SierraメーカーINNOVA-MASS 240-VTの使用説明書/サービス説明書
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Series 24-HP Instruction Manual Table of Contents IM-24-HP 0-1 Sierra Series 240 and 241 Innova-Mass™ Multi-Parameter V ortex Mass Flow Meters Models 240-VT , 240-VTP , 241-VT , 241-VTP Instruction Manual Part Number: IM-24-HP, Rev.
Table of Contents Series 24-HP Instruction Manual 0-2 IM-24-HP Customer Notice Unless you have specifically ordered Sierra’s optional O 2 cleaning, this flow meter may not be fit for oxygen service.
Series 24-HP Instruction Manual Table of Contents IM-24-HP 0-3 Table of Contents Chapter 1 Introduction Innova-Mass™ Vortex Mass Flow Meters .......................................... 1-1 Using this Manual ...........................................
Table of Contents Series 24-HP Instruction Manual 0-4 IM-24-HP Energy Menu ....................................................................... 3-10 Fluid Menu .................................................................................. 3-11 Units Menu .
Series 24-HP Instruction Manual Table of Contents IM-24-HP 0-5 Figures 1-1. In-Line Vortex Multi-Parameter Mass Flow Meter ................ 1-3 1-2. Measurement Principle of Vortex Flow Meters ...................... 1-4 1-3. Reynolds Number Range of the Innova-Mass .
Table of Contents Series 24-HP Instruction Manual 0-6 IM-24-HP Warnings and Cautions Warning! Agency approval for hazardous location installations varies between flow meter models. Consult the flow meter nameplate for specif ic flow meter approvals before any hazardous location installation.
Series 24-HP Instruction Manual Chapter 1 Introduction IM-24-HP 1-1 Chapter 1 Introduction Innova-Mass ™ Multi-Parameter V ortex Mass Flow Meters The Sierra Instruments’ Series 240 In-Line and the Series 241 Insertion Innova-Mass™ Vortex Flow Meters provide a reliable solution for process flow measurement.
Chapter 1 Introduction Series 24-HP Instruction Manual 1-2 IM-24-HP Note and Safety Information We use note, caution and warning statements throughout this book to draw your attention to important information. Warning! Caution! Note This statement appears with information that is important to protect people and equipment from damage.
Series 24-HP Instruction Manual Chapter 1 Introduction IM-24-HP 1-3 How the Innova-Mass V ortex Mass Flow Meter Operates Figure 1-1. In-Line Vortex Mu lti-Parameter Mass Flow Meter Sierra Series 240 a.
Chapter 1 Introduction Series 24-HP Instruction Manual 1-4 IM-24-HP Vortex Shedding Frequency Von Karman vortices form downstream of a shedder bar into two distinct wakes. The vortices of one wake rotate clockwise while those of the oth- er wake rotate counterclockwise.
Series 24-HP Instruction Manual Chapter 1 Introduction IM-24-HP 1-5 Re = ρ V D μ St = f d V Flow Velocity Range To ensure trouble-free operation, vorte x flow meters must be correctly sized so that the flow velocity range through the meter lies within the measurable velocity range (with acceptable pressure drop) and the linear range.
Chapter 1 Introduction Series 24-HP Instruction Manual 1-6 IM-24-HP As shown in Figure 1-3, Innova-M ass™ meters exhibit a constant Strouhal number across a large range of Reynolds numbers, indicating a consistent linear output over a wide ra nge of flows and fluid types.
Series 24-HP Instruction Manual Chapter 1 Introduction IM-24-HP 1-7 Pressure Measurement Innova-Mass Flow Meters incorporate a solid-state pressure transducer isolated by a 316 stainless steel diaphragm. The transducer itself is mi- cro-machined silicon, fabricated using integrated circuit processing tech- nology.
Chapter 1 Introduction Series 24-HP Instruction Manual 1-8 IM-24-HP Flow Meter Electronics Innova-Mass Flow Meter electronics are available mounted directly to the flow body, or remotely mounted. The electronics housing may be used indoors or outdoors, including wet environments.
Series 24-HP Instruction Manual Chapter 2 Installation IM-24-HP 2-1 Chapter 2 Installation Installation Overview Sierra’s Innova-Mass Vortex Flow Meter installations are simple and straightforward. Both the Series 240 In-Line and Series 241 Insertion type flow meter installations are covered in this chapter.
