|Plant exterior view|
Ashley Valley Water & Sewer Improvement District serves rural-county residents living outside Vernal, Utah. The water district supports a growing population of 10,000 people, as well as local ranchers and farmers raising livestock, alfalfa, hay, grains and feed corn.
The district’s water supply is derived from a year-round active spring, additionally fed by mountain snow melt. Seasonal and weather variations affect water availability from these resources, which the district shares with several other water entities. Accurate tracking of water use for allocation and conservation purposes is important.
The district’s drinking water plant is an up-flow clarifier, which according to its water allocation, can process 8 million gallons a day of raw water (Figure 1). If the plant exceeds its water-share allocation, the district is forced to purchase water at a more expensive rate.
“We installed the McCrometer FPI Mag flowmeter in our raw water line where it comes into our treatment plant,” says Ryan Goodrich, assistant manager at the district. “Accurate entry point of measurement is critical for us so we know how much water we treat, use internally and supply each day.”
The district compares the daily flow data to actual water-right share.
“The FPI Mag meter is performing very well in normal operations,” Goodrich adds, “including high-flow cycles, such as when we flush the plant’s filters. The immediate benefit of the FPI meter is its accuracy and reliability over the full range of flow rates required by our plant’s operations.”
|FPI Mag meter installed at plant raw water entry poin|
What happened was that when the need to replace an existing flowmeter occurred simultaneously with needs for improved performance in an on-going pilot plant application, the district plant operations team looked for a reliable flow-measurement solution that was easy to install, without impacting operations. It had to be high-performance, economical and with minimal maintenance requirements. The district wanted to minimize operational interruptions and avoid requirements for extra personnel when bringing flowmeters into service.
The district staff contacted the applications team at McCrometer. It recommended the FPI Mag flowmeter due to its consistent accurate performance and easy hot-tap installation, low maintenance and versatility.
Installation at the point of entry to the plant was simple: an 18-inch main-line pipe was tapped and an FPI Mag meter with a saddle-mount and transmitter was installed. Since the previous meter had already been wired, it was easy to connect the transmitter.
“We deal with many different types of meters and applications where the meter display needs to be calibrated, which takes extra time and can be confusing,” says Goodrich. “I’m pleased that we could install the FPI Mag so quickly, and the display right away made it easy to see it was working.”
Adding the meter to the plant SCADA system was simple. “The instructions were clear. As soon as the connection was made, the meter showed up immediately on the SCADA system,” Goodrich says.
The district staff made a few adjustments to its SCADA program, and the meter was fully operational within the system. With no programming necessary, there was no need to hire a programmer and spend extra money to bring the meter online. Goodrich said, “That extra cost for programming can be a real problem in some cases and will actually prevent us from using some meters.”
More demand denouement
|FPI Mag flow sensor cut-away view|
The FPI Mag meter has been installed at the plant for about seven months with no maintenance needs. “It is simple to pull and clean when necessary,” Goodrich says.
Goodrich noted there was a burst pipe incident at the plant, which soaked the instruments and automation equipment. The staff had to turn off the power to fix the problem. When the power was turned back on, the FPI Mag meter and its transmitter came right back online without the need to reset parameters or make additional adjustments.
The district’s need for accurate measurement to ensure compliance with its water-right share is met by the FPI Mag flowmeter’s next-generation design, says McCrometer. Its advanced sensor features multiple coils and electrodes inserted in a tube assembly inserted completely into the pipe, to measure the full profile of the flow stream, providing exceptional accuracy even in challenging flow conditions (Figure 3).
A filtering algorithm in the meter’s signal converter supports accuracy of plus-or-minus 0.5 percent of reading from 1 to 32 ft./sec. and plus-or-minus 1.0 percent from 0.3 to 1 ft./sec. The signal converter also includes: built-in dual 4-20 mA outputs for communication flexibility, additional programmable outputs to support SCADA systems and a simplified menu structure for ease of use and, as mentioned, precluding the need for programming assistance from outside contractors.
The district is pleased with the accuracy and performance of the FPI Mag meter. “The flowmeter has performed as well as advertised and the install process was as easy as we were told. We have been very impressed with the whole process, from ordering to installation,” says Goodrich
Based on the successful results of the FPI Mag in the pilot-plant application, the district is considering the purchase of additional meters for a new treatment facility. Goodrich says, “I hope to use the FPI Mag meters in the new facility because of its accuracy, ease of installation and integration with our SCADA system. “
John Callison is technical staff at McCrometer Inc. and Michael Charnholm is an application engineer at Goble Sampson Associates.
McCrometer Inc., Hemet, Calif., develops innovative, precision flowmeters for the most demanding liquid, steam and gas measurement applications in many global industries.