Sierra Top-Trak 820 Series, Top-Trak 820, Top-Trak 822S, Top-Trak 824, Top-Trak 820S Instruction Manual

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Sierra 820 Series
Top-Trak™ Mass Flow Meters
Models: 820, 820S, 822, 822S, 824, 824S, 826 and 827
Instruction Manual
Part Number IM-82
Revision H, November 2017
Page 2
Table of Contents Series 820 Instruction Manual
GLOBAL SUPPORT LOCATIONS: WE ARE HERE TO HELP!
CORPORATE HEADQUARTERS
5 Harris Court, Building L Monterey, CA 93940 Phone (831) 373-0200 (800) 866-0200 Fax (831) 373-4402
www.sierrainstruments.com
EUROPE HEADQUARTERS
Bijlmansweid 2 1934RE Egmond aan den Hoef The Netherlands Phone +31 72 5071400 Fax +31 72 5071401
ASIA HEADQUARTERS
Second Floor Building 5, Senpu Industrial Park 25 Hangdu Road Hangtou Town Pu Dong New District, Shanghai, P.R. China Postal Code 201316 Phone: + 8621 5879 8521 Fax: +8621 5879 8586
IMPORTANT CUSTOMER NOTICE: OXYGEN SERVICE
Sierra Instruments, Inc. is not liable for any damage or personal injury, whatsoever, resulting from the use of Sierra Instruments standard ma ss flow meters or controllers for oxygen gas. You are re­sponsible for determining if this mass flow meter or controller is appropriate for your oxygen appli­cation. You are responsible for cleaning the mass flow meter or controller to the degree required for your oxygen flow application
©
COPYRIGHT SIERRA INSTRUMENTS 2016
.
No part of this publication may be copied or distributed, transmitted, transcribed, stored in a re­trieval system, or translated into any human or computer language, in any form or by any me ans, electronic, mechanical, manual, or otherwise, or disclosed to third parties without the express writ­ten permission of Sierra Instruments. The information contained in this manual is subject to change without notice.
TRADEMARKS
Top-TrakTM and Cal-Bench TM is a Registered Trademark of Sierra Instruments, Inc. Other product and company names listed in this manual are tradem arks or trade names of their respective manu­facturers.
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Series 820 Instruction Manual Table of Contents
Table of Contents
Chapter 1 Introduction
Introduction ......................................................................... 1-1
Using this Manual .............................................................. 1-1
Safety Information ............................................................. 1-2
Receipt of System Components ........................................ 1-2
Technical Assistance .......................................................... 1-2
Top Trak Features .................................................................... 1-3
The 820 Series Flow Sensing Principle ................................... 1-4
Chapter 2 Installation
Installation Overview ............................................................... 2-1
Installing the Transducer .......................................................... 2-2
Compression Fittings ......................................................... 2-2
VCO Fittings ................................................................. 2-2
VCR Fittings .................................................................. 2-3
All 1/2-inch Size Connections ........................................... 2-3
Wiring the Transducer ............................................................. 2-4
Standard 0-5 VDC Output Signal Wiring ......................... 2-5
Optional 4-20 mA Output Signal Wiring .......................... 2-5
Remote Display Installation ..................................................... 2-6
Chapter 3 Operation
Transducer Operation ...............................................................
Transducer Accuracy ......................................................... 3-1
Referencing the Transducer to Non-Standard Conditions .... 3-2
Transducer Over-Ranging ................................................. 3-2
Zero and Span Adjustments ............................................... 3-3
Totalizer Option ................................................................. 3-4
Chapter 4 Maintenance and Repair
Transducer Cleaning ................................................................ 4-1
Flow Path Cleaning Model 822/824 ........................................ 4-2
Inlet and Outlet Screens ..................................................... 4-2
Laminar Flow Element ...................................................... 4-3
Flow Path Cleaning Model 826/827 ........................................ 4-4
Laminar Flow Element ...................................................... 4-4
Flow Path Cleaning Model 822-S/824-S ................................ 4-5
Laminar Flow Element ...................................................... 4-5
Sensor Cleaning and Inspection ........................................ 4-8
Transducer Calibration ............................................................. 4-9
Transducer Troubleshooting .................................................... 4-11
Returning Equipment to the Factory ....................................... 4-13
3-1
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Table of Contents Series 820 Instruction Manual
Appendix A Conversion Formulas and Gas Tables Appendix B 822/824 Product Specifications Appendix C 822S/824S Product Specifications Appendix D 826/827 Product Specifications
List of Figures
1-1. Top-Trak Features (Typical) ........................................ 1-3
1-2. Flow Paths through the Transducer ............................. 1-4
1-3. Flow Measuring Principle ............................................ 1-4
2-1. Piping Requirements for 1/2-inch Size Connections .. 2-3
2-2. Transducer D-Connector Pin Assignments ................. 2-4
2-3. Standard 0-5 VDC Output Signal Wiring ................... 2-5
2-4. Single Transducer Current Loop Connection .............. 2-5
2-5. Multiple Transducer Current Loop Connections ........ 2-6
2-6. Mounting the Remote Display ..................................... 2-6
4-1. Model 822/824 Flow Components .............................. 4-2
4-2. Correct LFE Position ................................................... 4-3
4-3. Model 826/827 Flow Components ............................... 4-4
4-4. Low Flow Transducer LFE Cleaning .......................... 4-5
4-5. Medium Flow Transducer LFE Cleaning ................... 4-6
4-6. High Flow Transducer LFE Cleaning ......................... 4-7
4-7. Printed Circuit Board Component Locations .............. 4-11
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Series 820 Instruction Manual Table of Contents
Cautions
Caution!
Caution!
Only qualified personnel should install the transducer.
Do not supply +DC power at the D-connector while using a
power supply at the power jack. Both supplies may be damaged.
Caution!
Operating a 12 VDC transducer at 24 VDC will cause equip-
ment damage.
Caution!
Only qualified personnel should perform transducer service, ca-
libration or troubleshooting procedures.
Caution!
When using toxic or corrosive gases, purge the unit thoroughly
with inert dry gas before disconnecting from the gas line.
Caution!
Printed circuit boards are sensitive to electrostatic discharge. To avoid damaging the board, follow these precautions to minimize the risk of damage:
 before handling the assembly, discharge your body by touching
a grounded, metal object
 handle all cards by their edges unless otherwise required  when possible, use grounded electrostatic discharge wrist
straps when handling sensitive components
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Series 820 Instruction Manual Chapter 1 Introduction
Chapter 1 Introduction
This instruction manual covers the installation, operation and maintenance of Sierra’s 820 Series product line including the fol­lowing Top-Trakª Models:
 822 Mass Flow Meter with display (nylon flow body)  824 Mass Flow Meter without display (nylon flow body)  826 Hi-Flow Meter with display (aluminum flow body)  827 Hi-Flow without display (aluminum flow body)  822-S Mass Flow Meter with display (stainless steel flow body)
 824-S Mass Flow Meter without display (stainless steel flow body)
Sierra’s Top-Trakª Mass Flow Meters are designed for precise measurement of gas mass flow. The 820 Series offers a broad range of sizes and process connections for flexibility and versatili­ty. The primary standard calibration ensures starting point accura­cy and NIST traceability. The meter’s 0-5 VDC or 4-20 mA output signal is provided for recording, data-logging or control. The op­tional display reads the mass flow rate directly in engineering units or percentage of full scale.
Using This Manual
This manual is organized into four chapters:
 Chapter 1 includes the introduction and theory of operation  Chapter 2 provides installation and wiring instructions  Chapter 3 describes transducer operation and features  Chapter 4 covers maintenance, calibration and troubleshooting
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Gas tables and conversion formulas are found in Appendix A. The product specifications and dimensional drawings are found in Appendix B.
Throughout this manual, we use the word
transducer
as a ge­neric term to represent all models of Sierra’s 820 Series Top­Trak Mass Flow Meters.
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Chapter 1 Introduction Series 820 Instruction Manual
Safety Information
Caution and warning statements are used throughout this book to draw your attention to important information.
Warning! Caution!
This statement appears with information that is important to protect people and equipment from damage. Pay very close attention to all warnings that apply to your application.
