Condensed Version of Operator s Manual For The VI/VP700 Series Flowmeter and VI800 Series Flowmeter Warranty Agreement J-TEC Associates warrants this product to be in good working order for a period of twelve (12) months from installation. This warranty period will not exceed eighteen (18) months from the date of purchase and is valid only if the warranty form is returned validating the date of installation. If the warranty form is not received by J-TEC within six months of the date of sale, noting the date of installation, the warranty period will be 12 months from the date of purchase. Introduction The VI700, VP700 and VI800 Series Flowmeters are a family of flowmeters designed to provide accurate and repeatable gas flow measurement in volumetric flow. The sensors employ a patented ultrasonic technique to measure a form of turbulence created in the flow stream. This turbulence, known as the Von Karman Vortex Street, is related to the volumetric flow through the pipe. The flowmeter has two types of outputs. One output is a pulse train whose frequency is directly proportional to the volumetric flow. The other output is a 4-20 milliampere (ma) current source whose current ouput is proportional to the flow. Both outputs can be used simultaneously if desired. Each VI/VP Series Flowmeter is precisely calibrated against flow standards traceable to NIST (National Institute of Standards and Technology). The VP Series Flowmeters are for pipe diameters four inches or less, and are installed between 150 lb. flanges. These flowmeters are calibrated in volumetric flow rates i.e. CFM (Cubic Feed Per Minute). The VI Series Flowmeters are insertion-style retractable flowmeters that are installed through the walls of a pipe or duct larger than three inches. These flowmeters can be installed through a 2-inch full port valve, which permits the unit to be retracted or inserted manually without shutting down the system. NOTE: Caution should be used when inserting or retracting at pressure exceeding 60 PSIG (4.14 BARG). Installation/Installation Location The flowmeter has been shipped completely assembled, tested and ready to install and operate in its permanent location. The VI/VP Series Flowmeters use a patented ultrasonic technique to measure volumetric flow. J-TEC recommends a minimum of 20 pipe diameters upstream of any obstruction such as elbows and valves. A minimum of 10 pipe diameters is recommended from the meter itself. For shorter distances, consult factory for change in accuracy and performance. An ultrasonic noise can interfere with this technique, therefore high intensity ultrasonic noise sources should not be located upstream or downstream from the sensor. Common ultrasonic noise sources include the following: 1. Slightly cracked valves operating with large pressure drops. 2. Small pipe leaks in high pressure systems. 3. Venturies operating at near-sonic flow rates. 4. Sonic nozzles. If these ultrasonic noise sources cannot be eliminated, the meter should be mounted with at least one elbow between the flowmeter and the noise source. The sensor should be installed with at least 20 pipe diameters of straight pipe upstream and 10 pipe diameters downstream. Shorter upstream/downstream piping may be used although a shift in calibration may occur. The VP700 Series flowmeters are designed to mount between two ANSI 150 lb. flanges. The flowmeter should be mounted so its inside diameter is centered inside the pipe. The labeling of the flow direction on the flowmeter should be aligned with the flow in the pipe. If liquids or condensation can be present in the flow, the sensor should be installed so that liquids will not accumulate on the ultrasonic transducers (the small buttons on either side of the vortex strut). Gaskets (not provided) are necessary between the sensor and the ANSI flanges. Insure that these gaskets are properly installed and do not protrude into the flow stream. CAUTION: Avoid bending the vortex strut or damaging the transducers during installation. Do not remove cover plates while unit is operating in the system. The VI Series Insertion Flowmeters are designed to mount on a standard ANSI 150 lb., 2-inch pipe flange. The labeling of the flow direction on the sensor should be aligned with the flow in the pipe. If liquids or condensation can be present in the flow, the sensor should be installed so that liquids will not accumulate on the ultrasonic transducers (the small buttons on either side of the vortex strut). The VI Series Insertion Flowmeters have a torque requirement for the conax fitting which is 90-100 ft. lbs. for securing the stem.
