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K factors are used as multipliers to determine total flow out of a hydrant when the portable flow and
pressure meter is hooked up to only one port of the hydrant, but water is flowing out of more than one.
If your portable tester has a different size flow tube, then the K factors used to determine total flow out
of the hydrant will be different than those shown. K factors for different possibilities are based on the
following formula:
constant K
= Total Flow Area
Area of Flow Tube opening
Total Flow Area means finding the sum of the areas of all open discharges.
Remember the Area of a circle is л r2 (л = 3.14, r = radius of the tube)
K factors are used as multipliers to determine total flow out of a hydrant when the portable flow and
pressure meter is hooked up to only one port of the hydrant, but water is flowing out of more than one.
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Water Distribution System Test
This test will determine the flow rate available at a particular location for fire fighting purposes, at the
desired mains residual pressures. This is the available flow rate of the distribution grid, at that location,
with one or more hydrants being used simultaneously.
In performing these tests, follow the recommendations outlined in the FIRE FLOW TESTS section
of "FIRE SERVICE HYDRAULICS" second edition. Also consult the
"FIRE PROTECTION HANDBOOK"
15th edition of the NFPA.
Generally the procedure is as follows:
- Select two adjacent hydrants, one to be the flow hydrant and the other to be the static hydrant.
- Assign a man to each hydrant. Attach a cap, complete with a pressure gauge to one of the 2.5
inch (65mm) outlets on the static hydrant. Connect the Portable Flow and Pressure Meter to one
of the 2.5 inch (65mm) outlets on the flow hydrant
- Ensure that all port caps are shut tight. Then open the static hydrant and bleed off the air through
the pet cock on the gauge. Close the pet cock and record the static pressure
- Open the flow hydrant fully. When the pressure gauge on the static hydrant levels out (holds
steady), record the residual pressure at the static hydrant and the flow reading displayed by the
Portable Flow and Pressure Meter at the flow hydrant.
- If the residual pressure at the static hydrant has dropped a minimum of 10 psi from the no flow
pressure measurement, no additional testing is required in order to obtain the local grid
characteristics. However, if the residual pressure drop was less than 10 psi additional ports or
hydrants may be opened. This will also allow more accurate predictions. To do that shut down
the flow hydrant, open the additional port, and repeat tests starting from
"c" above.
- If additional ports are opened, it is assumed that the flow from each port is in proportion to the
area of its opening. Refer to section "Hydrant Total Flow Test" to figure out the total flow.
Calculation of Results
The test results may now be used to calculate the total flow in the local distribution system (mains)
at the recommended minimum value of 20 psi.
The Hazen-Williams equation written in the form
QR = QF x HR
HF
is used to calculate total maximum allowable flow at the minimum desired pressure.
The symbols in the equation are interpreted below:
QR = The total flow in GPM at the desired residual pressure (generally 20 psi)
QF = The test flow of the flow hydrant
HF = The loss of pressure in psi at the static hydrant
To obtain HF subtract the residual pressure on the static hydrant from the static pressure at no flow.
HR = Pressure drop in psi to the desired residual pressure.
To obtain HR subtract the desired residual pressure (generally = 20 psi) from the static hydrant
pressure at no flow.
To use the Hazen-Williams equation, raise HR and HF to the 0.54 power using a calculator.
Then a simple substitution of the values in the equation will yield QR, the maximum available flow at
the desired residual pressure.
In interpreting the results of these tests, it should be remembered that they show the strength of the
distribution system and do not necessarily indicate the degree of adequacy of the entire water system.
In this connection it is important to check the facilities supplying the distribution system and determine
the length of time the discharges indicated by the tests can be maintained.
Values of H ( HR or HF ) to the 0.54 power.
EXAMPLE: Test data obtained:
- Static pressure = 78 PSI
- Residual pressure at the static hydrant during the flow test = 50 PSI
- PFPM reading with one additional 2.5" port opened = 455 GPM
- The PFPM has a 2.5" discharge opening and a flow area of 4.9 sq. inches. The flow area of
the other openings flowed can be obtained by using the following equation.