Chapter 2 Installation Series 24-HP Instruction Manual 2-2 IM-24-HP Unobstructed Flow Requirements Select an installation site that will minimize possible distortion in the flow profile. Valves, elbows, control valves and other piping components may cause flow disturbances.
Series 24-HP Instruction Manual Chapter 2 Installation IM-24-HP 2-3 Series 240 In-Line Flow Meter Installation Install the Series 240 In-Line Flow Me ter between two conventional pipe flanges as shown in Figures 2-3 and 2-4.
Chapter 2 Installation Series 24-HP Instruction Manual 2-4 IM-24-HP Wafer-Style Flow Meter Installation Install the wafer-style meter between two conventional pipe flanges of the same nominal size as the flow m eter. If the process fluid is a liquid, make sure the meter is located where the pi pe is always full.
Series 24-HP Instruction Manual Chapter 2 Installation IM-24-HP 2-5 Flange-Style Flow Meter Installation Install the flange-style meter between two conventional pipe flanges of the same nominal size as the flow m eter. If the process fluid is a liquid, make sure the meter is located where the pipe is always full.
Chapter 2 Installation Series 24-HP Instruction Manual 2-6 IM-24-HP Series 241 Insertion Flow Meter Installation Prepare the pipeline for installation using either a cold tap or hot tap me- thod described on the following pages. Refer to a standard code for all pipe tapping operations.
Series 24-HP Instruction Manual Chapter 2 Installation IM-24-HP 2-7 Cold Tap Guidelines Refer to a standard code for all pipe tapping operations. The following tapping instructions are general in nature and intended for guideline pur- poses only. 1. Turn off the flow of process gas, liquid or steam.
Chapter 2 Installation Series 24-HP Instruction Manual 2-8 IM-24-HP Hot Tap Guidelines Refer to a standard code for all pipe tapping operations. The following tapping instructions are general in nature and intended for guideline pur- poses only.
Series 24-HP Instruction Manual Chapter 2 Installation IM-24-HP 2-9 Flow Meter Insertion The sensor head must be properly positioned in the pipe. For this reason, it is important that insertion length calculations are carefully followed. A sensor probe inserted at the wrong depth in the pipe will result in inaccu- rate readings.
Chapter 2 Installation Series 24-HP Instruction Manual 2-10 IM-24-HP Installing Flow Meters with a Compression Connection* Use the following formula to determine insertion length for flow m eters (NPT and flanged) with a compression process connection.
Series 24-HP Instruction Manual Chapter 2 Installation IM-24-HP 2-11 Insertion Procedure for Meters with a Compression Connection Figure 2-7. Flow Meter with Compression Type Fitting 1. Calculate the required sensor probe insertion length. 2. Fully retract the stem until the senso r head is touching the bottom of the stem housing.
Chapter 2 Installation Series 24-HP Instruction Manual 2-12 IM-24-HP Installing Flow Meters with a Packing Gland Connection* Use the formula below to determine the insertion depth for flow m eters (NPT and flanged) equipped with an in sertion tool. To install, see the next page for instructions for meters with a permanent insertion tool.
Series 24-HP Instruction Manual Chapter 2 Installation IM-24-HP 2-13 Insertion Procedure for Flow Meters with Permanent Insertion Tool Figure 2-9. Flow Meter with Permanent Insertion Tool 1. Calculate the required sensor probe insertion length (see previous page).
Chapter 2 Installation Series 24-HP Instruction Manual 2-14 IM-24-HP Insertion Procedure for Flow Meters with Removable Insertion Tool Figure 2-10. Flow Meter with Removable Insertion Tool 1.
Series 24-HP Instruction Manual Chapter 2 Installation IM-24-HP 2-15 7. Tighten the packing gland nuts to stop leakage around the stem. Do not torque over 20 ft-lbs. 8. Slide the stem clamp back into position. Torque stem clamp bolts to 15 ft-lbs. Replace the stem clamp nuts and torque to 10-15 ft-lbs.
Chapter 2 Installation Series 24-HP Instruction Manual 2-16 IM-24-HP Insertion Procedure for Flow Meters with No Insertion Tool (Packing Gland Connection) 1. Calculate the required sensor probe insertion length. 2. Fully retract the stem until the sensor head is touching the bottom of the stem housing.
