TRAINING BULLETIN APPARATUS P-2 January 22, 1998 FLOWMETERS

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1 TRAINING BULLETIN APPARATUS P-2 January 22, 1998 FLOWMETERS 1. INTRODUCTION 1.1 The intention of this bulletin is to describe the operation and calibration of the SPAN FLOWMINDER, the flowmeter presently in use. 1.2 Flowmeters provide added safety. With pressure gauges, pressure at the end of the line where firefighters need it, differs from pressure at the beginning of the line where it is measured. Pressure is reduced because of friction loss, head pressure, etc., and complicated formulas must be used to determine the water flow at the nozzle. Flowmeters measure flow in gallons per minute (GPM), which is the same at the beginning and the end of a hose line. As water is not compressible, what the display shows at the pumper is what the firefighters are receiving at the nozzle. This enables the motor pump operator to know the volume of water (in GPM) that is being delivered to the nozzle. 1.3 Flowmeters can be used with any type of nozzle to show the water flow. This is especially important with the Automatic Fog Tip (FT-2) to insure adequate water for fire extinguishment and firefighter safety. 1.4 These meters can also provide the total amount of water used with the totalizer feature. (Refer to Section 6). 2. EQUIPMENT AND SCHEDULE 2.1 Divisions will be issued a test kit consisting of a pitot gauge, a set of pitot nozzles, and a stream shaper for use during calibration. 2.2 Units shall calibrate their flowmeters semi-annually and/or when necessary to insure proper working order. 1

2 3. CALIBRATING THE FLOWMETER 3.1 Calibration is setting the electronics in a flowmeter to match the water flow in a pipe (as measured in psi by a pitot gauge). Flow is determined by the size of the pipe, the velocity in the pipe, and the size of the nozzle. 3.2 Zeroing sets the zero point with no flow. Calibrating sets a setpoint in the middle range of the flow. A low checkpoint and a high checkpoint are also used during calibration. 3.3 The Discharge Table For Water-Flow Test Kit-Style 9015 lists the suggested setpoints (in psi and GPM) for various pressures and pitot nozzles sizes. The following step-by-step instructions explain how to zero and calibrate the flowmeter. 4. ZEROING THE DISPLAY 4.1 Each time you calibrate a flowmeter, you should zero the display using the following procedure: Connect the pumper to a hydrant using an inlet on the side of the apparatus opposite the control panel Connect the stream shaper to the discharge gate to be tested Connect the test kit body swivel to the stream shaper and rotate the pitot blade out of stream position Open the By-Pass cooler on the pump panel, run a short 20 to 30 second spurt of water at full flow, and then shut the water off Remove the cover screw labeled S Push the SET bottom. If the display reads other than 0 while holding the SET button, insert a small screwdriver into the S hole to turn the potentiometer. If the display shows -0, or a negative number, turn clockwise until the minus sign barely turns off, leaving 0. Turn the potentiometer slowly; it takes a few seconds for the display to change and it is easy to turn it too far. If the display shows a positive number, turn the potentiometer counterclockwise until you see -0. Then slowly turn the potentiometer clockwise until the minus sign barely turns off, leaving 0.

3 January 22, 1998 T.B. APPARATUS P-2 FLOWMETERS If the flowmeter display can not be zeroed, notify The Division of Fleet Maintenance Reinstall the S cover screw, checking to be sure the O-ring is under the screw. The display is now set at zero. 5. PROCEDURE FOR CALIBRATING SPAN FLOWMETERS WITH A 2 1/2 INCH DISCHARGE USING THE AKRON WATER FLOW TEST KIT 5.1 TEST NUMBER SETPOINT # Install the 1 1/8 inch test barrel into the pitot test gauge assembly and secure the retaining lock nut Rotate pitot blade into center steam position and tighten thumbscrews Fully open the discharge gate that you are checking and obtain a reading of 50 psi on the pitot gauge by increasing or decreasing the fire pump panel throttle control (or closing the discharge gate if necessary). The flowmeters display should read 260 gpm. If it does not read 260 gpm go to Section Remove the cover screw labeled F on the flowmeters display. If the display reads a higher number, turn the set screw counterclockwise to obtain 260 gpm reading on the display gauge. If the display reads a lower number, turn the set screw clockwise to obtain 260 gpm reading on the display gauge When pumper must continue to operate (e.g. endurance test), rotate blade out of stream position to reduce wear and avoid damage. 5.2 TEST NUMBER SETPOINT # Install the 1 1/4 inch test barrel into the pitot test gauge assembly and secure the retaining lock nut Rotate pitot blade into center stream position and tighten thumbscrews Operate the Fire Pump in the normal safe manner. Fully open the discharge gate that you are checking and obtain a reading of 50 psi on the pitot gauge by increasing or decreasing the fire pump panel throttle control, the display should read 330 gpm. If it does not read 330 gpm go to Section

4 If the display reads a higher number, turn the setscrew counterclockwise to obtain 330 gpm reading on the display gauge. If the display reads a lower number, turn the set screw clockwise to obtain 330 gpm reading on the display gauge Reinstall the cover screw labeled F. NOTES: 1. As the flowmeter s last digit is designed to stay at 0, set GPM in ten digit increments such as 230, 240, 250, etc. 2. Decrease the number below the desired GPM then make small adjustments clockwise until you reach the desired reading. 3. Flowmeter readings should be within approximately 3% of maximum flow. Example: When the pitot shows 50 psi (l 1/8 inch tip), the flowmeter should read 260. It can read between 250 and 270 and be within the allowable range, which is 3% of the maximum flow. 4. If the flowmeter can not be calibrated for any reason (i.e.: display lights missing) or it becomes obvious the calibration will not hold, The Division of Fleet Maintenance should be notified. 6. TOTALIZER 6.1 The Totalizer feature allows you to check the total flow from each discharge at any time. To know how many total gallons of water have been pumped since the unit was cleared, do the following: Push and hold the TOTAL button located on the flowmeters front panel; a number is displayed Multiply the number by 100 for the total gallons of water pumped since the flowmeter was reset or turned on. For example, if 23 is shown, 2300 gallons have been pumped on that line. 6.2 Anytime the batteries are turned off the Totalizer automatically resets to zero.

5 January 22, 1998 T.B. APPARATUS P-2 FLOWMETERS SAFETY FIRST AND HELPFUL TIPS 1. When pumping always make certain that the maxi brake is on and you have chocked the rear wheels. 2. Cap all discharge gates that are not in use at the time of this test. 3. Make certain that you are in pumps and the green O.K. to pump light is on. 4. Never operate the fire pump without flowing water (open a drain valve). 5. Extreme caution must be used when calibrating flowmeters while the stream of water is flowing. 6. When adjusting the setscrew on the flowmeter, make slow 1/8 turns and pause to check the display reading. Potentiometers are located beneath the cover screws marked S and F. After using the potentiometers for calibrating, make certain the cover screws and O-rings are in place to keep water out of the interior. 5

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