Flow Meter Specification

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FLOW METER SPECIFICATIONS

FLOW METER

SPECIFICATIONS
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FLOW METER SPECIFICATIONS
FLOW METER
OPERATION
The Calsense Flow Meter consists of an impeller and a sensing device, which measures the flow in gallons per minute (GPM). The irrigation controller learns an average GPM value for each station. If a broken head or riser causes the flow to exceed the learned flow rate by a selected percent, the irrigation controller shuts off that station automatically and advances to the next station. When irrigation has finished, the controller marks that one station with a HIGHFLOW alert on the display. During the next irrigation, that station will again come on and a measurement will be taken, if the flow still exceeds the learned average flow for that station, the controller instantly turns it off and again displays a HIGHFLOW alert.
Calsense Irrigation Controllers monitor the flow meter continuously and will close a master valve if at any time the flow exceeds the user selected Mainline break number. A Flashing MAINLINE BREAK alert on the irrigation controller will alert the user to the problem. A normally closed or normally open master valve can be used. No irrigation will occur until the MAINLINE BREAK alert is cleared by the user.
If a valve does not open, or has a measured flow rate below the flow meter minimum, the irrigation controller will flash a NO FLOW alert on the display.
If the backflow preventer or water meter has been turned off, every station on the controller will have a NO FLOW alert.
RESTRICTIONS
Certain hydraulic restrictions should be considered when designing an irrigation system with the Calsense Flow Meter. Since the irrigation controller independently learns station flow rates, the flow meter must be installed in a pipe through which only the water regulated by the irrigation controller flows. Therefore there must be isolated supply lines for each controller.
If a loop system exists or if several irrigation controllers are fed off of one main line, the –FL option should be recommended.

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AVAILABLE FLOW METER SIZES AND MODEL NUMBERS
Calsense Flow Meter sizes and model numbers:

SIZE

MODEL NUMBER

1” brass Tee 1-1/4” Brass Tee 1-1/2” Brass Tee 1-1/2” Sch 80 PVC Tee 2” Sch 80 PVC Tee 2” Brass Tee 3” Sch 80 PVC Tee 4” thru 18”

FM-1B FM -1.25B FM- 1.5B FM- 1.5 FM-2 FM-2B FM-3 FMBX (Saddle Mounted)

SIZE DETERMINATION FACTORS
The correct flow meter size to use is NOT determined by the size of the irrigation mainline, but based on station flow rates. Selection of flow meter size depends on three factors.
• Maximum GPM flow rate for system. • Minimum GPM flow rate for the system. • Permissible pressure loss through the flow
meter.
The maximum GPM is the full scale reading of a flow meter, this must not be exceeded by the flow rate of any station on an irrigation system. The minimum GPM is the lowest flow rate at which a flow meter will read water flow. If the flow rate of a station does not exceed this minimum, a NO FLOW alert will be generated whenever irrigation occurs.
To determine the correct flow meter size when designing an irrigation system, first determine the station with the highest flow rate on the system, next determine the station with the lowest flow rate on the system, then make sure that both flow rates are within the operating range of the selected flow meter size in the chart.

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SIZING CHART:

FLOW METER SPECIFICATIONS

Model
FM-1B FM-1.25B FM-1.5B

Min Flow (.5 fps)
2 gpm 3 gpm 4 gpm

Recommended Range

Min Flow

Max Flow

(1 fps)

(15 fps)

3 gpm

50 gpm

5 gpm

81 gpm

7 gpm

105 gpm

Max Flow (15 fps)
50 gpm 81 gpm 106 gpm

PSI Loss @ gpm
0.5 PSI @ 36 gpm 0.5 PSI @ 69 gpm 0.5 PSI @ 96 gpm

Model
FM-1.5 FM-2 FM-2B FM-3

Min Flow (.5 fps)
4 gpm 6 gpm 6 gpm 12 gpm

Recommended Range

Min Flow

Max Flow

(1 fps)

(15 fps)

7 gpm

105 gpm

11 gpm

166 gpm

11 gpm

166 gpm

24 gpm

363 gpm

Max Flow (30 fps)
212 gpm 333 gpm 333 gpm 727 gpm

PSI Loss @ gpm
0.5 PSI @ 96 gpm 0.5 PSI @ 165 gpm 0.5 PSI @ 165 gpm 0.5 PSI @ 390 gpm

