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1.0 BALANCED PRESSuRE PROPORTiONER (CCS) ENviRONMENT
There are numerous ways in which the fire protection engineer can design a system using a Viking Concentrate Control
system (CCs). The method he chooses must take into consideration the CCs specifications.
The outer tank is AsME constructed at a design or working pressure of 175 PsI, and is hydrostatically tested at 263
PsI.
The inner tank (bladder) is fabricated of a flexible fabric, Buna-N® over nylon, Mullen burst 800 pounds (relative to area
and pressure), tensile (grab) 400 pounds X 450 pounds.
Forces such as waterhammer - expansion/contraction of the contents in the CCs - valve arrangement, pressure relief
valves, concentrate specifications, etc., could affect the operation of the system.
Any design or manipulation of valves that will cause a significant pressure differential across the bladder should be com-
pensated for or avoided.
It is the responsibility of the design engineer to accommodate the CCs in an environment compatible with its specifica-
tions.
2.0 CONTROLLER iNSTALLATiON & OPERATiON
iMPORTANT:
DO NOT ALTER iNTEGRAL PiPiNG WiTHOuT CONSuLTiNG WiTH A SYSTEM DESiGN
REPRESENTATivE. PiPiNG ALTERATiON CAN iNFLuENCE SYSTEM PERFORMANCE. BEFORE iNSTALLiNG A
"CONCENTRATE CONTROLLER," CHECK YOuR SYSTEM DESiGN DRAWiNG TO ENSuRE THE LOCATiON DOES
NOT ADvERSELY AFFECT THE PROPORTiONiNG DuE TO EXCESSivE LOSS OR FRiCTiON LOSS.
CHECK THE PERCENT STAMPiNG ON THE CONTROLLER TO ASSuRE THAT YOu HAvE THE CORRECT
CONTROLLER FOR THE SYSTEM.
It is recommended that a length of straight pipe, equal to 4-6 pipe diameters, be installed immediately before and after the
"Concentrate Controller". This will help eliminate the possibility of turbulence affecting the proportioning accuracy. Install
the controller with the Viking pointing in the direction of the water flow.
The ideal location of the controller is level with the top discharge, and within a couple feet of the tank. Actual field condi-
tions, however, will not always allow for this design. The controller will still proportion as intended in a wide variety of
locations, providing the design is made with the operating characteristics of the controller in mind.
Mounting above the discharge level or long distances from the CCs will affect the low flow performance of the control-
ler by raising its low flow minimum. Mounting the controller below the discharge lowers its minimum flow requirement;
however, sPECIAL PRECAUTIONs ARE REQUIRED TO PREVENT CONCENTRATE MIGRATION INTO THE WATER
sUPPLY.*
The concentrate controller is a modified venturi device. As water flows through the venturi, it creates an area of lower
pressure, referred to as the metering pressure drop. The faster the water flows through the venturi, the higher the me-
tering pressure drop. This allows more concentrate to enter through the orifice to mix with the increasing water flow. A
decrease in water has the opposite effect on the metering pressure drop, thereby reducing the amount of concentrate
passing through the orifice.
Moving the concentrate out of the tank to the controller incurs some friction loss. The low flow rating of the controller is
that point where the metering pressure loss created by the flow of water across the venturi is now greater than the total
friction loss incurred by the concentrate moving to the controller.
This figure is obtained by calculating the friction loss of the interconnection piping. This includes the water supply piping
to the tank and the concentrate discharge pipe to the controller. This figure is then added of the pressure loss incurred
within the bladder itself - approximately 1 PsI.
2
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