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JJG 291-2018 English PDF (JJG291-2008, JJG291-1999)

JJG 291-2018_English: PDF (JJG291-2018)
Standard IDContents [version]USDSTEP2[PDF] delivered inStandard Title (Description)StatusPDF
JJG 291-2018English439 Add to Cart 4 days [Need to translate] Dissolved Oxygen Meters Valid JJG 291-2018
JJG 291-2008English170 Add to Cart 0--9 seconds. Auto-delivery Verification regulation of dissolved oxygen meter with covered-membrane-electrode Obsolete JJG 291-2008
JJG 291-1999English479 Add to Cart 4 days [Need to translate] Verification Regulation of Film Electrode Dissolved Oxygen Meter Obsolete JJG 291-1999
JJG 291-1982EnglishRFQ ASK 3 days [Need to translate] (Chinese Industry Standard) Obsolete JJG 291-1982


BASIC DATA
Standard ID JJG 291-2018 (JJG291-2018)
Description (Translated English) Dissolved Oxygen Meters
Sector / Industry Metrology & Measurement Industry Standard
Word Count Estimation 19,130
Date of Issue 2018-02-27
Date of Implementation 2018-08-27
Older Standard (superseded by this standard) JJG 291-2008
Drafting Organization Zhejiang Institute of Metrology, Shanghai Institute of Metrology and Testing Technology
Administrative Organization National Environmental Chemometrics Technical Committee
Regulation (derived from) AQSIQ Announcement No. 26 of 2018
Issuing agency(ies) State Administration of Quality Supervision, Inspection and Quarantine

BASIC DATA
Standard ID JJG 291-2008 (JJG291-2008)
Description (Translated English) Verification regulation of dissolved oxygen meter with covered-membrane-electrode
Sector / Industry Metrology & Measurement Industry Standard
Classification of Chinese Standard A61
Classification of International Standard 17.020
Word Count Estimation 16,131
Date of Issue 2008-12-23
Date of Implementation 2009-06-23
Older Standard (superseded by this standard) JJG 291-1999
Drafting Organization Zhejiang Institute of Standardization
Administrative Organization National Technical Committee on Environment stoichiometric
Regulation (derived from) ?AQSIQ Announcement 2008 No.143
Issuing agency(ies) State Administration of Quality Supervision, Inspection and Quarantine
Summary This standard applies to real-time measurement of body surface potential heart-analog single-channel, multi-channel ECG initial verification and subsequent verification, This procedure does not apply to digital ECG machine, vector ECG, ECG and other nonlinear systems and ECG information processing and measuring instruments for special purposes.

BASIC DATA
Standard ID JJG 291-1999 (JJG291-1999)
Description (Translated English) Verification Regulation of Film Electrode Dissolved Oxygen Meter
Sector / Industry Metrology & Measurement Industry Standard
Classification of Chinese Standard A61
Word Count Estimation 12,166
Date of Issue 1999/6/21
Date of Implementation 2000/3/15
Older Standard (superseded by this standard) JJG 291-1982
Regulation (derived from) National AQSIQ Notice 2008 No. 143