A = D2 x µ where µ =
3.14
4
A = 0.785 x D2 where "D" is the
inside diameter of the opening in inches.
A hydrant with a 2.5" opening has an area of 4.9 sq. inch and a steamer port with a diameter of 4.5
inches has an area of l5.9 sq. inch. The PFPM has a choke area of 4.9 inch, therefore with a 2.5" port
opened in addition to the one the PFPM is mounted on then the test flow (Qf) equals:
Test flow (Qr) = Flow Reading (FR) x
Total Flow Area
Area of the PFPM
Test flow (Qr) = FR x (4.9 + 15.9)
(4.9)
Test flow (Qr) = FR x 4.24
e. Selected minimum residual pressure in
the mains = 20 PSI.
Calculations
a. Test flow (Qr) = 4.24 x 455 GPM =
1929 GPM
b. Hr = pressure drop during test = 78-50 = 28 psi
c. Hr = pressure drop to desired residual pressure = 78 - 20 = 58 PSI
d. Total flow (Qr) = Qr x Hr054
Hr054
then Qr = 1929 x 58054
28054
(where 58054=8.96 and 28054= 6.05)
Therefore Qr = 1929 x 8.96
6.05
Qr = 2857 GPM
USE OF TEST RESULTS
The information developed from a set of flow tests, if properly used, can be of considerable help to
both the fire and water departments of a municipality. Because the quantities of water available at
various locations are known, chief officers of the fire department should be able to deploy the pumpers
responding to a fire in a given area to the best advantage. They will know the strong points of the
distribution system where the supply is sufficient for numerous pumpers, as well as the weak spots
where not more than one or two pumpers can be used effectively.
Since test results will reveal the weak points in a water distribution system, they can be used by the
water department to determine where and to what extent improvements are needed. They are also
helpful in providing data which can be used in estimating the supply available for extensions into newly
developing areas.
When tests are repeated after a number of years at the same location and under similar conditions,
a comparison of the results may show decreased quantities available because of tuberculation of
mains, increased consumption, or both. If such warnings are needed, the necessary steps can be
taken to provide additional distribution capacity before the available quantities become seriously
inadequate. In a similar manner, repeated tests can be used to determine the increased quantities that
may be available in areas where improvements have been made.
In reviewing flow tests results and comparing them with results obtained by other methods of
analysis, it is often found that certain sections of a distribution system are not delivering their full
capacity. This indicates that there are either restrictions somewhere in the mains or that one or more
valves may be inadvertently closed. It points out the need for a physical check on the mains and valves
in the vicinity of the test. Many closed valves in distribution systems have been located as a result of fire
flow tests.
B) Pump Tests
The Portable Flow and Pressure Meter can be used to test pumpers not only from draft but also
from the tank or from a hydrant. It is extremely valuable to know not only that your pumper can pass the
service test, but remember it is necessary to know your capabilities on the fire ground.
Make sure your pump can supply your pre-connected lines with enough water from the tank, if that is
the way you expect to use them.
For in-line pump testing, attach the portable tester to the hydrant and run a typical hose layout. Next,
extend your standard fire fighting lines and open them. Monitor the flow and pressure.
For the service type of test, connect three lines into a common manifold. On the discharge of the
manifold connect a short length of hose leading into the portable tester. Attach another length of hose
on the discharge side and connect this to a deck gun or monitor. If the monitor incorporates a sufficient
straight length, with an integral stream straightner, then the portable tester may be attached on to the
discharge end of the monitor in lieu of the nozzle.
Then test the pumper according to the certification pressure, RPM, and volume or pressure pump
settings. To do that, set the RPM and then adjust the pump pressure by adjusting the discharge valves.
