Vortex Meter has Advantage —Its Body Material

July 18, 2007
New to the Racine vortex line is the RVL series liquid flow meter. One advantage to utilizing an RVL, is there are no gaskets or elastomers in the meter so the only compatibility concern is the thermoplastic material used for the body construction. The RVL has no moving parts, and the meter provides a repeatable ±1% full-scale accurate measurement without fluid contamination. The RVL series flow meter is available in PVDF, Polypropylene, PVC and CPVC, to suit a variety of fluids and process systems. Unlike stainless steel or paddle wheel designs, the RVL is perfect for aggressive or easily contaminated flow media. Suitable applications run from corrosive chemicals to ultra-pure water. For semiconductor and other sensitive environments, RVL meters are cleaned and bagged to Class1000 clean room standards. Flow rates are measured electronically, using accurate vortex shedding technology. As fluid moves across a bluff body or "strut", vortices are formed downstream. These shed vortices cause pressure fluctuations which are detected by a highly-sensitive piezoelectric crystal in the meter body, and are converted to an analog output signal. The vortex-shedding frequency is directly proportional to fluid velocity. The RVL is precalibrated for specific use, but may be recalibrated in the field with the use of a PC-based software program, with no reduction in accuracy.• Measured: Liquids • Connection: Butt or NPT thread • Turndown Ratio: 12:1 (except ¼" meter size; 8:1) • Accuracy: ±1% of full scale, 4-20 mA and 0-5 Vdc; ? ±2% of full scale, frequency pulse • Repeatability: ±0.25% actual flow • Output Signal: 4-20 mA, 0-5 Vdc or frequency pulse (source-sink driver; ? 1A source / 1.5A sink; typical output resistance 10 Ohms) • Power Supply: 13 to 30 Vdc • Enclosure: NEMA 4X (IP 66) • Response Time: 2 seconds minimum, step change in flow • Certifications: CSA File: 215035 • CSA Standard C22.2 No. O-M and No. 142-M