Receipt of System Components
When receiving a Sierra transducer, carefully check the outside packing carton for damage incurred in shipment. If the carton is damaged, notify the local carrier and submit a report to the factory or distributor. Remove the packing slip and check that all ordered components are present and match your specifications (as ordered). Make sure any spare parts or accessories are not discarded with the packing material. Do not return any equipment to the factory with­out first contacting Sierra Customer Service.
This statement appears with information that is important for protecting your equipme nt and performance. Read and follow all cautions that apply to your application.
Technical Assistance
If you encounter a problem with your transducer, review the confi­guration information for each step of the installation, operation and set up procedures. Verify that your settings and adjustments are consistent with factory recommendations. Refer to Chapter 4, Troubleshooting, for specific information and recommendations.
If the problem persists after following the troubleshooting proce­dures outlined in Chapter 4, contact Sierra Instruments by fax or by E-mail (see inside front cover). For urgent phone support you may call (800) 866-0200 or (831) 373-0200 between 8:00 a.m. and 5:00 p.m. PST. In Europe contact Sierra Instruments bv at +31 20
6145810. When contacting Technical Support, make sure to include this information:
 the flow range, serial number, Sierra order number and
model number (all marked on the transducer nameplate)
 the problem you are encountering and any corrective action
taken
 application information (gas, pressure, temperature, pipe
and fitting configuration)
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Series 820 Instruction Manual Chapter 1 Introduction
Top-Trak Features
Standard Top-Trak Mass Flow Meters require a 12 to 15 VDC ex­ternal power source (24 VDC input power optional). The transduc­er’s 0 to 5 VDC output signal allows for flow recording, data-logging or control. A 4 to 20 mA output signal is optionally available. Input power and output signal connections are made via the 9-pin sub­type D-connector located on the side of the transducer. An addi­tional input power jack is located just below the D-connector. (It is important to connect input power at only one location.)
The transducer shown below is a typical example of a 822 Series Top-Trak Mass Flow Meter. Other models may vary slightly in their appearance but are operationally equivalent.
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Figure 1-1. Top-Trak Features (Typical)
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Chapter 1 Introduction Series 820 Instruction Manual
The 820 Series Flow Sensing Principle
The operating principle of Top-Trak transducers is based on heat transfer and the first law of thermodynamics. During operation process gas enters the instrument’s flow body and divides into two flow paths, one through the sensor tube, the other through the la­minar flow element bypass. The laminar flow bypass generates a pressure drop, P1–P2, forcing a small fraction of the total flow to pass through the sensor tube (m1).
Figure 1-2. Flow Paths through the Transducer
Two resistance temperature detector (RTD) coils around the sensor tube direct a constant amount of heat (H) into the gas stream. In actual operation, the gas mass flow carries heat from the upstream coil to the downstream coil. The resulting temperature difference (?T) is detected by the RTD coils and gives the output signal. Since the molecules of the gas carry away the heat, the output sig­nal is linearly proportional to gas mass flow.
Figure 1-3. Flow Measuring Principle
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Series 820 Instruction Manual Chapter 2 Installation
Chapter 2 Installation
Installation Overview
To ensure a successful installation, inlet and outlet tubing should be clean and free from burrs or rims caused by cutting prior to plumbing the transduc­er into the system. The protective caps covering the inlet/outlet fittings should not be removed until immediately prior to installation.
Before installing the transducer, verify the following:
1. Make sure the installation site meets the specific operating parameters recorded on the transducer’s nameplate. Each transducer is factory­configured for a specific gas and flow range. If the operating pressure is more than 50 psi (3.4 bar) away from the calibration pressure, it is advis­able to return the unit to the factory for re-calibration. (Adjusting zero may be sufficient to remain within specification.)
2. Do not locate the transducer in areas subject to sudden temperature changes, moisture, drafts or near equipment radiating significant amounts of heat. Make sure to allow adequate space for cable connectors and wir­ing.
3. For 1/2-inch size inlet/outlet process connections on models 826 and 827 make sure the location meets the minimum number of recommended pipe diameters upstream and downstream of the transducer. A minimum of 5 inches (127 mm) upstream and 2-1/2 inches (64 mm) downstream is al­ways recommended. (not necessary for other models)
4. Horizontal mounting is preferable. Vertical mounting is possible with best results achieved when the factory calibration is specifically per­formed for vertical mounting. In vertical positions zero shift will occur depending on the gas pressure at zero flow.
5. If the gas contains any particulate matter, install an in-line filter prior to the transducer. Recommended filter size: 15 micron for flows of 10 sccm to 30 slpm, 30 micron for above 30 slpm.
6. If a potential over-flow condition exists, insert a valve or critical orifice in the line to limit flow to approximately 25 percent above the full scale range of the meter.
7. Confirm that the transducer o-ring material is compatible with the gas to be measured.
8. For remote displays, confirm the supplied cable is of sufficient length to connect the components.
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Chapter 2 Installation Series 820 Instruction Manual
Installing the Transducer
Follow the installation instructions that apply to your transducer’s
Caution!
Only qualified personnel
should install the
transducer.
process connection. For all 1/2-inch size process connections, observe the piping recommendations given on page 2-3. Before operation, all plumbing should be checked carefully for leaks and the transducer purged with dry nitrogen.
Compression Fittings
1. Position the transducer with the flow direction arrow pointing downstream in the direction of flow.
2. Verify the position of the front and back ferrule. Insert the tubing into the fitting. Make sure that the tubing rests firmly on the shoulder of the fitting and that the nut is finger tight. (Do not mix or interchange parts of tube fittings made by different manufactur- ers.)
3. Hold the body steady with a backup wrench.
tighten the nut 1-1/4 turns from finger tight. For 1/8-inch, 1/4- inch and 3∕8-inch sizes, tighten only 3/4 turn from finger tight.
over-tighten!
4. Check the system’s entire flow path thoroughly for leaks. (Do not use liquid leak detectors, instead monitor pressure decay. Over­exposing the transducer to leak detector fluid may damage the unit.)
For 1/2-inch size,
Do not
VCO Fittings
1. Position the transducer with the flow direction arrow pointing
2. Install new o-rings compatible with the gas to be used. (Do not mix
3. Hold the body steady with a backup wrench.
4. Check the system’s entire flow path thoroughly for leaks. (Do not use
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downstream in the direction of flow.
or interchange parts of tube fittings made by different manu­facturers.)
Tighten the nut
finger tight and then 1/4 turn tighter with a wrench.
tighten!
Do not over-
liquid leak detectors, instead monitor pressure decay. Over- exposing the transducer to leak detector fluid may damage the unit.)
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Series 820 Instruction Manual Chapter 2 Installation
1/4 inch Female NPT Connections
1. Position the transducer with the flow direction arrow pointing in the di­rection of flow.
Use a good quality paste pipe thread sealant. Apply to pipe threads.
2.
3. Tighten the pipe no more than 1 turn past hand-tight. Caution! Do not over-tighten. Damage to the instrument may result.
1/2-Inch Size NPT Connections
1. Install a section of straight pipe at least ten pipe diameters in length up-
stream of the transducer. Also, allow at least five pipe diameters down­stream for accurate operation. DO NOT use reducers. If the preceeding components in the flow path create disturbances extend the upstream pipe length.
2. Position the transducer with the flow direction arrow pointing down-
stream in the direction of flow.
3. Tighten fittings until leak tight (refer to published standards for specific
recommendations).
(standard on nylon flow bodies
)
4. Check the system’s entire flow path thoroughly for leaks. (Do not use liq-
uid leak detectors, instead monitor pressure decay. Over-exposing the transducer to leak detector fluid may damage the unit.)
Figure 2-1 Piping Requirements for all 1/2-Inch Size Process Connections
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Chapter 2 Installation Series 820 Instruction Manual
r
e
t
Caution!
Do not supply +DC powe
at the D-connector whil using a power supply a the power jack. Both sup-
plies may be damaged.
Caution!
Operating a 12 VDC trans-
ducer at 24 VDC will cause
equipment damage.