Series 24-HP Instruction Manual Chapter 2 Installation IM-24-HP 2-17 Adjusting Meter Orientation Depending on installation requirements, you may need to adjust the meter orientation. There are two adjustments available. The first rotates the posi- tion of the LCD display/keypad and is available on both in-line and inser- tion meters.
Chapter 2 Installation Series 24-HP Instruction Manual 2-18 IM-24-HP Enclosure Adjustment (Series 240 Only) Figure 2-13. Enclosure Viewing Adjustment To avoid damage to the sensor wires, do not rotate the enclosure beyond 180-degrees from the original position.
Series 24-HP Instruction Manual Chapter 2 Installation IM-24-HP 2-19 Wiring Connections The NEMA 4X enclosure contains an integral wiring compartment with one dual strip terminal block (located in the smaller end of the enclo- sure). Two 3/4-inch female NPT conduit entries are available for sepa- rate power and signal wiring.
Chapter 2 Installation Series 24-HP Instruction Manual 2-20 IM-24-HP 4-20 mA Output Connections The standard Innova-Mass Flow Meter has a single 4-20 mA loop. Two additional loops are available on the optional communication board. The 4-20 mA loop current is controlled by the meter electronics.
Series 24-HP Instruction Manual Chapter 2 Installation IM-24-HP 2-21 Figure 2-18. Non-Isolated 4–20 mA Out put Using Meter Input Power Supply Figure 2-19. Isolated 4–20 mA Output using Meter Provided Power Supply Pulse Output Connections The pulse output is used for a remote counter.
Chapter 2 Installation Series 24-HP Instruction Manual 2-22 IM-24-HP Figure 2-20. Isolated Pulse Output with External Power Supply Figure 2-21. Non-Isolated Pulse Ou tput Using Input Power Supply Figure 2-22.
Series 24-HP Instruction Manual Chapter 2 Installation IM-24-HP 2-23 Alarm Output Connections One alarm output (Alarm 1) is included on the standard Innova-Mass™ Flow Meter. Two or more alarms (A larm 2 and Alarm 3) are included on the optional communication board.
Chapter 2 Installation Series 24-HP Instruction Manual 2-24 IM-24-HP Figure 2-25. Isolated Alarm Output Using Meter Provided Power Supply Remote Electronics Wiring The remote electronics enclosure should be mounted in a convenient, easy to reach location.
Series 24-HP Instruction Manual Chapter 2 Installation IM-24-HP 2-25 Optional Input Electronics Wiring The meter has two optional input wiring terminals.
Series 24-HP Instruction Manual Chapter 3 Operation IM-24-HP 3-1 Chapter 3 Operating Instructions After installing the Innova-Mass Vortex Flow Meter, you are ready to begin operation. The sections in this chapter explain the display/keypad commands, meter start-up and programm ing.
Chapter 3 Operation Series 24-HP Instruction Manual 3-2 IM-24-HP Setup Menus Password Mass Flow Rate Volum e Flow Rate Temperature Pressure Density Total Alarm 1 Status Fluid ENTER Date & Time Ala.
Series 24-HP Instruction Manual Chapter 3 Operation IM-24-HP 3-3 Using the Setup Menus Programming the Flow Meter 1. Enter the Setup Menu by pressing the ENTER key until prompted for a password. (All outputs are disabled while using the Setup Menus.) 2.
Chapter 3 Operation Series 24-HP Instruction Manual 3-4 IM-24-HP Output Menu.
Series 24-HP Instruction Manual Chapter 3 Operation IM-24-HP 3-5 Example for Setting an Output The following shows how to set Output 1 to measure m ass flow with 4 m A = 0 lb/hr and 20 mA = 100 lb/hr wi th a time const ant of 5 seconds. (All outputs are disabl ed while using the Setup Me nus.
Chapter 3 Operation Series 24-HP Instruction Manual 3-6 IM-24-HP Display Menu Password ENTER Use keys to access menus Display Menu Cycle Time(Sec) 0 ENTER Run Mode Number of Digits 2 MF Vf Te Pr De T .
Series 24-HP Instruction Manual Chapter 3 Operation IM-24-HP 3-7 Alarms Menu Example for Setting an Alarm The following shows how to set Alarm 1 to activate if the m ass flow rate is great er than 100 lb/hr. You can check the alarm configurat ion in the Run Mode by pressing t he ×Ø keys until Alarm [1] appears.
Chapter 3 Operation Series 24-HP Instruction Manual 3-8 IM-24-HP Totalizer #1 Menu Password ENTER Use keys to acces s menus Totali zer Menu Totaling Inactive Mass Volume ENTER Run Mode (unit)/Pulse xx.
