Victaulic FireLock NXT 764 Series User Manual

AIRSUPPLYREQUIREMENTS
The required air pressure for Series 768 FireLock NXT Dry Valves is
13 psi/90 kPa/0.9 Bar minimum, regardless of the system supply water
pressure. Normal air pressure should not exceed 18 psi/124 kPa/1.2 Bar.
Failure to maintain air pressure within the 13 psi/90 kPa/0.9 Bar to
18 psi/124 kPa/1.2 Bar range may reduce system operation response
time.
Systems with air pressure higher than 18 psi/124 kPa/1.2 Bar may
require the addition of a Series 746-LPA Dry Accelerator. NOTE:
The Series 746-LPA Dry Accelerator must be used only on systems
operating below 30 psi/206 kPa/2.1 Bar of air. If air pressure higher
than 30 psi/206 kPa/2.1 Bar is required, the Series 746 Dry Accelerator
should be used.
FORVdSAPPROVEDVALVESONLY: The minimum air pressure for
Series 768 FireLock NXT Dry Valves installed with Series 746-LPA Dry
Accelerators shall be 16 psi/110 kPa/1.1 Bar. The maximum air pressure
shall be 19 psi/130 kPa/1.3 Bar.
If multiple Series 768 FireLock NXT Dry Valves are installed with a
common air supply, isolate the systems with a spring-loaded, soft-
seated ball check valve to ensure air integrity for each system. Good
practice is to include a ball valve for isolation and service of each
individual system.
The engineer/system designer is responsible for sizing the compressor
so that the entire system is charged to the required air pressure within
30 minutes. DO NOT oversize the compressor to provide more airflow.
An oversized compressor will slow down or possibly prevent valve
operation.
If the compressor fills the system too fast, it may be necessary to
restrict the air supply. Restricting the air supply will ensure that air
being exhausted from an open sprinkler or manual release valve is not
replaced by the air supply system as fast as it is being exhausted.
COMPRESSORSIZING
0
2
4
6
8
10
12
System Capacity (in gallons)
Required Flow Rate (CFM)
COMPRESSOR REQUIREMENTS
550 300
50
800
1050 1300 1550 1800
20 psi/138 kPa
13 psi/90 kPa
BASEORRISER-MOUNTEDAIRCOMPRESSORS
For base or riser-mounted air compressors, the recommended air
pressure of 13 psi/90 kPa/0.9 Bar is the “on” or “low” pressure setting
for the compressor. The “off” or “high” pressure setting should be
18 psi/124 kPa/1.2 Bar.
When a base or riser-mounted air compressor supplies air to a Series
768 FireLock NXT Dry Valve, it is not necessary to install the Victaulic
Series 757 Regulated Air Maintenance Trim Assembly (AMTA). In this
case, the air line of the compressor connects to the trim at the fitting
where the Series 757 Regulated AMTA is normally installed (refer to
the applicable trim drawing). If the compressor is not equipped with a
pressure switch, the Series 757P Air Maintenance Trim Assembly with
Pressure Switch should be installed.
SHOPAIRORTANK-MOUNTEDAIRCOMPRESSORS
In the event a compressor becomes inoperative, a properly sized tank-
mounted air compressor provides the greatest protection for systems.
When shop air or a tank-mounted air compressor is used, the Series
757 Regulated AMTA must be installed. The Series 757 Regulated
AMTA provides proper air regulation from the air reservoir to the
sprinkler system.
For tank-mounted air compressors, the recommended air pressure
of 13 psi/90 kPa/0.9 Bar should be used as the set point for the air
regulator. The “on” pressure of the compressor should be at least 5 psi/
34 kPa/0.3 Bar above the set point of the air regulator.
VICTAULICSERIES757REGULATEDAIRMAINTENANCETRIM
ASSEMBLY(AMTA)OPTION
NOTICE
VictaulicrecommendsamaximumoftwoSeries768FireLock•
NXTDryValvesperSeries757RegulatedAMTA.
1
6
5
4
2
3
Bill of Materials
1 ⁄"/3.2 mm Restrictor
2 Slow Fill Ball Valve (Normally Open)
3 Air Regulator
4 Strainer (100 Mesh)
5 Spring-Loaded, Soft-Seated
Ball Check Valve
6 Fast Fill Ball Valve (Normally Closed)
I-768_9
FireLockNXT™DryValve
SERIES768
I-768INSTALLATION,MAINTENANCE,ANDTESTINGMANUAL
www.victaulic.com
VICTAULIC IS A REGISTERED TRADEMARK OF VICTAULIC COMPANY. © 2007 VICTAULIC COMPANY. ALL RIGHTS RESERVED. PRINTED IN THE USA.
REV_D

Victaulic FireLock NXT 764 Series Specifications

General

Brand	Victaulic
Model	FireLock NXT 764 Series
Category	Control Unit
Language	English