Wiring the Transducer
Standard Top-Trakrm transducers require a 12 to 15 VDC power supply (15 VDC nominal, 100 mA maximum). 24 VDC input power is optional. Transducers are connected to the power supply through
either
the dedicated DC power jack or through the 9-pin D-connector located on the side of the enclosure. Before powering the unit, check the transducer’s nameplate to confirm input power:
 PV1 = 12 to 15 VDC  PV2 = 24 VDC
Note: operating a 24 VDC transducer at 12 to 15 VDC will result in unreliable operation.
The transducer’s standard 0 to 5 VDC (4-20 mA optional) output sig- nal is available through the D-connector. The mating connector is in- cluded with the transducer. Connection details are given on the fol- lowing pages.
When the transducer is configured for a remote display, signal con­nections are made via the 9-pin connector. Input power connections are not included in the standard interface cable. Power connections for the display and the transducer are shared when the connector is wired for a remote display. Optionally the input power can be applied at the power jack (either 12 volts (PV 1) or 24 volts (PV2). Remote display mounting dimensions are given at the end of this chapter.
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Series 820 Instruction Manual Chapter 2 Installation
Figure 2-2. Transducer D-Connector Pin Assignments
Note: The power jack requires a plug that has a 2.5mm inner diameter and a 5mm outer diameter. The center is positive (+).
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Chapter 2 Installation Series 820 Instruction Manual
Standard 0-5 VDC Output Signal Wiring
The standard 0-5 VDC output signal flows from Pin 3 (0-5 VDC Out) through the load (1K Ohm minimum) to Pin 7 (Power Common). The figure below is a typical example of input power and output signal connections.
Figure 2-3. Standard 0-5 VDC Output Signal Wiring
Optional 4-20 mA Output Signal Wiring
The optional 4-20 mA output signal flows from Pin 9 (4-20 mA Out) through the load (50 to 500 Ohms maximum) to Pin 7 (Power Com­mon). The figure below is a typical example of input power and output signal connections. (Multiple transducer current loop output connec­tions are given on the next page.)
Figure 2-4. Single Transducer Current Loop Connection
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s
Series 820 Instruction Manual Chapter 2 Installation
Figure 2-5. Multiple Transducer Current Loop Connection
Remote Display Installation
Mount the remote display at a convenient location within reach of the supplied interface cable. The maximum cable length is 100 feet (30 m).
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Figure 2-6. Mounting the Remote Display
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Series 820 Instruction Manual Chapter 3 Operation
Chapter 3 Operation
The output signal of the transducer is either 0-5 VDC (standard) or 4-20 mA (optional). The output signal is linear and proportional to the gas mass flow rate. For example, for a 0-5 VDC output signal,
5.00 VDC is the output signal for the full scale listed on the trans­ducer’s nameplate, 2.50 VDC is for one-half of full scale, and 0.00 VDC is for zero flow. For a 4-20 mA output signal, 20.00 mA is the output signal for the full scale, 12.00 mA is for one-half of full scale, and 4.00 mA is for zero flow.
Transducer Operation
When the transducer is installed and the system has undergone a complete leak check:
1. Apply power. The output signal will be at a high level for the first 10 to 20 seconds while the sensor warms up to its normal operating temperature range. Assuming zero flow, the output signal will then drop to zero (or 4 mA, depending on output configuration). Allow at least thirty minutes of warm-up time.
2. For first-time start ups, perform an initial zero output check as described on page 3-3. After checking the initial zero setting, the transducer is ready to monitor the gas mass flow rate.
Transducer Accuracy
The standard accuracy of Top-Trak is ±1.5% of full scale. The ±1.5% of full scale accuracy means that the 0-5 VDC output sig­nal is accurate to within ±.075 VDC. The 4-20 mA output is ac­curate to within ±0.24 mA.
For example, the output signal for zero flow can be as much as ±.075 VDC or +0.24 mA. If the transducer has an output signal at zero flow, as long as it is within either of these two ranges, it does not mean it is malfunctioning.
For transducers with a digital display, the accuracy is simply .015 times the full scale flow rate stated on the nameplate. For exam­ple, if the full scale is 10 slpm, the digital display will be accurate to ±0.15 slpm. The reading at zero flow may be as much as +0.15 slpm and still be within the stated accuracy specification.
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Chapter 3 Operation Series 820 Instruction Manual
Referencing the Transducer to Non-Standard Conditions
The gas flow rate output of your transducer is referenced to “normal” conditions of 21 °C (70°F) and 760 mm of mercury (1 atmosphere) unless otherwise specified on the certificate of calibration. Check the stated reference conditions of your transducer. If you are comparing your transducer’s output with another type of flow meter, different reference conditions could cause a discrepancy between the flow readings.
For example, the output reading of a Top-Trak will be approximately 7% lower when referenced to 0°C rather than 21°C. To find the flow rate referenced to other standard conditions or the actual temperature and pressure conditions in the pipe where your transducer is located, see Appendix A.
Transducer Over-Ranging
If the flow rate exceeds the full scale value listed on the transducer nameplate, the output signal and digital display (if so equipped) will read a higher value. The transducer is not calibrated for over­ranged flows and will probably be both non-linear and inaccurate. Over-range conditions are indicated by the display and/or output signal going to a level above the full scale range. When the over­range condition is removed, it may take several seconds for the
transducer to recover and resume normal operation.
If the supply voltage is only 12 VDC, the over-ranged reading may exceed the full scale value by 10% maximum. If the supply voltage is higher, as with the 24 VDC option, then the output can exceed the full scale by as much as 50%, or more. Digital displays cannot exceed 3-1/2 digits (1999). If the flow rate exceeds 1999, the right­most digits will blank and only the left-hand “1” will appear on the display.
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Series 820 Instruction Manual Chapter 3 Operation
Zero and Span Adjustments
The zero and span potentiometers are accessed through the ports marked on the side of the transducer. Normally, span adjustments are not made unless you are calibrating the transducer. The span adjustment should not be used unless you have a known, precise non­zero flow rate that you wish to match. Before making any zero adjustments, confirm that the system has reached its normal operating temperature and pressure and the transducer is mounted in its final position.
For transducers without the digital display:
1. Power the transducer and allow at least 30 minutes of warm up time before attempting any adjustments. Set gas flow to zero. Confirm that no flow exists.
2. Connect a digital multimeter to Pin 3 (0-5 Out) or, Pin 9 (4-20 Out) and Pin 7 (Power Common). Check the reading. If it does not indicate 0± .05 VDC, (or 4.0± .016mA) adjust the zero poten­tiometer.
Since the output signal does not indicate negative numbers, it is necessary to adjust down from a slightly positive reading. Begin by slowly rotating the zero pot clockwise until a positive reading is indicated. To complete the zero adjustment, slowly turn the pot counterclockwise until zero is achieved, or to the point where out- put quits changing (may be slightly above zero point in some cas- es) DO NOT ADJUST DOWNWARD BEYOND THIS POINT.
For transducers with the digital display:
1. Power the transducer and allow at least 30 minutes of warm up time before attempting any adjustments. Set gas flow to zero. Confirm that no flow exists.
2. Observe the reading on the digital display. If the reading is greater than 1.0% of full scale, adjust the zero potentiometer.
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Chapter 3 Operation Series 820 Instruction Manual
820 Totalizer Operation
The optional 820 totalizer is designed to provide a totalizer func­tion within the digital display of the 820 series. It will display the flow rate, the total flow or both at once. If your instrument has this option, it is described below. Note the flow units and the totalizer units are pre-set at the factory and must be the same.
Screens:
The totalizer display has three screens which are accessed by pressing the button circled in the photo below:
Screen 1
(start-up screen shown in photo above): Flow units are
shown together with the actual flow
Screen 2 Screen 3
: Totalized flow in the same units as Screen 1 above
: Actual flow is shown together with the total flow
Totalizer:
A total of 8 digits can be shown by the totalizer ranging from .0000001 to 99999999. The decimal point will automatically shift position as the total increases. Upon reaching the maximum count (99999999), the totalizer will “roll-over”--be cleared and begin counting from zero again.
The totalizer may be cleared by going to screen 2 or 3 and then pressing the button for more then 5 seconds. The clearing of the to­talizer can be observed on the screen.