Series 24-HP Instruction Manual Chapter 3 Operation IM-24-HP 3-9 Totalizer #2 Menu Password ENTER Use keys to acces s menus Totali zer Menu Totaling Inactive Mass Volume ENTER Run Mode Reset Total? YES or NO Energy Use the Totalizer #2 to Monitor Flow or Energy.
Chapter 3 Operation Series 24-HP Instruction Manual 3-10 IM-24-HP Energy Menu – For EMS Energy Meters Only Configuration: There are several possibilities regarding the measureme nt of water or steam energy given the location of the meter and the use of a second RTD.
Series 24-HP Instruction Manual Chapter 3 Operation IM-24-HP 3-11 Fluid Menu Password ENTER Use key s to ac ce ss menu s Fluid Menu Flowing Fluid Liqui ds > Goya l-Do rais > API 2540 > Nat Ga.
Chapter 3 Operation Series 24-HP Instruction Manual 3-12 IM-24-HP Units Menu Use the Units Menu to configure the flow meter with the desired units of measurem ent.
Series 24-HP Instruction Manual Chapter 3 Operation IM-24-HP 3-13 Time & Date Menu Pass word ENT ER Use keys to ac ce ss menus Tim e & Da te Menu Set T ime xx:xx:xx ENT ER Run Mode Set D ate xx/xx/xx Use the Time and Date Menu to enter the co rrect time and date into the flow m eter’s memory.
Chapter 3 Operation Series 24-HP Instruction Manual 3-14 IM-24-HP Diagnostics Menu Use the Diagnostics Menu to simulate operation and review the system files.
Series 24-HP Instruction Manual Chapter 3 Operation IM-24-HP 3-15 Calibration Menu The Calibration Menu contains the calibration co efficients for the flow meter. These values should by changed only by properly trained pe rsonnel. The Vortex Coef Ck and Low Flow Cutoff are set at the factory.
Chapter 3 Operation Series 24-HP Instruction Manual 3-16 IM-24-HP Password Menu Passw ord ENT ER Use keys to access m enus Passw ord Menu Set Passwor d 1234 ENT ER Run Mode Use the Password Menu to set or change the system password. The factory-set password is 1234.
Series 24-HP Instruction Manual Chapter 4 Troubleshooting & Repair IM-24-HP 4-1 Chapter 4 T roubleshooting and Repair Hidden Diagnostics Menus The menus shown to the left can be ac- cessed using the password 16363, then moving to the display that reads “Diagnos- tics Menu” and pressing ENTER (rather than one of the arrow keys).
Chapter 4 Troubleshooting & Repair Series 24-HP Instruction Manual 4-2 IM-24-HP Column One Hidden Diagnostics Values • f = vortex shedding frequency (Hz). • fi = adaptive filter – should be approximately 25% higher than the vortex shedding frequency, this is a low-pass filter.
Series 24-HP Instruction Manual Chapter 4 Troubleshooting & Repair IM-24-HP 4-3 must be below the Low Flow Cutoff setting or the m eter will have an output at no flow. • Adj. Flilter = adjustable filter. Displays the filtering in deci- bels. Normally reads zero.
Chapter 4 Troubleshooting & Repair Series 24-HP Instruction Manual 4-4 IM-24-HP • Alarm (3) Test = Used as a test to verify that the alarm circuit is functioning. When low is selected the alarm will initiate a low alarm on the output. When High is selected it will give a high alarm on the output.
Series 24-HP Instruction Manual Chapter 4 Troubleshooting & Repair IM-24-HP 4-5 o B = RTD coefficient B (-5.775e-07). o Slope = unique value for each set of electronics. o Int = unique value for each set of electronics. • RTD2 = Second RTD configuration, for special applications only.
Chapter 4 Troubleshooting & Repair Series 24-HP Instruction Manual 4-6 IM-24-HP Troubleshooting the Flow Meter Symptom: Output at no Flow 1. The low flow cutoff is set too low. At no flow, go to the first column of the hidden diagnostics menu and record the Lvl value.
Series 24-HP Instruction Manual Chapter 4 Troubleshooting & Repair IM-24-HP 4-7 setting. During flow, view the f and fi values in the first col- umn of the hidden diagnostics. The fi value should be approx- imately 10-20 % higher than the f value.
