR PRESSURE REQUIREMENTS