Correct the RPM if it has changed; and readjust the pressure if that has changed. When you are at the
correct pressure and RPM point, note the flow. The flow should meet the pumper rating at that pressure
and RPM.
C) Nozzle Tests
Attach a hose to the Portable Flow and Pressure Meter flow tube inlet and the nozzle to be tested on
the discharge of the flow tube. The nozzle may be either a smooth bore type or automatic. Flow the
nozzle at various pressures and note the flow and pressure displayed on the readout. This test will
provide a vivid depiction of the nozzle pressure/flow relationship.
D) Training
Use the Portable Flow and Pressure Meter in training sessions to show firemen the effects of
pressure and flow on hose handling, reach of stream, the effects of kinked hose, etc. as pumper
pressure and nozzle sizes are changed.
Install the flow tube in the line behind the nozzle, preferably not directly on to the discharge port of
the pumper. With the nozzleman varying the nozzle and the pump operator varying the valves, it is now
possible to monitor the flow and thus determine the optimum flow for various situations. This will be a
graphic presentation of interaction of pressure, flow, and nozzles.
E) Calibration of Vehicle Mounted Flow Meters
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Connect the Portable Flow and Pressure Meter
flow tube to the pump suction port.
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Lay a 2.5î (65mm) hose from the discharge to
be tested to the portable flowmeter tube making sure there is no kink in the hose going into the
portable tube.
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With the pump engaged open the discharge gate slowly all the way.
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Control the flow with the suction port valve and by changing the RPM if needed.
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Read the displayed flow on the flow meter.
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Have an assistant calibrate the flow meter on the vehicle until the readings match. Refer to
the vehicle flow meter manufacturer's instructions to determine how to calibrate the
vehicle mounted flow meter.
FLOWMETER FACTS
Restrictions in the pipe or hose leading to the intake of the flow tube may cause erroneous readings.
If there is such a restriction, use a short length of hose (perhaps a 10 foot (3m) section) upstream of the
flow tube with a diameter equal to the diameter of the flow tube in question. Typical restrictions are
valves with an actual throat of less than the flow tube's I.D., valves partially opened, check valves and
sudden pipe bends, such as bends in monitors. Any valves on the intake side of the tube should be fully
opened.
The flow sensor comes calibrated from the factory, however, sometimes recalibration may be
necessary. This can be achieved by following the instructions in the calibration section. When calibrating
flow rate, calibrate around the mid-range point or around the flow most frequently used.
POWER
When the Portable Flow and Pressure Meter is not in use, the ON/OFF switch should be left in the
OFF position. It is powered by a rechargeable battery and therefore must be charged regularly. A fully
charged battery will provide approximately 6 hours of operating time. The Battery Low Indicator will
illuminate when the battery needs to be charged.
Charging the Battery
A 120 (240) VAC charger is mounted inside the tester. The charging cord can be stored in the
bottom cutout. To charge the internal battery connect the AC charger/power cable to the AC power input
on the front plate and to a 120 (240) VAC source.
The tester must be charged with the ìON/OFFî switch in the OFF position.
The tester will operate while connected to the battery charger.
NOTE: If the battery has not been charged for a long time, recharge for six hours.
If the battery runs down during a flow test and a 120 (240) VAC supply is not handy, you may provide
power to the tester directly from an available 12 (24) VDC battery on a vehicle. To power the tester from
a DC source, connect the optional 12 (24) VDC power cable, part number IPF-C12V, to the DC power
input on the front plate and to a 12 (24) VDC source.
Changing the Battery
Your 3.4 Ah 12 VDC internal battery should last a very long time, perhaps as long as 3 to 4 years
depending on use. To access the battery, remove the four retaining screws on the bottom of the Pelican
case. Open the cover and remove the display plate. The battery is attached to the back of the faceplate
by two more screws. The battery will have two clearly marked terminals.
SELECTING THE FLOW TUBE (If
already programmed for multi-tubes.)