Chapter 4 Troubleshooting & Repair Series 24-HP Instruction Manual 4-8 IM-24-HP 3. Using ESD precautions and hazardous area precautions, re- move the electronics enclosure window cover.
Series 24-HP Instruction Manual Chapter 4 Troubleshooting & Repair IM-24-HP 4-9 1. Turn off power to the unit. 2. Locate and loosen the small set screw which locks the larger enclosure cover in place. Unscrew the cover to expose the elec- tronics stack.
Chapter 4 Troubleshooting & Repair Series 24-HP Instruction Manual 4-10 IM-24-HP 5. Reassemble in reverse order. Returning Equipment to the Factory Before returning any Innova-Mass flow meter to the factory, you must request a Return Material Authorization (RMA) number .
Series 24-HP Instruction Manual Appendix A Specifications IM-24-HP A-1 Appendix A Product Specifications Accuracy Process Variables 240 Series In-Line Meters 241 Series Insertion Meters (1) Liquids Gas & Steam Liquids Gas & Steam Mass Flow Rate ±1% of rate over a 30:1 range (3) ±1.
Appendix A Specifications Series 24-HP Instruction Manual A-2 IM-24-HP Nom inal Pipe Siz e (in) P r e s s u r e 0 . 5 0 . 7 5 1 1 . 5 23468 1.8 3 5 13 22 50 87 198 347 18 41 90 221 369 826 1437 3258 5.
Series 24-HP Instruction Manual Appendix A Specifications IM-24-HP A-3 Nom inal Pipe Siz e (in) P r e s s u r e 0 . 5 0 . 7 5 1 1 . 5 23468 6.5 12 20 49 82 183 318 722 1264 52 122 265 650 1087 2431 42.
Appendix A Specifications Series 24-HP Instruction Manual A-4 IM-24-HP 241 Pressure Ratings Probe Seal Process Connection Material Rating Ordering Code Compression Fitting 2-inch MNPT 316L SS ANSI 600.
Series 24-HP Instruction Manual Appendix A Specifications IM-24-HP A-5 Pocess Fluid and Process Fluid : Ambient Temperature Standard temperature sens or: –40° F to 500° F (–40° C to 260° C). High temperature sensor: to 750° F ( to 400° C). Ambient: Operating: –5° F to 140° F (–20° C to 60° C).
Series 24-HP Instruction Manual Appendix B Glossary IM-24-HP B-1 Appendix B Glossary A B C D A Cross sectional area. ACFM Actual Cubic Feet Per Mi nute (volumetric flow rate). ASME American Society of Mechanical Engineers. Bluff Body A non-streamlined body placed into a flow stream to create vortices.
Appendix B Glossary Series 24-HP Instruction Manual B-2 IM-24-HP I J K L In-Line Flow Meter A flow meter which includes a short section of piping which is put in-line with the user’s piping. Insertion Flow Meter A flow meter which is inserted into a hole in the us- er’s pipeline.
Series 24-HP Instruction Manual Appendix B Glossary IM-24-HP B-3 Q R S T Q Flow rate, usually volumetric. Rangeability Highest measurable flow rate divided by the lowest measurable flow rate.
Series 24-HP Instruction Manual Appendix C Fluid Calculations IM-24-HP C-1 Appendix C Fluid Calculations Calculations for Steam T & P When “Steam T & P” is selected in the “Real Gas” selection of the Fluid Menu, the calculations are based on the equations below.
Appendix C Fluid Calculations Series 24-HP Instruction Manual C-2 IM-24-HP Calculations for Gas (“Real Gas” and “Other Gas”) Use this formula to determine the settings for “Real Gas; Gas” selections and “Other Gas” selections entered in the Fluid Menu.
Series 24-HP Instruction Manual Appendix C Fluid Calculations IM-24-HP C-3 Calculations for Liquid Use this formula to determine the settings for “Goyal-Dorais” selections and “Other Liquid” selections entered in the Fluid Menu. The liquid cal- culations were taken from Richard W.
Series24-HP Instruction Manual Appendix D HART Commands IM-24-HP D-1 Appendix D HART Commands with DD Menu Online Menu 1 Device Setup 2 Process Variables 3 PV is 4 PV 5 AO1 Out 6 PV % rnge 7 Alrm Stat.