The total count is saved in non-volatile memory every 5 minutes. If the unit is switched off within 5 minutes from power-up then no total will be saved and the previous total will be shown at the next power-up.
Caution:
happen that during power up the screen remains blank. If this oc­curs, please turn the unit off and then back on again
Due to the combination of the hardware/LCD, it may
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Page 23
Series 820 Instruction Manual Chapter 4 Maintenance and Repair
Caution!
It is important that this
transducer be serviced
and/or calibrated by
qualified personnel.
Chapter 4 Maintenance and Repair
Top-Trakm transducers essentially require no scheduled mainten­ance other than periodic flow path cleaning if the gas is dirty. If an in-line filter is used, the filtering element should be periodically replaced or ultrasonically cleaned. CAUTION: If the laminar flow element is removed from any Top­Trakm flow meter, re-calibration will be required to return the in­strument to original accuracy.
Calibration of Sierra Instruments flow meters and controllers re­quires a calibrating standard of at least equal accuracy and prefera­bly an order of magnitude better than the transducer, and a skilled factory technician familiar with the Top-Trak. It is recommended that Top-Trak meters be returned to the factory for annual evalua­tion and calibration.
Included in this chapter are general instructions for:
 Transducer Cleaning Instructions ............................... page 4-1
 Transducer Calibration ................................................ page 4-9
 Transducer Troubleshooting .................................... page 4-11
 Returning Equipment to the Factory ....................... page 4-12
Transducer Cleaning
Due to transducer design variations, separate cleaning instructions are given in this chapter for each of the following models:
 Model 822/824 with nylon flow body  Model 826/827 with aluminum flow body  Model 822-S/824-S with stainless steel flow body
When toxic or corrosive gases are used, the transducer must be thoroughly purged with inert dry gas before disconnecting from the gas line. Transducers used with toxic or corrosive gases SHOULD NOT BE returned to the factory since they constitute a safety ha­zard. Contact the factory with specific questions.
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t
Chapter 4 Maintenance and Repair Series 820 Instruction Manual
Flow Path Cleaning Model 822/824
Figure 4-1. Model 822/824 Flow Components
Caution!
When using toxic or cor rosive gases, purge the unit thoroughly with iner dry gas before discon­necting from the gas line.
Inlet and Outlet Screens
1. Remove the transducer from the system.
2. Remove inlet and outlet fittings.
3. Pull out the laminar flow element (LFE) holddowns.
4. Replace or clean the inlet and outlet screens.
5. Re-assemble components. When the transducer is installed in the system, leak test the connection.
6. To be within the original accuracy, calibrate the transducer (see page 4-9).
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Series 820 Instruction Manual Chapter 4 Maintenance and Repair
Laminar Flow Element
The laminar flow element (LFE) is a precision flow divider which
Caution!
the LFE from the meter will change your calibra- tion.
the LFE unless you are prepared to re-calibrate
Removing
Do not remove
the instrument.
diverts a preset amount of flow through the sensor tube. The par­ticular LFE used depends on the gas and flow range of the instru­ment. To clean or inspect the LFE:
1. Remove the transducer from the system.
2. Remove the inlet and outlet fittings and inlet screen.
3. The LFE has a slightly tapered shape with the larger diameter on the upstream (inlet) side. To remove, use a blunt object which does not mar the flow channels to push the LFE from the outlet side to the inlet side. A 3/8-inch (9 mm) nut driver works well.
4. Clean the LFE using an alcohol-based solvent. Make sure to carefully clean all active flow channels in the LFE.
5. Re-install the LFE making sure to press it in the correct dis­tance as shown below.
6. Re-assemble remaining components. When the transducer is installed in the system, leak test the connection. Re-zero the transducer (see Chapter 3).
7. Calibrate the instrument (see page 4-9).
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Figure 4-2. Correct LFE Position
3
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Chapter 4 Maintenance and Repair Series 820 Instruction Manual
Flow Path Cleaning Model 826/827
Caution!
the LFE from the meter will change your calibra- tion.
the LFE unless you are
prepared to re-calibrate
Removing
Do not remove
the instrument
.
Laminar Flow Element
The laminar flow element (LFE) is a precision flow divider which diverts a preset amount of flow through the sensor tube. The par­ticular LFE used depends on the gas and flow range of the instru­ment. To clean or inspect the LFE:
1. Remove the transducer from the system.
2. Remove the 6-32 hex nuts and washers. Remove the end caps. Note the position of the three (3) LFE elements.
3. To remove the LFE, use a blunt object which does not mar
the flow channels to push the LFE from the flow body.
4. Clean the LFE using a suitable solvent. Make sure to carefully clean all active flow channels in the LFE.
5. Re-install the LFE making sure to position it with both ends even with the transducer flow body.
6. Re-assemble remaining components. When the transducer is installed in the system, leak test the connection. Re-zero the transducer (see Chapter 3).
7. Perform a calibration (see page 4-9).
Figure 4-3. Model 826/827 Flow Components
4-4 IM-82
Page 27
Series 820 Instruction Manual Chapter 4 Maintenance and Repair
Flow Path Cleaning Model 822-S/824-S
Caution!
the LFE from the meter will change your calibra- tion.
the LFE unless you are prepared to re-calibrate
Removing
Do not remove
the instrument
.
Laminar Flow Element
The laminar flow element (LFE) is a precision flow divider which diverts a preset amount of flow through the sensor tube. The LFE is made of precision machined 316 stainless steel. The particular LFE used depends on the gas and flow range of the instrument. Should the LFE require cleaning or inspection due to deposition, use the appropriate cleaning procedure which is specific to flow body size.
Figure 4-4. Low Flow Transducer LFE Cleaning
Low Flow Transducers:
The LFE is accessed by unscrewing the main inlet fitting and re­moving it from the flow body. The LFE is screwed into the inlet fitting, which has been specially machined for this purpose. To access the components:
1. Remove the transducer from the system.
2. The inlet filter screen is held in place in the inlet fitting by the
.
LFE. Disassemble by holding the fitting steady with a wrench and unscrewing the LFE with a medium flat-tipped screwdriv­er.
IM-82 4-
3. Remove the LFE assembly taking care not to bend the inlet screen. Inspect the sealing O-ring and replace if necessary. In­spect the inlet screen and replace if corroded or damaged. Light to medium particulate contamination can be cleaned by back washing with a suitable solvent. Air dry thoroughly.
5
Page 28
Chapter 4 Maintenance and Repair Series 820 Instruction Manual
4. Inspect the LFE for damage and replace if necessary. Remember that removal or replacement of the LFE or inlet screen requires transducer re-calibration.
5. Re-assemble components. When the transducer is installed in the system, leak test the connection. Re-zero the transducer (see Chapter 3).
6. To be within the original accuracy, calibrate the transducer (see page 4-9).
Caution!
the LFE from the meter will change your calibra- tion.
the LFE unless you are prepared to re-calibrate
Removing
Do not remove
the instrument.
Figure 4-5. Medium Flow Transducer LFE Cleaning
Medium Flow Transducers:
In the medium flow body, the LFE assembly consists of the honey­comb laminar flow element, inlet screen, 0.63 inch long standoff, two ranging washers, 2-1Ú4 inch long 4-40 screw and 4-40 nut. Range changes in the honeycomb element are made with various diameter ranging washers. To access the components:
.
1. Remove the unit from the system.
2. Access the LFE by unscrewing the four 10-32 socket head cap screws from the inlet side of the flow body and remove the in­let end cap. (Note the position of the screws, one has a shorter length.)
3. Remove the LFE assembly taking care not to bend the inlet screen. Inspect the sealing O-ring and replace if necessary. In­spect the inlet screen and replace if corroded or damaged. Light to medium particulate contamination can be cleaned by back washing with a suitable solvent. Air dry thoroughly.
4-6 IM-82
Page 29
Series 820 Instruction Manual Chapter 4 Maintenance and Repair
4. Inspect the honeycomb element for damage and replace if ne­cessary. Replacement of the LFE or inlet screen requires trans­ducer re-calibration.
