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MT/T 781-1998 English PDF

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MT/T 781-1998: General technical condition for high-resolution automatic earth resistivity instrument
Status: Obsolete
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MT/T 781-1998English319 Add to Cart 3 days [Need to translate] General technical condition for high-resolution automatic earth resistivity instrument Obsolete MT/T 781-1998

Standard similar to MT/T 781-1998

MT/T 1145   MT/T 1144   

Basic data

Standard ID MT/T 781-1998 (MT/T781-1998)
Description (Translated English) General technical condition for high-resolution automatic earth resistivity instrument
Sector / Industry Coal Industry Standard (Recommended)
Classification of Chinese Standard D82
Classification of International Standard 73.100.99
Word Count Estimation 8,827
Date of Issue 11/10/1998
Date of Implementation 4/1/1999

MT/T 7:

---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
General technical condition for high-resolution automatic earth resistivity instrument People's Republic of China Coal Industry Standard General technical specifications of high-resolution automatic ground resistivity meter General technical condition for high-resolution automatic earth resistivity instrument 1998-11-10 Approved.1999-04-01 Implementation Approved by State Coal Industry Bureau

Contents

Foreword Ⅱ 1 Scope 1 2 Normative references 1 3 Technical requirements 1 4 Test method 2 5 Inspection rules 3 6 Marking, packaging, transportation and storage 4

Foreword

This standard is proposed by the Industry Management Department of the State Coal Industry Bureau. This standard is under the jurisdiction of the Standardization Technical Committee for Special Equipment of Coal Industry and Coal Mine This standard was drafted by the Xi'an Branch of the General Research Institute of Coal Science. The main drafters of this standard. Jia Shengmao, Cao Yinsan. This standard entrusts the Xi'an Branch of the General Research Institute of Coal Science to be responsible for interpretation. General technical specifications of high-resolution automatic ground resistivity meter

1 Scope

This standard specifies the technical requirements, test methods, inspection rules, marking, packaging, transportation and storage of high-resolution automatic resistivity meters. This standard applies to high-resolution automatic resistivity meters (hereinafter referred to as instruments) used in field surveys.

2 Reference standards

The following standards contain provisions that, through reference in this standard, constitute provisions of this standard. When this standard was published, the editions shown were all Is effective. All standards will be revised, and all parties using this standard should explore the possibility of using the latest versions of the following standards. GB 191-1990 packing storage and transportation pictogram GB/T 6587.1-1986 General Outline of Environmental Testing for Electronic Measuring Instruments GB/T 6587.2-1986 temperature test of electronic measuring instrument GB/T 6587.3-1986 humidity test for electronic measuring instruments GB/T 6587.4-1986 vibration test of electronic measuring instrument GB/T 6587.5-1986 Impact test of electronic measuring instruments GB/T 6587.6-1986 transport test of electronic measuring instruments GB/T 6587.7-1986 Basic safety test for electronic measuring instruments GB/T 10111-1991 Random sampling method using random number dice GB/T 13384-1992 general technical requirements for packaging of mechanical and electrical products MT 210-1990 Basic test methods for electric and electronic products for communication, detection and control in coal mines

3 Technical requirements

3.1 General requirements The instrument shall meet the requirements of this standard and be manufactured in accordance with the drawings and documents approved by the prescribed procedures. 3.2 Composition The instrument consists of a transmitter, a receiver, and a power source. 3.3 Environmental conditions 3.3.1 The instrument should work normally under the following conditions. a) Ambient temperature. -10 ~ 40 ℃; b) Average relative humidity. less than 90% (25 ℃); c) Atmospheric pressure. 80 ~ 106 kPa; d) The surrounding environment shall be free of conductive and explosive gases and dust, and gases and vapors that may corrode metal parts and damage insulation. 3.3.2 The worst storage and transportation conditions that the instrument can withstand are. a) High temperature. 70 ℃; b) Low temperature. -40 ℃; c) Vibration. acceleration 20 m/s2; d) Shock. Peak acceleration 500 m/s2. 3.4 Electrical performance 3.4.1 Transmitter 3.4.1.1 Working frequency. 2 ~ 30 Set no less than three point frequencies in Hz, as specified by product standards. 3.4.1.2 Frequency stability. Guaranteed by temperature compensated crystal or other means, it should not be lower than 5 × 10-6. 3.4.1.3 The maximum supply current is not less than 1.5 A, and has over-current, short-circuit protection. 3.4.1.4 The transmitter shall have the function of automatic conversion of electrode power supply during measurement. 3.4.2 Receiver 3.4.2.1 Working frequency. It must correspond to the operating point frequency of the transmitter. 3.4.2.2 Inlet dynamic range. 10 μV ~ 2 V, but sensitivity must not be less than 100 μV. 3.4.2.3 Inlet equivalent noise. not more than 1 μV. 3.4.2.4 Suppression of maximum irrelevant level. 104. 3.4.2.5 Gain. 5 × 100 ~ 5 × 109, control in several steps. 3.4.3 Power supply. should not be less than 1.5 kW single phase 50 Hz, 220 V generator set provided. Can also take other reasonable power supply the way. 3.5 Structure and appearance 3.5.1 All screws and nuts must be tightened to prevent them from falling off automatically and vibration. 3.5.2 The appearance of the instrument must not be scratched, sunken or deformed. The enclosure shall have anti-rust measures. 3.6 Electrical safety The instrument must be leak-proof. Its insulation resistance, working voltage, leakage current, etc. must meet the requirements of normal work and personal safety. Claim. 3.7 Craft Transformer rectifier power supply, printed circuit boards, etc. should be taken to prevent moisture, mildew, and insulation. 3.8 Environmental adaptability 3.8.1 The instrument should be able to withstand the high and low temperature working tests performed under the conditions specified in Table 1, and meet the requirements of 3.4. 3.8.2 The instrument should be able to withstand the high and low temperature storage tests performed under the conditions specified in Table 1.After the test under normal atmospheric conditions, it should meet 3.4 requirements. 3.8.3 The instrument should be able to withstand the humidity test under the conditions specified in Table 1. After the test, the instrument should be able to work normally. Table 1 Test item temperature ℃ Test time h Recovery time Low temperature work test-10 2 Low temperature storage test -40 16 2 High temperature work test 40 2 High temperature storage test 70 16 2 Humidity test 40 ℃, 90% RH 48 3.8.4 The instrument should be able to withstand GB/T After the test, the instrument should be able to work normally. No obvious damage to the appearance. 3.8.5 The instrument should be able to withstand GB/T After the test, the instrument should be able to work normally. No obvious damage to the appearance. 3.8.6 The instrument should be able to withstand GB/T after packaging 6587.6-1986 in the transport test specified in Group III conditions, there should be no obvious packaging after the test Damaged, the instrument should be able to work normally without obvious damage to the casing.