JJG 291-2018 (Dissolved Oxygen Tester Verification Procedure) National Metrology Verification Regulations of the People's Republic Dissolved oxygen analyzer Published on.2018-02-27 2018-08-27 implementation The General Administration of Quality Supervision, Inspection and Quarantine issued Dissolved oxygen analyzer calibration procedures Replace JJG 291-2008 Focal Point. National Environmental Chemometrics Technical Committee Main drafting unit. Zhejiang Institute of Metrology Shanghai Institute of Metrology and Testing Technology Participated in the drafting unit. China Institute of Metrology Beijing Aerospace Measurement and Testing Technology Research Institute Foshan Analyzer Co., Ltd. This procedure entrusts the National Environmental Chemometrics Technical Committee to explain The main drafters of this procedure. Lin Wei (Zhejiang Institute of Metrology) Xu Yuan (Zhejiang Institute of Metrology) Wang Zhentao (Shanghai Institute of Metrology and Testing Technology) Participate in the drafters. Xiu Hongyu (China Institute of Metrology) Zhang Wei (Zhejiang Institute of Metrology) Fu Jiale (Shanghai Institute of Metrology and Testing Technology) Feng Zhijun (Beijing Aerospace Measurement and Testing Technology Research Institute) table of Contents Introduction (III) 1 range (1) 2 Overview (1) 3 Metrological performance requirements (1) 3.1 Zero error (1) 3.2 Response time (1) 3.3 Dissolved oxygen concentration indication error (1) 3.4 Repeatability (1) 3.5 Temperature indication error (1) 3.6 Salinity compensation error (1) 4 General technical requirements (1) 4.1 Appearance and Structure (1) 4.2 Signs and logos (1) 5 measuring instrument control (2) 5.1 Verification conditions (2) 5.2 Verification project (2) 5.3 Verification method (3) 5.4 Processing of verification results (4) 5.5 Verification cycle (5) Appendix A Preparation of certified water (6) Appendix B Preparation and verification water device structure diagram (7) Appendix C Oxygen saturation concentration in water at different water temperatures and atmospheric pressures and interpolation method to calculate saturated dissolved oxygen concentration in water (8) Appendix D Dissolved Oxygen Analyzer Verification Record (11) Appendix E Format of the verification certificate/verification result notice (13) introduction This procedure refers to HJ506-2009 "Electrochemical Probe Method for Determination of Dissolved Oxygen in Water", ISO 5814. 2012 Water Quality-Determinationof dissolvedoxygen-Electrochemicalprobemethod), ISO 17289.2014 "Water Dissolved Oxygen Water quality-Determination of dissolved oxygen-Opticalsensor Method) and other standards related content, according to JJF1002-2010 "National Metrology Verification Procedures Writing Rules" Written, compared with JJG 291-2008, in addition to editorial changes, the main content changes are as follows. --- Added introduction content; --- Revised the name of the procedure and the scope of application (see cover and scope 1); ---In the overview section, the measurement principle of the coated electrode dissolved oxygen analyzer and the fluorescent dissolved oxygen analyzer is added. Said (see 2 for an overview); --- Modified the "repetitive" metrology performance requirements (see 3.4); --- Removed "insulation resistance" and "insulation strength" technical requirements, verification items, equipment for verification and verification Method (see 4, 5.1, 5.2, 5.3); --- Modify the technical indicators such as the barometer index value in the standard and supporting equipment for verification, and increase the sodium chloride (NaCl) reagent purity requirements (see 5.1.2); --- Modified the "zero value error" verification method, extending the test time from "5min" to "15min", repair Changed the "response time" verification method (see 5.3.3, 5.3.4); --- Change the reference value of dissolved oxygen concentration to look-up table and interpolation method (see 5.3.5); --- Removed the "Saturation of Concentration Table of Oxygen at Different Temperatures" appendix in the original procedure and "Pure water at different temperatures" "Saturated Vapor Pressure" appendix adds "saturated concentration of oxygen in water at different water temperatures and atmospheric pressures" "Appendix" (see Appendix C). The previous versions of this procedure are released. ---JJG 291-2008; ---JJG 291-1999. Dissolved oxygen analyzer calibration procedures 1 Scope This procedure applies to benchtop and portable dissolved oxygen meters with a measurement range of (0~20) mg/L (see below) The first verification, subsequent verification and in-use inspection of the instrument. 2 Overview The instrument is primarily used to determine the concentration of dissolved oxygen (DO) in water. The instrument type mainly has a film electrode dissolved Oxygen analyzer and fluorescence dissolved oxygen meter. The measuring principle of the coated electrode dissolved oxygen analyzer is the electrochemical probe method. the oxygen sensitive membrane electrode is used to isolate water and Soluble matter, the potential difference between the electrodes causes the metal ions to enter the solution at the anode, while the oxygen diffuses through the membrane. Dispersed, reduced at the cathode, and the current produced is proportional to the rate of oxygen transmission through the membrane and electrolyte layer, ie at a certain The current is proportional to the partial pressure (or concentration) of oxygen in the water. Dissolved oxygen in water by measuring current concentration. The measurement principle of the fluorescent dissolved oxygen analyzer is mainly based on the quenching effect of oxygen molecules on fluorescent substances. in dissolution The electrode of the oxygen analyzer is coated with a fluorescent material, and the excitation light is irradiated on the electrode to emit fluorescence, and the fluorescence intensity or annihilation time is long. Short is related to the concentration of oxygen molecules in water; the higher the concentration of oxygen molecules in water, the smaller the fluorescence intensity, and the more annihilated fast. The dissolved oxygen concentration in the water can be obtained by measuring the phase difference between the excitation light and the reference light. The instrument typically consists of an oxygen electrode, an electronic unit, and/or a display unit. 3 Metrological performance requirements 3.1 Zero value error The zero value error of the instrument should not exceed 0.10mg/L. 3.2 Response time The response time of the instrument should not exceed 60s. 3.3 Dissolved oxygen concentration indication error The initial error of the dissolved oxygen concentration indication error of the instrument should not exceed ±0.30mg/L, and the subsequent verification should not exceed Over ±0.50mg/L. 3.4 Repeatability The repeatability of the instrument should not exceed 0.15 mg/L. 3.5 Temperature indication error The temperature indication error of the instrument should not exceed ±0.5 °C. 3.6 Salinity compensation error The salinity compensation error of the instrument should not exceed ±2%. 4 General technical requirements 4.1 Appearance and structure ......