5. Re-assemble components. When the transducer is installed in the system, leak test the connection.
6. To be within the original accuracy, calibrate the transducer (see page 4-9).
Figure 4-6. High Flow Transducer LFE Cleaning
Caution!
the LFE from the meter will change your calibra- tion.
the LFE unless you are prepared to re-calibrate
Removing
Do not remove
the instrument
.
High Flow Transducers:
The high flow LFE is similar to the honeycomb element used in the medium flow body but larger in diameter. The high flow body con­sists of four parts: inlet tube, inlet cap, main flow body and end cap. The inlet tube is only removed to inspect and replace the sealing O­ring between the inlet tube and inlet cap. To access the components:
1. Remove the unit from the system.
2. To remove the inlet screen, remove the four 1∕4-28 socket head cap screws on the inlet side of the flow body and separate the inlet cap from the main flow body.
3. Inspect the inlet screen for damage and corrosion and replace if necessary. Light to medium particulate contamination can be cleaned by back washing with a suitable solvent. Air dry thorough­ly.
4. Inspect the sealing O-ring for damage and replace if necessary. The inlet screen is mounted with the fine mesh side facing the in­let.
IM-82 4-
5. To remove the LFE loosen and remove the four threaded rods holding the end cap to the main flow body. Separate the end cap from the main flow body and remove the LFE assembly. The LFE
7
Page 30
Chapter 4 Maintenance and Repair Series 820 Instruction Manual
assembly consists of: 6-32 x 31∕8 inch long screw, a #6 washer, two ranging washers, honeycomb laminar flow element, LFE, spacer, inlet filter, and 6-32 nut.
6. Inspect the honeycomb element for damage and replace if ne­cessary. Replacement of the LFE or inlet screen requires trans­ducer re-calibration.
7. Re-assemble components. When the transducer is installed in the system, leak test the connection.
8. To be within the original accuracy, calibrate the transducer (see page 4-9).
Caution!
corrosive gases, purge the un it thoroughly with inert dry gas before disconnecting from the gas line.
When using toxic or
Sensor Cleaning and Inspection
Due to sensor design variations, the following sensor cleaning in-
structions are for Model 822-S/824-S
models must be returned to the factory.
Sensor cleaning is accomplished by simply rodding out the sen­sor with the Sensor Cleaning Stylette, part number “CKÓ availa­ble from Sierra. A 0.028 inch diameter piano wire may also be used.
To access the sensor for inspection or cleaning:
1. Remove the transducer from the system. Remove the two sock­et head access port plugs with a 1Ú4-inch Allen wrench. Visual­ly inspect the sensing ports and sensor.
1. Use a hemostat or tweezers to push the cleaning wire into the downstream opening of the sensor tube. Do not force the cleaning wire, move it back and forth–DO NOT TWIST OR ROTATE.
only
. All other transducer
2. Flush the sensor tube with a
4-8 IM-82-E
non-residuous solvent compatible with the O-ring material. In cases where solids are deposited in sensor, units should be returned to factory for complete cleaning and re-calibration.
Page 31
Series 820 Instruction Manual Chapter 4 Maintenance and Repair
3. Blow dry all parts with dry nitrogen and re-assemble. When the transducer is installed in the system, leak test the connection. Re-zero the transducer (see Chapter 3).
Transducer Calibration
Calibration of Sierra’s flow meters requires a calibration standard of at least four times the accuracy of the transducer. Sierra’s Cal-
Caution!
It is important that this
transducer be calibrated
only by qualified personnel.
Bench Automated Primary Calibration System is the preferred me­thod of calibration and is used at the factory for all calibrations from 10 sccm up to 50 slpm. Most calibrations can be performed with a digital voltmeter (DVM) or multimeter with 0.25% accuracy and four digits, dry nitrogen and the K-factor tables included in this manual. Flow meters require a metering valve for setting a constant flow rate.
The following procedures are offered as guidelines for calibration. It is always best to return the transducer to the factory for calibra­tion. Calibration checks and minor adjustments to the zero and full scale are made via the access ports in the enclosure. If the linearity needs adjustment (when installing a different bypass to change the range) skip Step 2 and Step 3. If linearity does not need adjust­ment, complete only Steps 1 through 3.
Step 1. Warm Up
Plug in the unit to be calibrated and allow at least 30 minutes warm up time before attempting any adjustments.
Step 2. Zero Adjust
Slide open the zero and span access doors. Connect a DVM or multimeter to the transducer output pins. Adjust the zero potenti­ometer for 0.0 volts (4 mA) at zero flow.
Step 3. Check Full Scale
Generate full scale flow using a metering valve in-line with the unit under test. Compare the indicated flow rate with the flow standard reading. If they agree to within ±10%, adjust the span po­tentiometer for exact agreement. If the readings do not agree with­in ±10%, attempt to determine the cause of disagreement. Possibil­ities are:
 leaks in the system or in the transducer  wrong or improper use of K-factor  wrong or improper correction for temperature and pressure  partially clogged or dirty sensor tube
IM-82 4-
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Page 32
Chapter 4 Maintenance and Repair Series 820 Instruction Manual
• replacement of components in the flow path do not exactly match the original parts
This completes transducer calibration. To adjust linearity, continue with Step 4.
Step 4. Adjusting Linearity (see Figure 4-7)
First gain access to the printed circuit board inside the enclosure:
1. For units with the digital display, carefully rotate the display until it hits the top plate. Slide the display’s two side panels up and remove. Move the display aside taking care not to damage the connecting cable.
2. Remove the two Phillips head screws from the top of the trans­ducer enclosure. Remove the two Phillips head screws from the back of the transducer enclosure. Pull the enclosure panels off.
3. Orient the transducer with the component side of the circuit board facing you. Plug in the transducer and allow to warm up for at least 30 minutes.
Step 5. Zero Adjust
Connect a DVM to the transducer output pins. Adjust the zero po­tentiometer for 0.0 volts (4 mA) at zero flow.
Step 6. Calibrate 25%
Use the calibration standard to set a flow rate of 25% of full scale. Adjust the span potentiometer R21 for 1.25 volts (8 mA) at the output of the transducer.
Step 7. Calibrate 50%
Increase the flow rate to 50% of full scale. If the output is within +0.05 V (0.2 mA), no adjustment is necessary. If the output is beyond these limits, install a jumper block at J1 in the appropriate position (see Figure 4-7). Adjust R25 for the proper reading.
Step 8. Calibrate 75% and 100%
Set the flow to 75% of full scale. If the output is outside the limits set in Step 7, install a jumper block in J2 in the appropriate posi­tion. Adjust R27 for the correct reading. Repeat this procedure for 100% flow using R29. Repeat Steps 6 through 8 at least one more time.
4-10 IM-82
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Series 820 Instruction Manual Chapter 4 Maintenance and Repair
Figure 4-7. Printed Circuit Board Component Locations
Transducer Troubleshooting
When you suspect that the transducer is not operating correctly, there are a few simple checks that can be made before taking the unit out of service:
1. Make certain that there are no leaks in the gas line.
2. Check that all cables are connected and are in good condition.
3. Verify that the power supply is in the correct range and properly connected to the transducer.
4. Double check connector pin outs when replacing another man­ufacturer’s transducer.
This information is provided to help locate the cause of a transduc­er failure. It is not intended to be an all inclusive repair guide. For most repairs, the unit should be returned to the factory for service.
IM-82 4-
11
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Chapter 4 Maintenance and Repair Series 820 Instruction Manual
r
Problem
Possible Cause
Solution
No output No power
Inlet filter screen clogged Clogged sensor
PCB defective
Plug in power supply Clean or replace screen Return to factory for cleaning* Return to factory for repair
Unit will not zero
Gas leak Application requires high pres­sure and non-horizontal mounting PCB defective
Find and correct leaks Re-zero transducer (see Chapter 3)
Return to factory for repair
Reads full scale with no flow
Gas leak Liquid present in system Defective sensor
Find and correct leaks Check for liquid in flow path Return to factory for repai
Output too high Incorrect calibration or K-factor
Liquid present in system Defective sensor
Correct calibration/k-factor Check for liquid in flow path Return to factory for repair
Out of calibration Dirty or clogged sensor
Change in composition of gas Gas leak LFE dirty Inlet filter screen clogged Incorrect inlet conditions (1/2-inch size models)
PCB defective
*Model 822-S/824-S see sensor cleaning instructions
Return to factory for cleaning* See K-factory tables Find and correct leaks
Clean LFE Clean or replace screen Re­plumb transducer correctly (See Chapter 2) Return to factory for repair
4-12 IM-82
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Series 820 Instruction Manual Chapter 4 Maintenance and Repair
Returning Equipment to the Factory
Factory Calibration—All Models
Sierra Instruments maintains a fully-equipped calibration laboratory. All measuring and test equipment used in the calibration of Sierra transducers are traceable to NIST Standards. Sierra is ISO-9001 registered and con­forms to the requirements of ANSI/NCSL-Z540 and ISO/IEC Guide 25.