Electrical Installation Electrical connections for the flowmeter are made using screw-type terminals located inside the AdaletTM enclosure. To expose these terminals, remove the lid from the smaller end of the enclosure. Flowmeter Wiring A three to four conductor cable made of 12 to 20 AWG solid or stranded wire is required to make connections to the flowmeter. The maximum length depends upon the function. For installation in noisy environments, shielded wires are recommended. For twisted pairs, group power + and power - together and the two ouputs together if the pulse output is used. The flowmeter requires a minimum of +12 VDC for proper operation. The maximum cable length for the power depends upon the supply voltage and wire size. SEE FIGURE E (Flowmeter Terminal Functions) on Page 3 Current Line The current output may be used by taking the current output to the load and then return either to the sensor with a dedicated line or to the power supply negative return. If a dedicated return to the flowmeter is used, see the Table below for the maximum allowable line resistance. Maximum Line Resistance = Total Line Resistance + Measuring Device Resistance The following is the Maximum Line Resistance as determined by the voltage being used: Voltage at Flowmeter Input Maximum Line Resistance 24 to 30 Volts 815 Ohms 15 to 24 Volts 365 Ohms 12 Volts 215 Ohms To determine the Total Line Resistance, use the following equation: Ohm/Ft depends on the wire size (AWG) used: Line Length x Ohm/Ft = Total Line Resistance 12 AWG = 0.00162 OHM/Ft 14 AWG = 0.00258 Ohm/Ft 16 AWG = 0.00420 Ohm/Ft 18 AWG = 0.00651 Ohm/Ft 20 AWG = 0.01035 Ohm/Ft Pulse Line The pulse output is a secondary output and is not intended for long transmission. The load on this line must be 50,000 Ohms minimum and 1,000 picofarads maximum. The capacitance requirements generally limit lengths to 100 feet of shielded cable. Operation The flowmeter s 4-position terminal strip provide all the connections needed to operate the flowmeter. Power (PWR) and Ground (GND) Terminals The PWR and GND terminals ( + and - ) are used for the flowmeter s power supply. This power supply should be +12 to +28 VDC and be capable of supplying 75 ma to the flowmeter. CAUTION: Do NOT wire PWR and CUR without first connecting the GND wire. Current (CUR) The CUR terminal provides an output current proportional to the flow measured by the flowmeter. This output is a standard 4 to 20 ma output, where 4 ma corresponds to no flow and 20 ma indicates 100 percent (full scale) flow. The current output will not be accurate if the load resistance on the current output terminal is too high. Pulse Train (FREQ) The FREQ outputs a pulse train whose frequency is proportional to the gas flow. The pulse levels are 0 to 8 volts and the terminal is capable of sourcing and sinking up to 100 ma of current. See Figure H (Troubleshooting Chart- Flow Conditions) on Page 4 See Figure J (Troubleshooting Chart-Flow Conditions ) on Page 5 See Figure V (Rescaling of Circuit Card) on Page 6
CHASSIS GROUND SCREW TERMINAL DESIGNATOR PWR GND CUR FREQ FUNCTION Power Input (+12 to +28 VDC) Ground (-) Return for Power & Current Current (Primary Signal) Pulse Train (Secondary Signal) FIGURE E Flowmeter Terminal Functions
MAN0039 START Change Wire Check Wiring at Terminal Strip Wiring Correct? Unit have PWR on? Turn on Power Problem Current Present? Correct? Check PWR Requirements TP3 have 8 VDC? Too High? Adjust R33 to Read 4 ma Disconnect Curr Check for 4-20 ma From CUR to GND Is Freq Adjust R33 to Read 4 ma Is 4 ma Present? Check Current Loop for Open Wire PCB Bad. Consult Factory. Is Flow Really Is Freq Really Eliminate Flow Check Current Apply jumper wire between Chassis (bracket) and GND terminal Is Current 4 ma? Adjust R33 to 4 ma Done Is Freq Done FIGURE H Troubleshooting Chart Flow Conditions Look at signal at TP2. Consult factory with results of TP2. See Figure F or Figure V for proper wiring connections J-TEC Associates, Inc.
MAN0039 START Erratic? Unit Installed Correctly? Correct Positioning Adjust Flow for Value In Meter Range Is Flow Too High or Low for Range of Meter? Meter Have Valves, Regulator, Elbow or Sonic ises Upstream of Meter? Eliminate ise Source Use Setup Procedure Current Match Freq from Calibration Data Sheet? Meter Have 20 Diameters Upstream Pipe and 10 Diameters Downstream? Consult Factory or Install More Pipe Adjust R15 for Brightest Glow on LED Did LED Brightness Vary? Is Flow Reading Correctly? Unit Show Clean Pulse On FREQ Terminal? Unit Showing Actual Flow XDCR/RCVR Problem Is Pin 12 on U1 More Than 30 mvdc? XDCR/XMTR Problem Consult Factory For Further Assistance Call Factory For RMA # To Return For Repair TP2 Show Audio Signal More Than 200 mv P-P? Call Factory For RMA # To Return For Repair FIGURE J Troubleshooting Chart Flow Conditions J-TEC Associates, Inc.
RESCALING THE CURRENT OUTPUT The following procedure details the rescaling of the current output prior to installation. Applicable hookups & component locations are described in Figure V. 1. Connect power (12 to 28 VDC) to terminals marked PWR and GND on the DBA0898 Circuit Card. 2. Set Multimeter on ma DC setting and connect to CUR and GND terminals. 3. Adjust R33 for an output of 4.0 ma on the Multimeter. MAN0039 NOTES: For flows with a full scale frequency less than 2 KHz, a jumper is installed at J4. The lowest setting for frequency at 20 ma (full scale) is 650 Hz. If using flowmeter with a Flow Computer, inject 6500 Hz. For full scale frequencies below 1200Hz, remove Q2 and install a jumper between Q2-D & Q2-S. Inject full scale frequency and adjust R21 for a voltage at TP5 between 5.5 & 6.2vdc. Adjust R39 for an output of 20mA. 5. Adjust POT R21 fully counterclockwise (ccw). 4. Inject a 2-3V P-P sine wave frequency into TP2, equivalent to full scale per the data sheet. 6. Adjust POT R39 to 20mA. If unable to attain 20mA, adjust R21 to 21mA, then readjust R39 for 20mA. 7. If all adjustments have been made successfully, the unit is rescaled. FIGURE V Rescaling of DBA0898 Uniflow Circuit Card J-TEC Associates, Inc. REVISION N