JJG 291-2008 JJF National Metrology Technical Specifications of the People's Republic of China Dissolved Oxygen Meter with Covered-Membrane- Electrode ISSUED ON. DECEMBER 23, 2008 IMPLEMENTED ON. JUNE 23, 2009 Issued by. State Administration for Quality Supervision and Inspection and Quarantine Verification Regulation of Dissolved Oxygen Meter with Covered-Membrane-Electrode Replacing JJG 291-1999 This regulation was approved by General Administration of Quality Supervision, Inspection and Quarantine on December 23, 2008 and shall be implemented from June 23, 2009. Jurisdictional organization. National Technical Committee on Environmental Stoichiometry Drafting organization. Zhejiang Province Institute of Metrology This regulation is entrusted to and shall be responsibly interpreted by National Technical Committee on Environmental Stoichiometry. Drafter of this regulation. Zhang Yanqun (Zhejiang Province Institute of Metrology) Table of Contents 1 Scope ... 5  2 Overview ... 5  3 Requirements for metrological performance ... 5  4 General technical requirements ... 5  5 Measuring instrument control ... 6  Annex A Preparation of Water for Verification ... 13  Annex B Structural Drawing of Device for Verification Water Preparation ... 14  Annex C Saturation concentration table of oxygen in water with different temperatures  ... 15  Annex D Saturated Vapor Pressure of Pure Water at Different Temperatures... 16  Annex E Verification Record ... 17  Annex F Format of Verification Certificate and Note of Verification Result ... 19  (Inner Page) ... 19  Dissolved Oxygen Meter with Covered-Membrane-Electrode 1 Scope This regulation applies to initial verification, subsequent verification and in-use verification of laboratory-service and portable dissolved oxygen meters with covered-membrane-electrode (hereinafter referred to as the instrument) that have a measuring range of (0 ~ 20)mg/L. 2 Overview The instrument is used to measure concentration of constant dissolved oxygen meter (DO) in water. The instrument is composed of covered-membrane-oxygen electrode, electronic unit and displayer. 3 Requirements for metrological performance 3.1 Zero error Zero error of instrument shall not exceed 0.10 mg/L. 3.2 Response time Response time of instrument shall not exceed 60 s. 3.3 Dissolved oxygen concentration indication error Dissolved oxygen concentration indication error of instrument for initial verification shall not exceed ±0. 30 mg/L; indication error for subsequent verification shall not exceed ±0. 50 mg/L. 3.4 Repeatability Standard deviation of instrument for initial verification shall not exceed 0.15 mg/L; standard deviation for subsequent verification shall not exceed 0.20 mg/L. 3.5 Temperature indication error Temperature indication error of instrument shall not exceed ± 0. 5°C. 3.6 Salinity compensation error Salinity compensation error of instrument shall not exceed ± 2 %. 4 General technical requirements 4.1 Appearance 4.1.1 The instrument shall indicate the name of manufacturing company, model and manufacturing number; domestic instrument shall be marked with metering equipment referring to Annex D, in Pa. Take △c with maximum absolute value as dissolved oxygen concentration indication error. 5.3.7 Verification of repeatability 5.3.7.1 Verification of repeatability of instrument shall be carried out in saturated dissolved oxygen water that thermostatic water batch is close to the room temperature. 5.3.7.2 Measure table saturated dissolved oxygen water for continuous 6 times; record 5.3 Verification method 5.3.1 Appearance Check through vision or hand feeling according to requirements of 4.1. 5.3.2 Verification of insulation resistance The instrument is not connected to power source. Turn on the power switch. Connect one end of insulation resistance meter to the phase of instrument input terminal and neutral conjunction line, while connect the other end to protective earth terminal (or shell) of the instrument. Apply test voltage of 500 V and continue for 5 s; measure insulation resistance. 