Model FMBX

Min Flow (.5 fps)
.5 fps

Recommended Range

Min Flow (1 fps)

Max Flow (15 fps)

1 fps

15 fps

Max Flow (30 fps)

PSI Loss @ gpm

30 fps

N/A

(Flows based on CL 200 SDR 21 PVC pipe)

TECHNICAL SPECIFICATIONS:
Parameters: FM-1B, FM-1.25B, FM-1.5B

Body Construction:

Accuracy: Linearity: Repeatability: Flow Range: Max Pressure:

+/- 1% of full scale +/- 0.7% +/- 0.7% 0.5 to 15 feet/second 400 PSI @ 150F (65.5 C)

Parameters: FM-2B

Accuracy: Linearity: Repeatability: Flow Range: Max Pressure:

+/- 1% of full scale +/- 1% +/- 1% 1 to 30 feet/second 200 PSI @ 150F (65.5 C)

FM-B series: FM series:

all bronze Schedule 80 PVC

Parameters: FM-1.5, FM-2, FM-3

Accuracy: Linearity: Repeatability: Flow Range: Max Pressure:

+/- 1% of full scale +/- 0.5% +/- 0.5% 1 to 30 feet/second 100 PSI @ 68F (20 C)

Insert Construction:

Impeller: Bearing:
Shaft: Housing:
O-rings:

Glass reinforced nylon Ultrahigh molecular Weight polyethylene Tungsten Carbide Glass reinforced Polyphenylene sulfide Ethylene propylene

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FLOW METER SPECIFICATIONS
PERMISSIBLE PRESSURE LOSS
The permissible pressure loss is important because there is pressure loss through the flow meter, through the pipe upstream of the flow meter and downstream of the flow meter. This pipe must be the same diameter as the flow meter to keep turbulence to a minimum. The length required upstream of the flow meter is ten times the flow meter size. The

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length required downstream of the flow meter is five times the flow meter size. The table below provides pressure losses for several flow meters with appropriate pipe extensions.

Pressure Loss in Pounds Per Square Inch at Various Flow Rates

FM-1B FM-1.25B

10 GPM .046 .014

20 GPM .166 .050

30 GPM .351 .106

40

50

60

70

80

GPM GPM GPM GPM GPM

.597 .902 ---- ---- ----

.181 .274 .283 .510 .653

(Based on CL200 SDR21 PVC Pipe)

FM-1.5B FM-2B FM-1.5 FM-2 FM-3

40 GPM .097 .036 .097 .036 .007

60 GPM .206 .076 .206 .076 .016

100 GPM .530 .196 .530 .196 .040

160 220 280 340 400 GPM GPM GPM GPM GPM ---- ---- ---- ---- ---.468 ---- ---- ---- ------- ---- ---- ---- ---.468 ---- ---- ---- ---.096 .0173 .270 .387 .522
(Based on CL200 SDR21 PVC Pipe)

MINIMUM FLOW METER RATES
The minimum GPM is important because this determines the minimum rate at which the flow meter impeller turns. If the impeller turns too slowly the flow meter reading will not be accurate.

MINIMUM FLOW RATES FOR CALSENSE

FLOW METERS

FLOW METER

MINIMUM FLOW

PART NUMBER

RATE (1 fps)

FM-1B

3 GPM

FM-1.25B

5 GPM

FM-1.5

7 GPM

FM-1.5B

7 GPM

FM2

11 GPM

FM-2B

11 GPM

FM-3

24 GPM

(Based on CL200 SDR21 PVC Pipe)

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MAXIMUM FLOW METER RATES
The maximum GPM is important because the flow meter full scale reading exceeding the maximum flow rate will lead to premature flow meter failure due to excessive wear.
MAXIMUM FLOW METER PRESSURE
It is important not to exceed the maximum recommended pressure rating of a flow meter. The flow meter body may be damaged and warranty is voided. If necessary a pressure regulator should be placed in the irrigation mainline, upstream of the flow meter. The following table provides the maximum recommended pressure rating for each size flow meter.