Appendix D HART Commands Series24-HP Instruction Manual D-2 IM-24-HP Appendix D HART Commands without DD Menu Online Menu 1 Device Setu p 2 PV 3 PV AO 4 PV LRV 5 URV 1 Process Variables 2 Diag/Servi c.
Appendix E MODBUS Commands Series 24-HP Instruction Manual IM-24-HP E-1 Appendix E Modbus Communication Applicable Flow Meter Models Sierra Innova-Mass® Mass Flow Meters, Models 240 and 241 with Modbus communication protocol and firmware version 3.00.
Appendix E MODBUS Commands Series 24-HP Instruction Manual E-2 IM-24-HP Modbus Units The Modbus Units menu is to control what units, where applicable, the meter’s variables will be displayed in.
Series 24-HP Instruction Manual Appendix E MODBUS Commands IM-24-HP E-3 there is an informal register numbering c onvention derived from the original (now obsolete) Modicon Modbus protocol spec ification, and used by many vendors of Modbus capable products.
Appendix E MODBUS Commands Series 24-HP Instruction Manual E-4 IM-24-HP gramming Output Menu’s “Modbus Un its” item. The display units strings may be examined by accessi ng their associated registers.
Series 24-HP Instruction Manual Appendix E MODBUS Commands IM-24-HP E-5 The following registers contain the display units strings: Registers Variable Data type Units Function code Addresses 32007-3201.
Appendix E MODBUS Commands Series 24-HP Instruction Manual E-6 IM-24-HP The status of the three alarms may be monitored via the Modbus Read Discrete Input command (function code 02). The value returned indicates the state of the alarm, and will be 1 only if the alarm is enabled and active.
Series 24-HP Instruction Manual Appendix E MODBUS Commands IM-24-HP E-7 The start address is equal to the desired first register number minus one. The addresses derived from the start address and the number of registers must all be mapped to valid defined registers, or an invalid data address exception will oc- cur.
Appendix E MODBUS Commands Series 24-HP Instruction Manual E-8 IM-24-HP ter definitions 01 04 18 00 00 03 E8 00 00 7A 02 6C 62 00 00 41 BA 87 F2 3E BF FC 6F 42 12 EC 8B 4D D1 01 Device address 04 Func.
Series 24-HP Instruction Manual Appendix E MODBUS Commands IM-24-HP E-9 The unit responds with an identical message to that transmitted, and the totalizer is reset. If the “coil” is tu rned off as in the following message, the response is al- so identical to the transmitted message, but the totalizer is not affected.
Sierra 24-HP Instruction Manual Appendix F ATEX-IECEx Specifications IM-24-HP F-1 Appendix F ATEX-IECEx Specifications NEN EN IEC 60079-0 (2004) Electrical Apparatus for explosive gas atmospheres Gene.
デバイスSierra INNOVA-MASS 240-VTの購入後に(又は購入する前であっても)重要なポイントは、説明書をよく読むことです。その単純な理由はいくつかあります:
Sierra INNOVA-MASS 240-VTをまだ購入していないなら、この製品の基本情報を理解する良い機会です。まずは上にある説明書の最初のページをご覧ください。そこにはSierra INNOVA-MASS 240-VTの技術情報の概要が記載されているはずです。デバイスがあなたのニーズを満たすかどうかは、ここで確認しましょう。Sierra INNOVA-MASS 240-VTの取扱説明書の次のページをよく読むことにより、製品の全機能やその取り扱いに関する情報を知ることができます。Sierra INNOVA-MASS 240-VTで得られた情報は、きっとあなたの購入の決断を手助けしてくれることでしょう。
Sierra INNOVA-MASS 240-VTを既にお持ちだが、まだ読んでいない場合は、上記の理由によりそれを行うべきです。そうすることにより機能を適切に使用しているか、又はSierra INNOVA-MASS 240-VTの不適切な取り扱いによりその寿命を短くする危険を犯していないかどうかを知ることができます。
ですが、ユーザガイドが果たす重要な役割の一つは、Sierra INNOVA-MASS 240-VTに関する問題の解決を支援することです。そこにはほとんどの場合、トラブルシューティング、すなわちSierra INNOVA-MASS 240-VTデバイスで最もよく起こりうる故障・不良とそれらの対処法についてのアドバイスを見つけることができるはずです。たとえ問題を解決できなかった場合でも、説明書にはカスタマー・サービスセンター又は最寄りのサービスセンターへの問い合わせ先等、次の対処法についての指示があるはずです。