TECHNICAL DATA
January 6, 2012
The Viking Corporation, 210 N Industrial Park Drive, Hastings MI 49058
Telephone: 269-945-9501 Technical services: 877-384-5464 Fax: 269-818-1680 Email: [email protected]
Preaction 328d
2” MoDEL G-2000P PrEACTIoN
wITH ELECTrIC rELEAsE
NoTE:
�iking recommends tank-mounted air com�ressors �or Double Interlock Electric/Pneu-Lectric Release Preaction Systems.
2. Nitrogen Cylinder Gas Su��ly (See Figure 1)
Nitrogen may be used in �lace o� air com�ressors. Nitrogen is su��lied in �ressurized cylinders in various sizes and �ressures.
Some o� the most common are 122 Cu. Ft. at 1,900 PSI (3,455 L at 131 bar), 225 Cu. Ft. at 2,100 PSI (6,372 L at 145 bar), and
280 Cu. Ft. at 2,300 PSI (7,930 L at 159 bar).
When nitrogen cylinders are used as a �rimary air su��ly, s�are cylinders should be �urnished and located at the valve location.
To determine the a��roximate amount o� nitrogen to be �urnished, the �ollowing �ormula may be used:
S�ecial attention must be given to systems em�loying a bottled-gas su��ly. Because only a limited amount o� gas is available,
small leaks, which normally would go unnoticed in systems being su��lied by mechanical com�ressors, can become critical to
the system’s overall �er�ormance. I� the system is to �unction at tem�eratures as low as -40 °F (-40 °C), and, i� bottled nitrogen
is the gas su��ly, the system is �articularly susce�tible to leakage, and s�ecial care should be taken to ensure against leaks
throughout the entire system.
C. Air supply Installation:
1. Install the required air su��ly as described in section 4.B. The size o� the com�ressor and amount o� air required should be
determined in accordance with Tables 1 - 3. The air or nitrogen su��ly to the �reaction system must be clean, dry, and oil �ree.
2. Automatic air su��lies must be regulated, restricted, and �rom a continuous source. A �iking Air Maintenance Device should
be installed on each system equi��ed with a tank-mounted com�ressor, �lant air, or nitrogen. For com�ressors with a ca�acity
less than 5.5 �t
3
/min at 10 PSI (0.154 m
(0.154 m
3
/min at 0.69 bar), NFPA 13 does not require an air maintenance device. In addition,
NFPA 13 does not require an air maintenance device. In addition,
an air maintenance device should not be used with riser mounted com�ressors as this can lead to com�ressor “short cycling”.
�iking recommends that a tank-mounted com�ressor with air maintenance device be used. This can become critical when
This can become critical when
accelerators are installed on the system.
D. Pressure switch wiring:
Wire the Alarm Pressure Switch (PS10) and Air Su�ervisory Switch (PS40), and adjust �ressure settings as shown in Figures 2 - 4.
Figure 4 - Pressure Adjustment
Figure 2 - Alarm Pressure switch wiring
(Alarm Pressure Switch should be set to 5 PSI (0.34 bar)
FIELD ADJUsTMENTs:
Alarm Pressure switch:
The o�erating �oint o� the switch can be
adjusted to any �oint between 4 PSI (0.27 bar) and 8 PSI (0.55 bar)
by turning the adjustment knob(s) clockwise to raise the actuation
�oint or counter-clockwise to lower the actuation �oint.
Air supervisory switch:
The o�erating �oint o� the switches can
be adjusted to any �oint between 10 PSI (0.7 bar) and 60 PSI
(4.1 bar) by turning the adjustment knob(s) clockwise to raise the
actuation �oint or counter-clockwise to lower the actuation �oint.
The high and low switches are adjusted inde�endently.
Metric Units
�c =
�s x P
where:
�c = �olume o� Cylinder (L)
P = Required Nitrogen Pressure (bar)
� = �olume o� System (L)
108
Figure 3 - Air supervisory switch wiring
single Interlock
Double Interlock
English Units
�c =
�s x P
where:
�c = �olume o� Cylinder (�t
3
)
P = Required Nitrogen Pressure (PSI)
� = �olume o� System (gal)
100