FLOW METER SPECIFICATIONS

MAXIMUM FLOW RATES FOR CALSENSE

FLOW METERS

FLOW METER

MAXIMUM FLOW

PART NUMBER

RATE (15 fps)

FM-1B

50 GPM

FM-1.25B

81 GPM

FM-1.5

105 GPM

FM-1.5B

105 GPM

FM2

166 GPM

FM-2B

166 GPM

FM-3

363 GPM

(Based on CL200 SDR21 PVC Pipe)

MAXIMUM FLOW METER PRESSURE

RATINGS

FLOW METER

MAXIMUM

PART NUMBER

PRESSURE

FM-1B

400 PSI

FM-1.25B

400 PSI

FM-1.5B

400 PSI

FM2B

200 PSI

FM-1.5

100 PSI

FM-2

100 PSI

(Based on CL200 SDR21 PVC Pipe)

PHYSICAL SPECIFICATION
The flow meter is installed after the water meter or backflow device. The Master Valve can be installed on either side of the flow meter. The mainline pipe is usually sized down during the installation to accommodate the fitting of the flow meter. Note the intended direction of the flow as indicated by an arrow on the top of the flow meter. There must be free, unrestricted pipe of the same diameter as the flow meter, with a length of 10 times the flow meter size upstream, and 5 times the flow meter size downstream of the flow meter tee. This should apply to distance from any valve, fitting, meter, or backflow device.

• The flow meter shall be easily accessible, housed in a rectangular valve box, and marked ‘FM’.
• There should be 6” to 8” of pea gravel beneath the flow meter in the valve box.
• The length of #14 AWG wire connecting the flow meter to the irrigation controller shall not exceed 2,000 feet.
See Figure 1

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FLOW METER SPECIFICATIONS
ELECTRICAL SPECIFICATION
Wires from the flow meter to the irrigation controller should consist of one (1) black and one (1) red standard #14 AWG irrigation wire. The flow meter has two wire leads, a black and a red. At the controller, the black wire in the black wire harness is connected to the black flow meter wire, and the red wire in the black wire harness is connected to the red flow meter wire.
The Calsense Flow Meter operates at 9 volts DC. The flow meter wires should be separated from other controller wires when pulled up at the irrigation controller site. If 24 VAC is used to test field wires when determining proper sequencing, and is applied to the flow meter wires, the sensing unit in the flow meter could be damaged.

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It is very important that all electrical connections are tight and dry. Any water leaking into a connection will cause flow meter problems. Additionally, there should never be any buried splices between the flow meter and the irrigation controller. Use only Calsense recommended electrical connectors.
Recommended Electrical Connectors:
• Spears DS-100 Connectors with Spears DS300 sealant.
• 3M Scotchlok No. 3570 connector sealing pack.
See Figure 2

FLOW METER INSTALLATION

FIGURE 1

MINIMUM UPSTREAM AND DOWNSTREAM DISTANCE FOR VARIOUS FLOW METER SIZES

Flow Meter Size
1.00” 1.25” 1.50” 2.00” 3.00”

Minimum Upstream Pipe Length 10.00” 12.50” 15.00” 20.00” 30.00”

Minimum Downstream Pipe Length 5.00” 6.25” 7.50” 10.00” 15.00”

Pipe Diameter
1.00” 1.25” 1.50” 2.00” 3.00”

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FLOW METER SPECIFICATIONS

MULTIPLE FLOW METER INTERFACE (-F).

All models of Calsense controllers can receive up to three separate flow meter inputs on projects consisting of more than one water source for irrigating landscape when equipped with the optional (-F) interface. The controller will sum up the readings of all flow sensors connected. The irrigation controller is specified as a (-F) controller.

The first flow meter is wired to the irrigation controller using the standard Calsense red and black flow meter wires. The second and third flow meters are wired to the irrigation controller using an additional wire harness supplied when a (-F) option is specified.
See Figure 2

CALSENSE (-F) OPTION WIRING DIAGRAM

FIGURE 2
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FLOW METER SPECIFICATIONS

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FMBX CALIBRATION
The FMBX insertion sensor uses unique K and Offset numbers for calibration. These numbers are derived from calibration runs using NIST traceable

instruments. Using both a K and an Offset number provides higher accuracy than using a K ( Pulse/ Gal) factor alone. K and Offset numbers for each tee configuration are listed in the following tables. The table on the following pages provide calibration and operation data for most scheduled pipe sizes from 3” through 18” .