5.3.3 Verification of dielectric strength The instrument is not connected to power source. Turn on the power switch. Connect two measuring lines of dielectric strength tester to phase of power input terminal, central conjunction line and ground terminal (or shell). Apply test voltage of 1 500 V; set leak current to be 5 mA and lifting time to be (5s to 20)s; keep for 1 min, and then lower the voltage to 0 V stably. There shall be no breakdown and arcing phenomena during the test process. 5.3.4 Verification zero error 5.3.4.1 Calibrate normally according to the requirements of operation instruction of instrument. 5.3.4.2 Immerse electrode into freshly prepared oxygen-free solution at a temperature of (20±5)°C from air; see A.1 in Annex A for preparation of anaerobic water. 5.3.4.3 Instrument indication after 5 min is just the zero error caused by zero bit current. 5.3.5 Verification of response time 5.3.5.1 Control thermostatic water bath temperature to (20±1)°C; prepare saturated dissolved oxygen water according to requirements in A.2 of Annex A. 5.3.5.2 Take electrode out of thermostatic water bath and immerse into oxygen-free water quickly; meanwhile start timing. 5.3.5.3 Stop timing when the instrument displays 90% stable value; the reading of stopwatch is just the response time. 5.3.6 Verification of dissolved oxygen concentration indication error 5.3.6.1 Re-calibrate the instrument. instrument according to Formula (4). )4...(...si  Where, Ti - Instrument indication temperature value, in °C; Ts - Reading of precision thermometer, in °C. Take △T with maximum absolute value as instrument temperature indication error of instrument. 5.3.9 Verification of salinity compensation error 5.3.9.1 Pour 1 L of distilled water into the beaker; place it into thermostatic water bath at a temperature of (15±0.2)°C; stop bubbling 1 h after the start; still for 10 min and measure concentration N0 of dissolved oxygen concentration with zero salt. Standard value of water dissolved oxygen concentration that salt content is n(g/L) is obtained according to Formula (5). )5...(...9055.0-0sn nNN  Where, n - Salt (NaCl) in grams, n may be 10g, 20g and 30g. Note. 0.055 9 refers to the variation of solubility when water temperature is 15°C and salt content is 1 g/L (△Cs). See Annex A of GB/T 11913- 1989. 5.3.9.2 Maintain pure water temperature 15°C; add salt of 10 g and stir uniformly; prepare it to be saturated dissolved oxygen water that salt content is 10 g/L and measure to get N10 (measure for 2 times and take the average value). Use the same method to prepare water into saturated dissolved oxygen water that salt content is 20, 30 g/L and measure to get N20 and N30 respectively. Calculate salinity compensation error according to Formula (6). ߂ܰ ൌ ܰ௡ିܰ௦௡ܰୱ௡ ൈ 100% ... (6) Where, Nn - Concentration of saline dissolved oxygen, which may be N10, N20, N30, in mg/L. Take the △N with the maximum absolute value as salinity compensation error of instrument. 5.4 Verification results handling 5.4.1 In case of poor electrode performance discovered during verification process, it is allowed to replace electrode electrolyte and membrane; re-verification is required after the replacement. 5.4.2 Issue verification qualification certificate for instruments that are verified qualified according to this regulation. For disqualified instruments, issue notice of verification results, Annex F Format of Verification Certificate and Note of Verification Result (Inner Page) F.1 Format of verification certificate (inner pages) Verification Item Technical Requirements Verification Results Appearance Zero error Insulation resistance Dielectric strength Response time Dissolved oxygen concentration indication error Repeatability Temperature indication error Salinity compensation error F.2 Format of notice of verification result (inner pages) Verification Item Technical Requirements Technical Results Conclusion of Single Item Appearance Insulation resistance Dielectric strength Zero error Response time Dissolved oxygen indication error Repeatability Temperature indication error Salinity compensation error Disqualified item. ......

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