The next step is planning the installation of the unit into your pipe line. You may prefer to mount the unit permanently by welding it into the line, or you might provide access for meter removal from the line by using a flanged or threaded model. Certain line connections may require the use of a gasket. It is important to choose a gasket material that will not contaminate your media, and to be sure it is chemically resistant to the fluid being transported. Universal vortex flow meters are available with a wide selection of line connection options. These options include butt, flanged, wafer, male or female thread socket, and threaded flare. Once you have chosen a connection type, it is important to specify the standard you require. For example, our flange units are available in ANSI, DIN, or JIS standards.

MAXIMUM FLOW RATES
Maximum flow rates are indicated on the V1, V2, V3, and V4 specification pages in this catalog. You can safely and accurately measure up to 125% of the maximum flow rates listed, although units with the HT option cannot be over-ranged. The signal for 125% over-ranging would be 24 mA. You must make sure you have sufficient voltage to over-range a meter.

OUTPUT AND DISPLAYS
Universal vortex flow meters come with a variety of output options. The standard output is an analog signal ranging from 4 to 20 mA. Pulse outputs are also available. For remote Indication Clark supplies a pulse output option on all units for use with model Vorsite™ 2000 remote indicator/controller. The pulse option is for use only with Vorsite 2000 units, and is not designed to be used with other brands. The Vorsite 2000 unit is also available with two 4-20 mA analog outputs. All Universal vortex flow meters are designed to be standalone units if required. Each unit can have its own individual local LCD flow rate display. The readout can be mounted in a variety of positions for convenient readability. For specifications, dimensions, and placement of the LCD, consult the factory. The figure below shows available mounting positions.

Turbulence in the pipe line can affect the accuracy of most flow meters. Sources of turbulence are pumps, valves, or changes-in-direction in the line. To avoid these potential problems, it is standard practice to place the meter a certain distance from the turbulence source. Most manufacturers provide the user with minimum distances for their particular products. These distances are indicated in Pipe Diameters (PD). For example, 5 PD means  place the flow meter five times its inside diameter away from the source of turbulence. It is also common to provide a minimum distance downstream  between a meter and a valve or a change-in-direction.

For optimum accuracy, we recommend at least 20 PD upstream and 5 PD downstream for Universal vortex flow meters. If an upstream elbow is closely coupled to another elbow, 27 PD may be required upstream and 10 PD may be required downstream between the meter and a valve. When the diameter of the meter is smaller than the pipe line, you need at least 15 PD of pipe with  the same diameter as the meter upstream, and 5 PD downstream. Overall, 25 PD of straight run prior to the meter is required. If there is a plane change in the installation, this requirement increases to 30 PD upstream. The downstream requirement is now 2 PD of pipe with the same diameter as the meter, and a minimum of 5 PD overall of straight run. The usual 10 PD downstream between the meter and a valve is still required. If the required piping parameters are not met, there will be a corresponding reduction in accuracy.

WIRING
Connect a twisted wire pair (not provided) to the terminals of the transmitter marked + and -. If the twisted wire pair is shielded, do not connect the shield to the transmitter. The shield should be grounded at the receiver only (see Figure 4). The transmitter is reverse-polarity protected. The twisted wire pair should be connected to the receiving equipment. Twisted wire pair lengths of up to 1,000 feet are generally acceptable, and lengths up to 10,000 feet are often usable if the twisted wire pair is kept dry and distant from electrical noise sources. The receiving equipment must accept industry standard “true two wire” or “loop power” 4-20 mA process transmitter inputs. This means that the receiving equipment, such as a recorder or controller, must supply power for the transmitter along the twisted wire pair. If the receiving equipment does not provide power, a separate power supply, typically 24 Vdc at 30 mA, must be used, as shown in Figure below. There are many brands of receivers which provide 24 Vdc for this purpose. Several receivers may be connected in a series as shown in Figure below, but only one should provide power, and all should have isolated inputs. If the receiver requires 1-5 Vdc, connect a 250 Ohm, 0.1%, 1/2-watt precision resistor across its input. The voltage provided by the receiver must be within the limits shown in the Required DC Voltage Chart below. To use this figure, first add the resistance of all the receivers, indicators, etc., and the wire in the loop. If the wire resistance is unknown, use a value of 50 Ohm for a twisted wire of 1,000 feet or less with a gauge of #22 AWG or heavier. If a 1-5 Vdc receiver is used with a 250 Ohm resistor, its resistance is 250 Ohm. Only one point on the 4-20 mA loop should be grounded. Some receiving equipment inputs are grounded by their manufacturers. This is sufficient. Always follow the receiver manufacturer’s recommendations for “loop powered” or “true two wire” process transmitters. Always follow local electrical codes.

Service: General purpose.
Electrical classification: General purpose, non-hazardous, or NEMA 4X

QUICK SPECIFICATION
All flow meters 1/4" through 9" shall be of the vortex shedding style with no moving parts. Meters shall be constructed of PVC, CPVC, PP, or PVDF. Meters shall have a 12 to 1 turndown ratio with an accuracy of ±1% of full scale, ±1% of rate when used with the Vorsite 2000 flow indicator/controller, and be ±1/4% repeatable of point. All meters shall be wet calibrated at the factory and supplied with calibration records. Line connections for pipe systems shall be thread, metric butt, wafer or flange. Flare and sanitary connections shall be used for tubing systems. Output is either to be linear 4-20 mA or digital pulse to communicate with the Vorsite  2000 Flow Indicator/Controller.

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