NOTE: If your tester is programmed for only one tube (most testers are), then you can skip this page for
now, and proceed directly to either the "Programming a new flow tube size" page or the "Calibration"
page.
The INSIGHT Portable Flow and Pressure Meter can be calibrated for use with multiple flow tubes.
This means that you can use the same display with more than one size flow tube. The portable tester
allows you to store the flow calibration data for up to 6 flow tubes.
NOTE: If more than one flow tube has been programmed, the display
window will flash the current default flow tube selection for 3 seconds at power up. If you have multiple tubes programmed, the default
might be the 2.5" tube, in which case the display will show: (A 2.5). After that, the meter will switch to show a single "0" GPM (LPM) and
will be ready for use.
SELECTING A DIFFERENT TUBE
At any time, you can check the currently selected flow tube by pressing the MODE button. If more than 1 flow tube is programmed
into the system, pressing the MODE button again will display the next selection.
To select to use a different tube, push MODE until you see the tube you want to use shown in the display. To
ACCEPT the selection, press and hold the MODE button until the pipe size selection shown
in the window starts to flash. Release the MODE button.
PROGRAMMING A NEW FLOW TUBE SIZE
The INSIGHT Portable Flow and Pressure Meter is programmed at the factory for the tube sizes
with which it shipped. Programming the tester is done by entering a "code" which will allow you to
change the desired parameter.
CODE 312
Enter the Code
Press and hold the 'MODE' button for 5 seconds until the display shows '----'. Now you are able to enter the code.
Be quick! Code entry times out in 2 seconds!
a. Press the MODE button 3 times until the first left hand digit reads: '3'
b. Press the P button 1 time until the next digit reads: '1'
c. Press the MODE button 2 times. The last digit reads: '2'
NOTE: If a wrong code is entered, do not panic. The display will show 'E202' to
alert wrong code entry and will allow new code entry.
After successfully entering the code, the display will show the default tube
selection. (For example, if you have a 2.5" flow tube the display will show: A 2.5)
You are now ready to enter a new tube size.
Adding a New Tube Size
As an example, lets say we would like to set up a second 1.5" flow tube. You
will notice that the "A" in the display is flashing. "A" means this is the default flow
tube, B through F are additional slots that you can program. Unused slots are
set to "0.0".
The flashing digit is the "active" digit and can be changed. Press the MODE
button to change the "A" to a "b". You can use the P button to move the active
(flashing) digit around to change other numbers.
Step1 Use the MODE button to move to the first '0'.
Step 2 Use the P button to advance the number to '5'.
Step 3 Use the MODE button again to move the cursor to the second '0'.
Step 4 Use the P button to advance the number to '1'.
If another flow tube is to be programmed:
- Use the MODE button to move the cursor to the letter 'b'.
- Use the P button to advance to the letter 'C'.
Repeat Step 1 to Step 4 again.
Accept the Entry
Press and hold the MODE button follow by the P button for 3 seconds to accept the entry.
CALIBRATION
It is recommended that the calibration of the meter be checked once annually or if the operator feels
that the reading might be erroneous. Before proceeding with the calibration, clean the flow sensor with
clean water and make sure the paddlewheel spins freely.
ALWAYS FULLY CHARGE THE BATTERY BEFORE CALIBRATION
In order to calibrate the Portable Flow and Pressure meter, the following additional items will be
needed. A pitot gauge with its integral pressure gauge, a 2" (50mm) nozzle (or smaller size if 2" is not
available) and a discharge table for that nozzle. A quarter turn ball valve that can be attached to the
discharge of the flow tube. A length of hose that will be used to feed the flow tube and a pumper to
provide the water supply.
Calibration of the Portable Flow and Pressure Meter requires two persons. To calibrate the flow display, attach a 2.0" (50mm) nozzle at the end of the ball
valve. Secure the unit carefully so that the reaction force will not set it free. Open
the discharge valve on the pumper fully. Raise the pressure to around 100
PSI. Open the ball valve fully. Use the pitot tube to measure the water pressure after
the nozzle. Convert the nozzle tip pressure reading to a flow reading using a
standard discharge table (or one appropriate for the nozzle you are using).