FMBX DESCRIPTION OF CHART SECTION INFORMATION

SECTION 1: SECTION 2: SECTION 3: SECTION 4 AND 5:

Nominal Pipe Size. Pipe Outside Diameter defined by ASA B36.10 and other standards. Pipe Inside Diameter defined by ASA B36.10 and other standards. The K value and Offset that should be used in our frequency equation:

Example:

SECTION 6:

GPM

Freq =

- Offset

K

This equation describes the frequency of the output signal of all Calsense flow sensors. By substituting the appropriate K and Offset values from the table, the sensor’s output frequency can be calculated for each pipe size. This information is required when using the FMBX insertion sensor.

This section indicates the suggested flow range of sensors in each pipe size. Calsense sensors will operate both above and below the indicated flow rates. However, good design practice dictates the use of this range for best performance. Sensors should be sized for flow rather than pipe size. To prevent disturbances to the flow profile always connect the sensor tee to pipe nipple measuring at least 10 pipe diameters in length on the upstream (supply) side and at least 5 pipe diameters in length on the downstream (delivery) side before making the transition in pipe size.

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FLOW METER SPECIFICATIONS

Section 1

FMBX FLOW METER

CALIBRATION TABLE FOR PIPE SIZES 3” THROUGH 36”

Section2

Section 3

Section 4

Section 5

Pipe Size
3” Sch 10S Std. Wt., Sch 40 Extra Strong, Sch 80 PVC Class 125 PVC Class 160 PVC Class 200
4” Sch 10S Std. Wt.,Sch 40 Extra Strong, Sch 80 PVC Class 125 PVC Class 160 PVC Class 200
5” Sch 10S Std. Wt., Sch 40 Extra Strong, Sch 80
6” Sch 10S Std. Wt., Sch 40 Extra Strong, Sch 80 PVC Class 125 PVC Class 160 PVC Class 200
8” Sch 10S Sch 20 Sch 30
Std. Wt., Sch 40 Sch 60
Extra Strong, Sch 80 PVC Class 125 PVC Class 160 PVC Class 200 10” Sch 10S Sch 20 Sch 30 Std. Wt., Sch 40 Sch 60
Extra Strong, Sch 80 PVC Class 125 PVC Class 160 PVC Class 200

Pipe Outside Diameter
3.500” 3.5” 3.5” 3.5” 3.5” 3.5” 4.5” 4.5” 4.5” 4.5” 4.5” 4.5”
5.563” 5.50” 5.50” 6.625” 6.5” 6.5” 6.625” 6.625” 6.625” 8.625” 8.625” 8.625” 8.625” 8.625” 8.625” 8.625” 8.625” 8.625” 10.75” 10.75” 10.75” 10.75” 10.75” 10.75” 10.75” 10.75” 10.75”

Pipe Inside Diameter
3.260” 3.068” 2.900” 3.284” 3.230” 3.166” 4.260” 4.026” 3.826” 4.224” 4.154” 4.072” 5.295” 5.047” 4.813” 6.357” 6.065” 5.761” 6.217” 6.115” 5.993” 8.329” 8.125” 8.071” 7.981” 7.813” 7.625” 8.095” 7.961” 7.805” 10.420” 10.250” 10.136” 10.020” 9.750” 9.564” 10.088” 9.924” 9.728”

K value
5.009 4.362 3.858 5.094 4.902 4.682 9.597 8.34 7.354 9.396 9.013 8.578 16.305 14.674 13.165 24.089 21.574 19.457 22.853 21.968 21.068 43.914 41.653 41.063 40.086 38.288 36.315 41.324 39.869 38.203 70.195 67.668 66.069 64.532 61.016 58.644 65.431 63.272 60.733

Offset
.090 .063 .043 .093 .085 .076 .241 .229 .188 .240 .240 .239 .250 .248 .246 .260 .257 .254 .258 .257 .256 0.286 0.283 0.283 0.281 0.279 0.276 0.283 0.281 0.279 0.321 0.318 0.316 0.314 0.309 0.306 0.315 0.312 0.309

