GTS High Frequency Pulser. Technical Bulletin

Transcription

1 GTS High Frequency Pulser Technical Bulletin

2 02 Elster American Meter High Frequency Pulser System control and data acquisition in gas distribution networks begins with process sensors: sensors to detect valve position, pressure, temperature and flow. General Information Elster American Meter offers optional high frequency pulsers for its line of Gas Turbine Meters. The high frequency pulser kit consists of the radio frequency (RF) sensor, female connector, Zener barrier. It produces a square wave output signal (Form A ) with voltage approximately equal to the interface input voltage 24 VDC. The pulse output frequency varies by meter size, but is in the 0 to 1800 Hz range and is directly proportional to the gas flow rate at line conditions. When equipped with a high frequency pulser, the meter must contain an aluminum rotor, not plastic. High frequency pulsers are available as original equipment on new 4", 6" and 8" GTS meters and in retrofit kit form for existing GTS meters. Installation requires only a wrench and a screwdriver, without removing the meter from the line. Always check local codes before installing and operating any electrical equipment. The HFP output signal may be fed directly to a flow computer to convert the digital pulse to an analog signal. Applications include custody transfer billing for large industrial and commercial accounts, contract monitoring, inventory comparisons to supplier billing, LNG facility monitoring, flow rate actual of parallel runs and process flow control anywhere there is a need to sense volumetric flow of gas. Components Sensor Assembly Contains the pressure tight sensor housing, RF sensor, electronics and quick-connecting receptacle. Zener Barrier Provides an intrinsically safe barrier. Operation The High Frequency Pulser uses an RF sensor of the Eddy Current Killed Oscillator type. The oscillator in the sensor creates a radio frequency which is emitted from the coil, out from the face of the sensor. GTS Turbine Meter Internal View If metal enters the radiated field, eddy currents will circulate within the metal blades. As the metal blade moves closer to the sensor, the eddy currents increase, which causes a greater load on the oscillator. When the load becomes too great for the oscillator, it stops. The trigger circuit, sensing that the oscillator has stopped, changes the state of the switching device.

3 03 Elster American Meter Technical Data Table A Meter Size N R u R I G Meter Drive 4", 45 / ", 45 / ", 45 /30 18/ /47 41/64 54/35 48/60 66/22 67/ To convert to a metric output, multiply the calculated K Factor by ft. 3 /m 3. K Factor Calculation When installing a High Frequency Pulser Kit on an existing GTS Meter, K Factors can be calculated as outlined below: K Factor = N R u R I G CGR N R u R I G CGR Number of Rotor Blades Ratio of Rotor Rev to Upshaft Rev %A/100% Meter Drive Value Ratio of Intermediate Adjustment Gears Gear Box Ratio (without change gears) Change Gear Ratio (See Accuracy Certificate) %A Percent Accuracy of Mechanical Output CGR and %A are obtained from the accuracy certificate. When using a single K Factor, select %A at approximately 50 to 60% of the meter s maximum capacity. Table B - GTS Meter Change Gear Ratios and Teeth Ratio Number "A" Gear Teeth "B" Gear Teeth Change Gear Ratio (CGR) Radio Frequency (RF) Sensor Assembly