Instructions for Returning Your Instrument for Service
The following information will help you return your instrument to Sierra Instruments' Factory Service Center and will ensure that your order is processed promptly. Prices may vary depending on the flow range, type of gas and operating pressure of your unit. To request a rough estimate of the pricing, contact your local Sierra Instruments distributor or contact one of our offices directly. A detailed quote will be provided following a full evaluation of your instrument.
Please follow these easy steps to return your instrument for fac­tory service:
Caution!
Always fully neutralize any
toxic gas trapped in- side
the instrument before
removing it from the gas
line.
1. Obtain a Return Materials Authorization (RMA) number from the Sierra Instruments website at
http://www.sierrainstruments.com/rma/login.php
2. If you require service beyond calibration, but do not know which service(s) will be required, describe the symptoms as accurately as possible on the RMA form.
.
3. Pack your instrument carefully. Use the original packaging and
foam or bubble wrap (packing peanuts NOT recommended) and include a copy of the RMA form (complete with Sierra supplied RMA number) with the unit(s).
4. Ship the unit(s) to the following address:
Sierra Instruments, Inc. Attention: Factory Service Center 5 Harris Court, Building L Monterey, CA 93940 USA
IM-82 4-
13
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Chapter 4 Maintenance and Repair Series 820 Instruction Manual
CUSTOMER SERVICE AND SUPPORT INFORMATION:
Email Technical Support: Email Sales:
FACTORY USA (Monterey, California)
PHONE: 831-373-0200 FAX: 831-373-4402
EMAIL: service@sierrainstruments.com
European Sales & Service Center (Egmond a/d Hoef, Netherlands)
PHONE: +31 72 5071400 FAX: +31 72 5071401
EMAIL: service@sierra-instruments.nl
Asia Sales & Service Center (Shanghai, Peoples Republic of China)
PHONE: FAX: +86 21 5879 85861
sales@sierrainstruments.com
TOLL FREE: 800-866-0200
+ 86 21 5879 8521
SAFETY NOTE ABOUT PURGING
service@sierrainstruments.com
WARNING: When toxic or corrosive gases are used, purge unit thoroughly with inert dry gas before discon­necting from the gas line to prevent personnel from be­ing injured when coming in contact with the instrument. If an instrument used with a toxic or corrosive gas is re­turned to the factory, a Material Safety Data Sheet (MSDS) must be enclosed & attached to the outside of the box to alert Sierra personnel of the potential hazard. Also, make sure the inlet & outlet are solidly plugged off.
4-14 IM-82
Page 37
Series 820 Instruction Manual Appendix A
Appendix A Conversion Formulas and Gas Tables
Conversion of Flow Rate to Other T and P Conditions
The flow rate of your transducer is referenced to certain “standard” conditions of temperature and pressure. Unless otherwise specified in your order, these standard conditions are 21 °C (70°F) and 760 mm of mercury (1 atmosphere). If you wish to convert to other “standard” conditions or to find the “actual” conditions in the pipe where your instrument is installed, use the following relationship:
P
1
T
2
Q2 = Q
P
2
T
1
( )1 = The standard conditions under which your instrument
was calibrated,
2
= The new standard conditions or the actual temperature
( )
and pressure conditions in the pipe,
1
= The gas mass flow rate referenced to the calibrated standard
Q
conditions (sccm or slm),
1
(1)
Q
2
= The gas mass flow rate referenced to the new standard or
actual conditions (sccm or slm—“S” means “standard,” accm or alm—“A” means “actual”),
2
P = Absolute pressure (kg/cm
or psia), and
T = Absolute temperature (°K or °R) (°K = °C + 273, °R = °F + 460).
Example 1: Changing “Standard” Conditions
If your transducer has a flow rate reading of 10.00 slm and was cali brated at standard conditions of 70°F (21°C) and 1 atmosphere (14.7 psia), and if you wish to convert this reading to standard conditions of 32°F (0°C) and 1 atmosphere, then you would use Equation (1) as follows:
14.7 460 + 32
Q2 = _________________ (10.0) = 9.28 slm
14.7 460 + 70
The flow rate referenced to 0°C will be approximately 7% lower than when referenced to standard conditions of 21 °C.
IM-82 A-1
Page 38
Appendix A Serie s 8 2 0 I nstruct i o n Manua l
A
Example 2: Finding the “Actual” Flow Rate
If the flow rate and calibrated standard conditions are as given in Example 1 and you wish to find the actual flow rate at 100°F and 30 psig, then you would use Equation (1) as follows:
14.7 460 + 100
Q2 = (10.00) = 3.47 lm
14.7 + 30 460 + 70
Calculating For a Single Gas
The following tables provide K-factors and thermodynamic prop­erties of gases commonly used with mass flow meters and control­lers. The purpose of these tables is two-fold:
1. Calibrating an “actual” gas with a reference gas. This is partic­ularly useful if the actual gas is not a common gas or if it is toxic, flammable, corrosive, etc.
2. Interpreting the reading of a flow meter or flow controller which has been calibrated with a gas other than the actual gas.
In applying the tables, the following fundamental relationship is used:
Q1/Q2 = K1/K
2
(1)
Where:
Q = The volumetric flow rate of the gas referenced to normal
conditions of 0°C and 760 mm Hg (sccm or slm),
K = The K-factor defined in equation (6),
( ) 1 = Refers to the “actual” gas, and
( ) 2 = Refers to the “reference” gas.
The K-factor is derived from the first law of thermodynamics ap­plied to the sensor tube, as described in Chapter 1:
H = µC
2
p
T
(2)
-2 IM-82
Page 39
Series 820 Instruction Manual Appendix A
A
Where:
H
= The constant amount of heat applied to the sensor tube,
µ
= The mass flow rate of the gas (gm/min)
C
p
= The coefficient of specific heat of the gas (Cal/gm);
Cp is given in the Table (at 0°C),
Δ
T
= The temperature difference between the downstream and
upstream coils, and
N
= A correction factor for the molecular structure of the gas
given by the following table:
Number of Atoms in the Gas Molecule N
Monatomic 1.040
Diatomic 1.000
Triatomic 0.941
Polyatomic 0.880
The mass flow rate, µ, can also be written as:
µ = ρQ
Where:
ρ
= The gas mass density at standard conditions (g/l);
en in the tables (at 0°C, 760 mm Hg).
Furthermore, the temperature difference, ΔT, is proportional to the output voltage, E, of the mass flow meter, or
Δ
T = aE
where:
a
= a constant.
If we combine equations (3) and (4), insert them into equation (2), and solve for Q, we get
(4)
ρ
is giv-
Q = (bN/ρCp)
(3)
(5)
IM-82
where:
b = H/aE = a constant if the output voltage is constant.
-3
Page 40
Appendix A Serie s 8 2 0 I nstruct i o n Manua l
A
For our purposes, we want the ratio of the flow rate, Q1, for an ac­tual gas to the flow rate of a reference gas, Q2, which will produce the same output voltage in a particular mass flow meter or control­ler. We get this by combining equations (1) and (5):
Q1/Q2 = K1/K2 = (N1/
ρ1Cp1)/(N2/
ρ2CP2) (6)
Please note that the constant b cancels out. Equation (6) is the funda­mental relationship used in the accompanying tables. For convenience, the tables give “relative” K-factors, which are the ratios K1/K2, instead of the K-factors themselves. In the tables, the relative K-factor is K
actual
/KN2 where the reference gas is the commonly used gas, nitro­gen (N2). The remaining columns give Cp and p, enabling you to cal­culate
directly using Equation (6). In some instances, K1/K
K1/K
2
2
from the tables may be different from that which you calculate direct­ly. The value from the tables is preferred because in many cases it was obtained by experiment. Sierra calibrates every transducer with prima­ry standards using the actual gas or a molecular equivalent reference gas. The calibration certificate accompanying the transducer cites the reference gas used.