CODE 321
Enter the Code
Press and hold the 'MODE' button for 5 seconds until the display shows '----'. Now you are able to enter the code.
Be quick! Code entry times out in 2 seconds!
a. Press the MODE button 3 times until the first left hand digit reads: '3'
b. Press the P button 2 times until the next digit reads: '2'
c. Press the MODE button 2 times. The last digit reads: '1' .
NOTE: If a wrong code is entered, do not panic. The display will show 'E202' to
alert wrong code entry and will allow new code entry.
After successfully entering the code, the display will show the default tube
selection. (For example, if you have 2.5" flow tube the display will show A 2.5). If
this is not the pipe size that needs to be calibrated, press the P button for the
next selection as described on the page "Selecting the Flow Tube". If you do not
see the tube you need, you may have to program it. See the page "Programming
a new Flow Tube Size" for instructions.
 
Once the desired tube is selected, Accept the selection: press and
hold the MODE button, and then the P button. Continue to hold them both in for 3 seconds. Release both buttons when the display shows "0".
Once you have accepted the desired flow tube size for calibration, the tester will enter calibration mode. A flashing '0' flow will appear in the
display window representing 0 GPM (LPM).
To calibrate, adjust the display until it matches a known flow. Normally this is obtained with another calibrated flow meter, a pitot gauge used in
conjunction with a straight bore nozzle of known diameter with reference to a
pressure/flow chart, or the careful observation of water filling a calibrated tank over time.
As an example, lets say we have checked the flow against a calibrated pitot gauge and determined the actual flow to be 375 GPM. We need to
change the displayed GPM reading to match that figure. Use the P button to advance the singles digit until it reads '5'. The
number will increment from 0-9 and wrap around again. Use the MODE button to move the cursor to the next number. Now the second right hand
digit '0' will flash. Again use the P button to change the number to '7'. Use
the MODE button to move the cursor to the next number. Use the P button to change the number to '3'. Now the flow reading on the display
matches the actual flow measured.
To Accept the selection, press and hold the MODE button, and (while
keeping the MODE button pressed), press and hold the P button until the display shows '----' again. The display will automatically time out in 5
seconds if no other code entry is detected.
MULTIPLE FLOW POINT CALIBRATION
For most uses, a simple single point calibration, as described on the previous pages is good
enough.
Flow Linearizer
The Portable Flow and Pressure Meter is capable of calibrating at multiple flow points and storing
those calibrations in memory. Under some conditions, this flow calibration feature can help to linearize
the flow and provide a more accurate flow reading.
A maximum of 5 flow points are allowed.
Code 322
NOTE: It is not an easy task to determine at which points the flow is nonlinear. An easy solution is to
figure out what are the flows that this discharge will most likely flow based on the types of nozzles and
nozzle sizes. Use those flow points as your calibration points. A maximum of 5 flow points are allowed.
For illustration purpose, these 5 points will be used: 100, 125, 150, 200, 250.
Step 1 Press MODE and hold it for 5 seconds to get into the programming mode. Release the
MODE button when ---- is displayed on the window.
Step 2 Enter code 322 by pressing MODE 3 times, P 2 times, and then MODE 2 times. The
window will show 322 and then display the pipe size selection. Use the P button to select the
desired pipe size. Accept the desired pipe size by pressing and holding in the MODE button and
then the P button for 3 seconds. Pt1 will appear in the display. This means you are ready to
calibrate the first point.
Step 3 Gate the discharge and use a precalibrated water flow test kit to obtain 100 GPM
(LPM).