4 04 Elster American Meter Technical Data Wiring Diagram Strip White Black Red DETAIL 'A' (Cable Stripping) Signal Wire (customer supplied) 3 Wire White (Sig) See DETAIL 'A' Optional Junction Box (Customer Supplied) See Notes Cut off additional wire at jacket Sensor, Main Red (Pos, +) Black (Gnd, ) White (Sig) Dual Zener Barrier P&F #Z779 I.S. Ground Com Signal, Main Black (Gnd) See DETAIL 'A' Red (Pos) See DETAIL 'A' Potted Conduit Flow Computer (customer supplied) The transformer isolated barrier is a dual-channel transformer-isolated, intrinsic safety barrier with a built-in amplifier which isolates and transfers discrete signals from a hazardous area to a safe area. (+) ( ) 24 Volt DC Power Source (customer supplied) Specifications Sensor Data Maximum Sensing Range: 2.54 mm (.100 inch) Maximum Pressure Rating: 1000 PSIG Operating Temperature: -40 F to 158 F Body: 300 Series Stainless Steel 1/2 14 NPSM Threaded Body Protection Rating (IEC): IP67 Maximum Switching Frequency: 4 khz Voltage Range: 9 to 25 VDC Load Current: 10 to 15 ma Connector: 3-Pin MIL-C-5015 Type Connector mates with: Amphenol: A-10SL-3S DDK: DMS-3106A-10SL-3S Elster AMCo Kit 93278K003: Connector and hookup instructions with recommended cable Output: Open Collector Maximum Off Voltage: 30VDC Maximum On Current: 0.4 Amps Intrinsic Safety Approval: CSA Entity Parameters (Gas Group D) Vmax = 30 VCD Imax = 190 ma Ci = 0 uf Li = 0.5 mh Zener Barrier Data Passive Zener Barrier, Dual Channel One Channel for Sensor Power Second Channel for Sensor Output P&F Z VDC, 327 Ohms Maximum Open Circuit Voltage (Voc): 28.6 VDC Short Circuit Current (Isc): 96.1 ma Entity Parameters (Gas Group D) Voc = 28.6 Isc = 96.1 ma Ca = 1.06 uf La = 32.1 uh Field Installation Refer to the schematic diagram above. Recommended cable: OLFLEX CAT No , 22 AWG 1. Connect the DDK quick connector to the recommended cable per the above drawing. RED to Pin A. BLACK to Pin B and WHITE to pin C. 2. Connect the DDK quick connector/cable to the RF Sensor. Connect the other end to the (optional junction box provided by the customer within 20 feet of the meter) Zener Barrier. RED to Terminal 1, BLACK to Terminal 2 (or 3) and WHITE to Terminal Ground the Zener Barrier per standard. 4. Connect Terminal 6 or 7 of the Zener Barrier to the customer s negative (return) side of the 9 to 24 VDC power source (or Flow Computer s AUX power supply). 5. Connect Terminal 8 of the Zener Barrier to the customer s positive side of the 9 to 24 VDC power source (or Flow computer s AUX power supply). 6. Configure (or select) the customer s Flow Computer signal input for high-frequency contact closure. Insure that this high-frequency contact closure mode provides an internal signal logic pull-up resistor. If not, an external pull-up resistor to the power supply will be required. Typically, 4.7 k Ohms, 1/4 Watts. 7. Connect Terminal 5 of the Zener Barrier to the customer s Flow Computer signal input.

5 05 Elster American Meter Technical Data High Frequency Pulser Kit Selection Size Part Number 4" 52927K044 6" and 8" 52927K045 Repair Parts Size Part Number 4" Sensor 94297G038 6" and 8" Sensor 94297G039 Zener Barrier 52213G013 Cable & Connector Kit 93278K003 Meter Capacity Size Approximate Maximum Pulse Rate Capacity (ACFH) Capacity (ACMH) 4" GTS 45 Rotor 1800 Hz 18, " GTS 30 Rotor 1250 Hz 23, " GTS 45 Rotor 1670 Hz 35, " GTS 30 Rotor 1290 Hz 50, " GTS 45 Rotor 1300 Hz 60, " GTS 30 Rotor 1200 Hz 88, Notes: 1. Actual frequency may vary slightly. Each meter must be individually calibrated to determine its specific pulse rate and K factor. K = pulses/cubic foot. 1/K = cubic feet per pulse 2. To determine the K factor for kit installation see above. 3. To determine the total volume that has passed through the turbine meter, multiply the number of output pulses by 1/K. 4. A calibration sheet is supplied with new GTS meter (equipped with a High Frequency Pulser) and lists the K factor in pulses per ft 3 (or m 3 ) and the reciprocal in ft 3 (or m 3 ) per pulse. 5. Maximum distance signal can travel is 500 feet without amplification.

6 About Elster Group A world leader in advanced metering infrastructure, integrated metering, and utilization solutions to the gas, electricity and water industries. Elster s systems and solutions reflect over 170 years of knowledge and experience in measuring precious resources and energy. Elster provides solutions and advanced technologies to help utilities more easily, efficiently and reliably obtain and use advanced metering intelligence to improve customer service, enhance operational efficiency, and increase revenues. Elster s AMI solutions enable utilities to cost-effectively generate, deliver, manage, and conserve the life-essential resources of gas, electricity, and water. Elster has over 7,500 staff and operations in 38 countries in North and South America, Europe, and Asia. Elster American Meter 2221 Industrial Road Nebraska City, NE USA T F Elster American Meter. All rights reserved. Information contained herein is subject to change without notice. Product specifications may change. Contact your Elster American Meter representative for the most current product information. Printed in the United States. EAM-TB EN-P - December 2009 Supersedes IMP