Section 6
Suggested Operating Range (GPM)
12-400 12-400 12-400 12-400 12-400 12-400 20-600 20-600 20-600 20-600 20-600 20-600 30-900 30-900 30-900 50-1,500 50-1,500 50-1,500 50-1,500 50-1,500 50-1,500 80-2,500 80-2,500 80-2,500 80-2,500 80-2,500 80-2,500 80-2,500 80-2,500 80-2,500 125-4,000 125-4,000 125,4000 125-4,000 125-4,000 125-4,000 125-4,000 125,4000 125,4000

Continued on next page

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FLOW METER SPECIFICATIONS

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Section 1

FMBX FLOW METER

CALIBRATION TABLE FOR PIPE SIZES 3” THROOUGH 36”

Section2

Section 3

Section 4

Section 5

Pipe Size
12” Sch 10S Sch 20 Sch 30
Std. Wt.,Sch 40S Sch 40 Sch 60
Extra Strong Sch 80
PVC Class 125 PVC Class 160 PVC Class 200
14” Sch 10S Sch 20
Std. Wt., Sch 30 Sch 40 Sch 60
Extra Strong Sch 80
16” Sch 10S Sch 20
Std. Wt., Sch 30 Sch 60
Extra Strong, Sch 40 Sch 80
18” Sch 10S Sch 20 Sch 30 Std. Wt. Sch 40 Sch 60
Extra Strong Sch 80
20” Std. Wt.,Sch 20 Sch 40
Extra Strong, Sch 30 Sch 80
22” Std. Wt.,Sch 20 Extra Strong, Sch 30
Sch 80

Pipe Outside Diameter
12.75” 12.75” 12.75” 12.75” 12.75” 12.75” 12.75” 12.75” 12.75” 12.75” 12.75” 14.00” 14.00” 14.00” 14.00” 14.00” 14.00” 14.00” 16.00” 16.00” 16.00” 16.00” 16.00” 16.00” 18.00” 18.00” 18.00” 18.00” 18.00” 18.00” 18.00” 18.00” 20.00” 20.00” 20.00” 20.00” 22.00” 22:00” 22.00”

Pipe Inside Diameter
12.390” 12.250” 12.090” 12.000” 11.938” 11.625” 11.750” 11.376” 11.966” 11.770” 11.538” 13.500” 13.375” 13.250” 13.124” 12.814” 13.00” 12.50” 15.500” 15.375” 15.250” 14.688” 15.000” 14.314” 17.500” 17.375” 17.124” 17.250” 16.876” 16.500” 17.000” 16.126” 19.25” 18.812” 19.000” 17.938” 21.25” 21.00” 19.75”

K value
104.636 102.553 99.347 97.576 96.369 90.441 92.775 85.922 96.912 93.152 88.842 122.307 120.216 118.151 116.096 111.148 114.098 106.299 159.243 156.742 154.267 143.456 149.394 136.548 202.739 199.828 194.061 196.943 188.464 180.171 191.25 172.152 246.179 234.836 239.666 213.14 301.975 294.642 259.513

Offset
0.367 0.364 0.36 0.358 0.356 0.348 0.351 0.342 0.357 0.352 0.346 0.391 0.388 0.385 0.382 0.376 0.33 0.369 0.44 0.436 0.433 0.419 0.427 0.41 0.498 0.494 0.486 0.49 0.479 0.469 0.482 0.457 0.555 0.540 0.547 0.511 0.621 0.616 0.573

Section 6
Suggested Operating Range (GPM)
175-5,000 175-5,000 175-5,000 175-5,000 175-5,000 175-5,000 175-5,000 175-5,000 175-5,000 175-5,000 175-5,000 200-6,000 200-6,000 200-6,000 200-6,000 200-6,000 200-6,000 200-6,000 300-9,000 300-9,000 300-9,000 300-9,000 300-9,000 300-9,000 350-10,000 350-10,000 350-10,000 350-10,000 350-10,000 350-10,000 350-10,000 350-10,000 400-12,000 400-12,000 400-12,000 400-12,000 500-15,000 500-15,000 500-15,000

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