An ideal flow meter would measure any liquid in any size pipe. The accuracy would be perfect and the meter would be able to measure flows ranging from 0 gallons/min up to infinity. However, we don't live in an ideal world and flow meters are no exception!! In order to properly chose and install the meter correctly, some education is needed.
HOW DO PADDLEWHEEL FLOWMETERS WORK?
Our paddlewheel flowmeters consist of two major components; the pipe adapter and the paddlewheel sensor. The paddlewheel sensor is designed to be inserted into any of the adapters. Liquid flowing in the pipe causes the paddlewheel to spin at a rate linearly proportional to the flowrate. Magnets, contained in the paddle, rotate past a switch, pulses from the switch are processed by the microprocessor and then displayed as a flowrate on the LCD display.
WHAT ARE PIPE ADAPTERS??
Adapters allow the same meter head to be mounted to the various sizes and schedules of pipe. The same meter head can be programmed for the different pipes. Adapers come in two different varieties.
* Pipe Mounted- The fitting for the meter is solvent welded to a 13" section of pipe. Pipes sizes range from 1/2" to 4".
*Insertion Adapter - Saddle style fittings are designed to mount directly on your existing pipe.
The saddle is installed by clamping the saddle onto and then drilling an 1 1/2" hole in the pipe. Cutting the pipe is not necessary. Saddles are available for Schedule 40 & 80 pipe, in addition we can machine adapters for specific applications.
PADDLEWHEEL SENSORS(meter heads) – The Paddlewheel sensors are all the same. They are field programmable for the different pipes and schedules.
CHOOSING THE CORRECT PIPE ADAPTER
The flow rate must be within the
recommended range for the flowmeter to function properly.
Inadequate flow velocity in large pipes is the number one reason flow
meters don't operate as expected. An adequate flow not only reliably
spins the
paddle, it also washes silt and air bubbles out of the pipe. If
the flow rate is at or below the minimum recommended rate, neck down to
a smaller diameter pipe.
If you are ordering an insertion style adapter for your existing plumbing, it must be for your exact pipe. The adpaters are machined to fit the outer diameter of the pipe and also compensate for pipe wall thickness differences. Therefore, if you mount an adpater for a schedule 40 pipe on a schedule 80 pipe, the meter will produce very inaccurate results. We can custom machine adapters as long as the pipe has a smooth outer surface.
In the 1/2", 3/4" and 1" models the adapters are only offered in schedule 80 pipe sections. Schedule 40 fittings and pipe will glue directly to schedule 80 pipe, the pipes have the same outside diameter.
For pipe sizes 2" and smaller, most people purchase the pipe section adapter as they are easier to install. However, with 3" and larger pipes, splicing in a section of pipe becomes more diffucult and the insertion mounted adapters are desirable. The six and eight inches meters are only offered in the insertion mounted style.
If you are ordering an insertion style adapter for your existing plumbing, it must be for your exact pipe. The adpaters are machined to fit the outer diameter of the pipe and also compensate for pipe wall thickness differences. Therefore, if you mount an adpater for a schedule 40 pipe on a schedule 80 pipe, the meter will produce very inaccurate results. We can custom machine adapters as long as the pipe has a smooth outer surface.
In the 1/2", 3/4" and 1" models the adapters are only offered in schedule 80 pipe sections. Schedule 40 fittings and pipe will glue directly to schedule 80 pipe, the pipes have the same outside diameter.
For pipe sizes 2" and smaller, most people purchase the pipe section adapter as they are easier to install. However, with 3" and larger pipes, splicing in a section of pipe becomes more diffucult and the insertion mounted adapters are desirable. The six and eight inches meters are only offered in the insertion mounted style.
INSTALLATION NOTES
The accuracy is based on steady, undisturbed flow with a fully developed turbulent flow. Swirling and other disruptions in the flow will effect the meter’s accuracy. Uniform developed flow is produced in straight runs of pipe.
The meter must be installed in a straight length of pipe with at least 10 pipe diameters upstream of the meter. The length of pipe downstream must be at least 5 pipe diameters. Major flow obstructions, such as gate valves, pumps and multiple elbows will require longer straight runs of pipe before the meter.
Back pressure is needed on downward flows to assure the pipe remains full of water.
PART NUMBERS
All complete meters begin with PT (Paddle wheel meter withTotalizer)
Next digit Indicates either a pipe mounted adapter(P) or adapter made to be installed on your existing pipe(I).
Third is the schedule of pipe, either schedule 40 or 80.
Last digits are the pipe size(0.5, 0.75, 1.0, 1.5, 2.0, 3.0, 4.0, 6.0, 8.0).
Example
PT-P-40-2.0
Indicated a 2" Schedule 40 meter mounted on a 13" pipe section.
Complete Meters
Pipe Mounted meters(adapters supplied with a 13" section of pipe)
Complete Meters
Insertion style meters(adapters strap to your existing pipe)
| PT-I-80-2.0 |
2" sch 80 meter to be mounted on your existing pipe |
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| PT-I-40-2.0 |
2" sch 40 meter to be mounted on your existing pipe |
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| PT-I-80-3.0 |
3" sch 80 meter to be mounted on your existing pipe |
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| PT-I-40-3.0 |
3" sch 40 meter to be mounted on your existing pipe |
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| PT-I-80-4.0 |
4" sch 80 meter to be mounted on your existing pipe |
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| PT-I-40-4.0 |
4" sch 40 meter to be mounted on your existing pipe |
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| PT-I-80-6.0 |
6" sch 80 meter to be mounted on your existing pipe |
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| PT-I-40-6.0 |
6" sch 40 meter to be mounted on your existing pipe |
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| PT-I-80-8.0 |
8" sch 80 meter to be mounted on your existing pipe |
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| PT-I-40-8.0 |
8" sch 40 meter to be mounted on your existing pipe |
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