Step 4 Press the MODE button to display the flow. The display window will show 0 to indicate that
the first point has not been calibrated yet. Use the P button to change the number. Use the
MODE button to select the number that needs to be changed. The number that is selected will
flash. When changing the number, the number will go from 0-9 and then start from 0 again. Make
sure the number ë100í shows on the display. Press and hold MODE and then, without letting go,
press P momentarily to advance to the next calibration point. The display will now show
Pt2 to
indicate calibration point number 2.
(WARNING: Release both buttons when ëPt2í shows on the display. Continuing to hold both
buttons will exit the calibration process.)
Step 5 Gate the discharge to get 125 GPM (LPM). Repeat Step 4.
Step 6 Gate the discharge for each flow rate and repeat Step 4 until all points are calibrated.
Step 7 After all the flow points have been calibrated, press and hold the MODE button and then, at
the same time, press and hold the P button for 3 seconds to exit.
NOTE: When two calibration points are too close to each other; i.e.: the difference between the current and
previous flow is less than 5%, the tester will not accept the calibration point. A code ëE206í will appear and the
tester will not allow you to advance to the next calibration point. You have to select a different calibration point
and continue with the calibration process.
HIGH FLOW WARNING
Each Portable Flow and Pressure Meter can be set up to warn the operator if too much water is flowing. This can also be used to indicate that the hose might be burst. When the alarm is active in pressure display mode the pressure mode will be disabled and the display will alternately flash the flow
rate and the warning 'HI'.
Code 315
Step 1 Press MODE and hold it for 5 seconds to get into the programming mode. Release the
MODE button when ---- is displayed.
Step 2 Enter code 315 by pressing MODE 3 times, P once, and then MODE 5 times again. The
display will show '315' and then show '0' to indicate that the high flow warning is disabled.
Step 3 Set the flow warning level, e.g: 400 GPM on a 2.5î pipe. Use the P button to change the
number. Use the MODE button to select the number that needs to be changed. The number that
is selected will flash. When changing the number, the number will go from 0-9 and then start from
0 again.
Step 4 After the flow has been set to the correct number, press and hold the MODE button and then
the P button for 3 seconds to exit.
NOTE: To disable the warning, set all the numbers to zero.
LOW FLOW WARNING
Each Portable Flow and Pressure Meter can also be set up to warn the operator if not enough water
is flowing. This can be used to indicate that the hose might be kinked, the elevation of the hose and
nozzle changed, or higher pressure is needed. When the alarm is active in pressure display mode the
pressure mode will be disabled and the display will alternately flash the flow rate and the warning 'LO'.
Code 316
Step 1 Press MODE and hold it for 5 seconds to get into the programming mode. Release the
MODE button when ---- is displayed.
Step 2 Enter code 316 by pressing MODE 3 times, P once, and then MODE 6 times again. The
display will show '316' and then show ë0í to indicate that the low flow warning is disabled.
Step 3 Set the flow warning level, e.g: 90 GPM on a 2.5î pipe. Use the P button to change the
number. Use the MODE button to select the number that needs to be changed. The number that
is selected will flash. When changing the number, the number will go from 0-9 and then start from
0 again.
Step 4 After the flow has been set to the correct number, press and hold the MODE button and then
the P button for 3 seconds to exit.
NOTE: To disable the warning, set all the number to zero.
FLOW TUBE
ORIENTING THE FLOW TUBE
Always orientate the flow tube in your hose arrangement so that the flow sensor is located downstream
of the flow.
NOTE: The location of the pressure sensor may vary.
REMOVING THE FLOW SENSOR
In the event that the paddle wheel flow sensor becomes clogged with mud and grass, simply
remove the retaining nut and slide the sensor out. It may be cleaned with soap and water.
RE-INSTALLING THE FLOW SENSOR
Some units have a flat alignment tab on the sensor housing that matches the flat of the paddle wheel
to correctly align the flow sensor with the direction of flow. For units without this tab on the sensor
housing, align the flat tab on the paddle wheel to face the female swivel end of the tube. Visual alignment
wire loop should be aligned with water flow direction. Install and HAND tighten the retaining nut.
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