Example 1:
A transducer is calibrated for nitrogen (N2), and the flow rate is 1000 sccm for a 5.000 VDC output signal. The flow rate for carbon dioxide at a 5.000 VDC output is:
Q
CO2/QN2
Q
CO2
= K
CO2
/K N2, or
= (0.74/1.000)1000 = 740 sccm
Example 2:
A transducer is calibrated for hydrogen (H2), and the flow rate is 100 sccm for a 5.000 VDC output signal. The flow rate for nitrous oxide (N2O) is found as follows:
Q
N2O/QH2
Q
N2O
Note that the K -factors relative to nitrogen must be used in each case.
Example 3:
= K
N2O
/K H2, or
= (0.71/1.01) 100 = 70.3 sccm
We want a transducer to be calibrated for use with dichlorosilane (SiH2Cl2) at a 100 sccm full scale flow. We wish to use the pre­ferred reference gas Freon-14 (CF4). What flow of CF4 must we generate to do the calibration?
Q
SiH2CL2 /QCF4
100/Q
Q
CF4
CF4
= 100/0.869 = 115 sccm
= K
= 0.869
SiH2CL2
/K
CF4
-4 IM-82
Page 41
Series 820 Instruction Manual Appendix A
A
Calculating Dual Gas Mixtures
Equation (6) is used for gas mixtures, but we must calculate for the mixture. The equivalent values of p, Cp, and N for a dual
gas mixture are given as follows: The equivalent gas density is:
P 󰇛ml / mT󰇜 P1 󰇛m2/mT󰇜 P2
Where:
M1m
( )1 = Refers to gas #1, and ( )2 = Refers to gas #2
The equivalent specific heat is:
Cp = F1C Where:
F F
m2=
1
󰇛m1 Pi󰇜/󰇛mTP󰇜
1
󰇛m2P2󰇜/󰇛mTP󰇜
2
Total mass flow rate (g/min).
p1
+ F2Cp2
N/
p
C
p
The equivalent value of N is:
N 󰇛Ml / mT󰇜 N1󰇛m2/mT󰇜 N2
The equivalency relationships for p, Cp, and N for mixtures of more than two gases have a form similar to the dual-gas relation­ship given above.
IMPORTANT NOTE ABOUT K-FACTORS: Please note that if you have a transducer calibrated for a gas such as methane and wish to use the K-factors to measure a gas such as air, that the inaccuracy of the measurement can range from ±5 to 10%. The use of K-factors is, at best, only a rough approximation and should not be used in applications that require a better than ±5 to 10% accuracy.
It should also be noted that certain gases, in similar “families,” will work exceptionally well with K-factors; however, those instances are only true when similar thermal properties of the gas are present.
IM-82
-5
Page 42
Series 820 Instruction Manual Appendix A
Actual Gas Symbol (Cal/g) (g/l) @
Chemical K-factor
Relative
N2
Cp Density Elastomer* Nylon
O-ring* Valve Compatible
0°C
Seat
Corrosive
Gas
Limited
Warranty
Acetylene C2H2 0.58 0.4036 1.162
Air 1 0.24 1.293
Viton® Viton®
Viton® Viton®
Allene (Propadiene) C3H4 0.43 0.352 1.787 KR
Ammonia NH3 0.73 0.492 0.76 NEO KR
Argon Ar 1.45 0.1244 1.782
Arsine AsH3 0.67 0.1167 3.478
Viton® Viton®
Viton®
KR
Boron Trichloride BCl3 0.41 0.1279 5.227 KR KR
Boron Trifluoride BF3 0.51 0.1778 3.025
Boron Tribromide Br3 0.38 0.0647 11.18
Bromine Br2 0.81 0.0539 7.13
Bromine Pentafluoride BrF5 0.26 0.1369 7.803
Bromine Trifluoride BrF3 0.38 0.1161 6.108
Viton®
Viton®
Viton® Viton®
Viton®
Viton®
KR
KR
NO
KR NO
KR NO
Bromotrifloromethane CBrF3 0.37 0.1113 6.644 Viton® Vito
(Freon-13 B1)
1,3-Butadiene C4H6 0.32 0.3514 2.413
Butane C4H10 0.26 0.4007 2.593
1-Butane C4H8 0.3 0.3648 2.503
2-Butane C4H8 CIS 0.324 0.336 2.503
2-Butane C
4H8
TRANS
0.291 0.374 2.503
Carbon Dioxide CO2 0.74 0.2016 1.964
Carbon Disulfide CS2 0.6 0.1428 3.397
Carbon Monoxide CO 1 0.2488 1.25
Carbon Tetrachloride CCl4 0.31 0.1655 6.86
Viton® Viton®
Viton® Viton®
Viton® Viton®
Viton® Viton®
Viton® Viton®
Viton® Viton®
Viton® Viton®
Viton® Viton®
Viton®
KR NO
Carbon Tetra fluoride CF4 0.42 0.1654 3.926 Viton® Vito
(Freon-14)
Carbonyl Fluoride COF2 0.54 0.171 2.945
Carbonyl Sulfide COS 0.66 0.1651 2.68
Chlorine CL2 0.86 0.114 3.163
Chlorine Trifluoride CIF3 0.4 0.165 4.125
Viton® Viton®
Viton® Viton®
Viton®
Viton®
KR NO
KR
Chlorodifluoromethane CHClF2 0.46 0.1544 3.858 Viton® KR
(Freon-22)
Chloroform CHCI3 0.39 0.1309 5.326
Viton®
KR
Chloropentafluoroethane C2CIF5 0.24 0.164 6.892 Viton® KR
(Freon-115)
Chlorotrifluromethane CCIF3 0.38 0.153 4.66 Viton® KR
(Freon-13)
* If no O-ring material is specified then O-ring to be used is Viton
YES
YES
Page 43
Actual Gas Symbol (Cal/g) (g/l) @
Chemical K-factor
Relative
N2
Cyanogen C2N2 0.61 0.2613 2.322
Cp Density Elastomer* Nylon
O-ring Valve Compatible
0°C
Seat
Viton®
KR
Cyanogen Chloride CICN 0.61 0.1739 2.742 KR KR
Cychlopropane C3H5 0.46 0.3177 1.877
Deuterium D2 1 0.1722 1.799
Diborane B2H6 0.44 0.508 1.235
Dibromodifluoromethane CBr2F2 0.19 0.15 ATEX
Dibromethane 0.47 0.075 7.76
Viton®
Viton®
Viton®
Viton®
Viton®
KR
KR
KR
KR
Dichlorodifluoromethane CCI2F2 0.35 0.1432 5.395 Viton® KR
(Freon-12)
Dichlorofluoromethane CHCl2F 0.42 0.14 4.952 Viton® KR
(Freon-21)
Dichloromethylsilane (CH
Dichlorosilane SiH2Cl2 0.4 0.15 4.506
SiCl2 0.25 0.1882 5.758
3) 2
Viton®
Viton®
KR
KR
Dichlorotetrafluoroethane C2Cl2F4 0.22 0.1604 7.626 Viton® KR
(Freon-114)
1,1-Difluoroethylene C2H2F2 0.43 0.224 2.857 Viton® KR
(Freon-1132A)
Dimethylamine (CH3) 2NH 0.37 0.366 2.011
Dimethyl Ether (CH3) 2O 0.39 0.3414 2.055
2,2-Dimethylpropane C3H12 0.22 0.3914 3.219
Ethane C2H6 0.5 0.4097 1.342
Ethanol C2H6O 0.39 0.3395 2.055
EthylAcetylene C4H6 0.32 0.3513 2.413
Ethyl Chloride C2H5CI 0.39 0.244 2.879
Ethylene C2H4 0.6
~.358
1.251
Viton®
Viton®
Viton®
Viton® Viton®
Viton®
Viton®
Viton®
Viton® Viton®
KR
KR
KR
NO
KR
KR
KR
Ethylene Oxide C2H4O 0.52 0.268 1.965 KR KR
Fluorine F2 0.98 0.1873 1.695
Fluoroform (Freon-23) CHF3 0.5 0.176 3.127
Freon-11 CCI3F 0.33 0.1357 6.129
Freon-12 CCI2F2 0.35 0.1432 5.395
Freon-13 CCIF3 0.38 0.153 4.66
Freon-13 B1 CFrF3 0.37 0.1113 6.644
Freon-14 CF4 0.42 0.1654 3.926
Freon-21 CHCI2F 0.42 0.14 4.952
Freon-22 CHCIF2 0.46 0.1544 3.858
Freon-113 CCI
FCCIF2 0.2 0.161 8.36
2
Freon-114 C2Cl2F4 0.22 0.16 7.626
Freon-115 C2ClF5 0.24 0.164 6.892
Viton®
Viton®
Viton®
Viton®
Viton®
Viton®
Viton® Viton®
Viton®
Viton®
Viton®
Viton®
Viton®
KR
KR NO
KR NO
KR NO
KR NO
KR NO
NO
KR NO
KR NO
KR NO
KR NO
KR NO
Freon-C318 C4F8 0.17 0.185 8.397 NEO NEO NO
Corrosive
Gas
Limited
Warranty
800 Only
YES
Page 44
Page 45
Actual Gas Symbol (Cal/g) (g/l) @
Germane GeH4 0.57 0.1404 3.418
Germanium Tetrachloride
Helium He 1.454 1.241 0.1786
Hexafluoroethane C2F6 0.24 0.1834 6.157 Viton® KR NO
(Freon-116)
Hexane C6H14 0.18 0.3968 3.845
Hydrogen H2 1.01 3.419 0.0899
Hydrogen Bromide HBr 1 0.0861 3.61
Hydrogen Chloride HCl 1 0.1912 1.627 KR KR
Hydrogen Cyanide HCN 1.07 0.3171 1.206
Hydrogen Fluoride HF 1 0.3479 0.893 KR KR
Hydrogen Iodide HI 1 0.0545 5.707
Hydrogen Selenide H2Se 0.79 0.1025 3.613
Hydrogen Sulfide H2S 0.8 0.2397 1.52 NEO KR
Iodine Pentafluoride IF5 0.25 0.1108 9.9
Isobutane CH(CH3)3 0.27 0.3872
Isobutylene C4H8 0.29 0.3701 2.503
Krypton Kr 1.453 0.0593 3.739
Methane CH4 0.72 0.5328 0.715
Methanol CH3OH 0.58 0.3274 1.429
Methyl Acetylene C3H4 0.43 0.3547 1.787
Methyl Bromide CH3Br 0.58 0.1106 4.236
Methyl Chloride CH3Cl 0.1926 2.253
Methyl Fluoride CH3F 0.68 0.3221 1.518
Methyl Mercaptan CH3SH 0.52 0.2459 2.146
Methyl Trichlorosilane (CH3) SiCl3 0.25 0.164 6.669
Chemical K-factor
Relative
N2
GeCL4 0.27 0.1071 9.565
Cp Density Elastomer* Nylon
O-ring Valve Compatible
0°C
Seat
2.593
Viton® Viton®
Viton®
Viton® Viton®
Viton®
Viton® Viton®
Viton®
Viton®
Viton®
Viton®
Viton®
Viton®
Viton®
Viton® Viton®
Viton® Viton®
Viton® Viton®
Viton®
Viton® Viton®
Viton®
Viton®
Viton®
Viton®
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
Corrosive
Gas
Limited
Warranty
YES
YES
Molybdenum Hexafluoride
Monoethylamine C2H5NH2 0.35 0.387 2.011
Monomethylamine CH3NH2 0.51 0.4343 1.386
Neon NE 1.46 0.245 0.9
Nitric Oxide NO 0.99 0.2328 1.339
Nitrogen N2 1 0.2485 1.25
Nitrogen Dioxide NO2 0.74 0.1933 2.052 KR KR NO
Nitrogen Trifluoride NF3 0.48 0.1797 3.168
Nitrosyl Chloride NOCl 0.61 0.1632 2.92
Nitrous Oxide N2O 0.71 0.2088 1.964
Octafluorocyclobutane C4F8 0.17 0.185 8.397 Viton® KR
(Freon-C318)
Oxygen Difluoride OF2 0.63 0.1917 2.406
Oxygen O2 1 0.2193 1.427
Ozone O3 0.446 0.3 2.144
MoF6 0.21 0.1373 9.366
Viton®
Viton®
Viton®
Viton® Viton®
Viton® Viton®
Viton® Viton®
Viton®
Viton®
Viton® Viton®
Viton® Viton®
Viton® Viton®
Viton® Viton®
KR
KR
KR
KR
KR
NO
YES
NO
Page 46
Actual Gas Symbol (Cal/g) (g/l) @
Pentaborane B5H9 0.26 0.38 2.816
Pentane C5HI2 0.21 0.398 3.219
Perchloryl Fluoride CIO3F 0.39 0.1514 4.571
Perfluoropropane C3F8 0.174 0.197 8.388
Phosgene COCl2 0.44 0.1394 4.418
Phosphine PH3 0.76 0.2374 1.517
Phosphorous Oxychloride POCl3 0.36 0.1324 6.843
Phosphorous Pentafluoride PH5 0.3 0.161 5.62
Phosphorous Trichloride PCl5 0.3 0.125 6.127
Propane C3H8 0.36 0.3885 1.967
Propylene C3H6 0.41 0.3541 1.877
Silane SiH4 0.6 0.3189 1.433
Silicon Tetrachloride SiCl4 0.28 0.127 7.58
Silicon Tetrafluoride SiF4 0.35 0.1691 4.643
Sulfur Dioxide SO2 0.69 0.1488 2.858
Sulfur Hexafluoride SF6 0.26 0.1592 6.516
Sulfuryl Fluoride SO2F2 0.39 0.1543 4.562
Teos 0.09
Tetrafluorahydrazine N2F4 0.32 0.182 4.64
Trichlorofluormethane CCl3F 0.33 0.1357 6.129 Viton® KR
(Freon-11)
Trichlorisilane SiHCl3 0.33 0.138 6.043
1,1,2-Trichloro-1,2,2 CCl
Trifluorethane (Freon-113)
Trisobutyl Aluminum (C4H9)Al 0.061 0.508 8.848
Titanium Tetrachloride TiCl4 0.27 0.12 8.465
Trichloro Ethylene C2HCl3 0.32 0.163 5.95
Trimethylamine (CH3)3N 0.28 0.371 2.639
Tungsten Hexasfuoride WF6 0.25 0.081 13.28 KR Teflon
Uranium Hexafluoride UF6 0.2 0.0888 15.7
Vinyl Bromide CH2CHBr 0.46 0.1241 4.772
Vinyl Chloride CH2CHCl 0.48 0.12054 2.788
Xenon Xe 1.44 0.0378 5.858
Chemical K-factor
Relative
N2
FCClF2 0.2 0.161 8.36
2
Cp Density Elastomer* Nylon
O-ring Valve Compatible
0°C
Seat
Viton®
Viton®
Viton®
Viton®
Viton®
Viton®
Viton®
Viton®
Viton®
Viton® Viton®
Viton® Viton®
Viton®
Viton®
Viton®
Viton®
Viton® Viton®
Viton®
KR KR
Viton®
Viton®
Viton®
Viton® Viton®
Viton®
Viton®
Viton®
Viton®
Viton®
Viton®
Viton®
Viton® Viton®
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
KR
Corrosive
Gas
Limited
Warranty
YES
YES
YES
Page 47
Series 820 Instruction Manual Appendix B
Appendix B 822/824 Product Specifications
Page 48
Page 49
Series 820 Instruction Manual Appendix C
Appendix C 822S/824S Product Specifications
Page 50
Page 51
Page 52
Series 820 Instruction Manual Appendix D
Appendix D 826/827 Product Specifications
Page 53
Page 54
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