4 Test method

4.1 Test conditions Unless otherwise specified in the environmental test or relevant standards, the test is performed under the following conditions. a) Temperature. 15 ~ 35 ℃; b) Relative humidity. 45% ~ 75%; c) Atmospheric pressure. 86 ~ 106 kPa. 4.2 Electrical performance test 4.2.1 Connect the dummy load indoors without opening the case. 4.2.2 The test block diagram is as follows. 4.2.3 The technical specifications of the test equipment should be compatible with the technical specifications of the instrument, and the precision should be an order of magnitude higher than the measured parameters. 4.3 Temperature test Instrument according to GB/T 6587.2-1986 group III conditions for temperature test. 4.4 Humidity test Instrument according to GB/T Humidity test was performed in Group Ⅲ conditions of 6587.3-1986. 4.5 Vibration test Instrument according to GB/T 6587.4-1986 group III conditions for vibration test. 4.6 Impact test Instrument according to GB/T 6587.5-1986 group III conditions for impact test. 4.7 Transport test After the instrument is packed, press GB/T 6587.6-1986 group III conditions for transportation test. 4.8 Basic safety test Instrument according to GB/T The requirements of 6587.7 for basic safety tests should include three aspects of insulation resistance, voltage, and leakage current. content. 4.9 Visual and structural inspection Press MT The provisions of Chapter 5 of 210-1990 are carried out.

5 Inspection rules

5.1 Factory inspection 5.1.1 Each product must undergo factory inspection by the inspection department of the manufacturer. Qualified products shall be issued with a product certificate. 5.1.2 The inspection items are carried out according to the contents of the factory inspection listed in Table 2. 5.2 Type inspection 5.2.1 Type inspection should be carried out in one of the following situations. a) When new products are trial-prototyped or old products are transferred to production; b) If the structure, materials, and processes have changed significantly after the official production, which may affect the product performance c) When production resumes after 1 year of suspension; d) at normal production for 3 years; e) when the quality of the product is unstable; f) When the national product quality inspection agency requests a type inspection. 5.2.2 The inspection items are carried out according to the type inspection contents listed in Table 2. Table 2 Inspection item requirements category test method factory inspection type inspection Appearance, structure, technology 3.5, 3.7 C 4.9 √ √ Electrical performance 3.4 A 4.2 √ √ High temperature operation 3.8.1 B 4.3 √ √ High temperature storage 3.8.2 B 4.3 × √ Low temperature operation 3.8.1 B 4.3 × √ Low temperature storage 3.8.2 B 4.3 × √ Damp heat 3.8.3 B 4.4 × √ Vibration 3.8.4 B 4.5 × √ Impact 3.8.5 B 4.6 × √ Transport 3.8.6 B 4.7 × √ Power frequency withstand voltage 3.6 A 4.8 √ √ Insulation resistance 3.6 A 4.8 √ √ Note. The column with “√” in the table indicates the items that must be tested, and “×” means no items. 5.2.3 One type shall be randomly selected from the qualified products during the factory inspection according to GB/T 10111. 5.2.4 Inspection and judgment rules. a) For a category A project, if one item fails, the batch is judged to be unqualified. b) For Category B items, if there are two unqualified items, the sampling inspection shall be doubled. If there are still two unqualified items, the product shall be deemed unqualified. c) For category C projects, the reference project for inspection shall be determined according to the situation. 6 Marking, packaging, transportation and storage 6.1 Signs 6.1.1 The product shall be provided with a nameplate, which shall include. a) Product name and model; b) the name of the manufacturer; c) main technical parameters; d) Date of manufacture and product number. 6.1.2 Packaging, storage and transportation marks shall comply with GB Regulation 191. 6.2 Packaging 6.2.1 Product packaging should comply with GB/T The requirements of 13384, specific packaging methods are stipulated by product standards. 6.2.2 Random documents should be attached when packing.The random documents include. a) product certification; b) instruction manual; c) packing list; d) other technical documents specified in the product standard. 6.3 Transport 6.3.1 The packaged product can be suitable for various transportation such as water, land and air transportation under the condition that it is not directly affected by rain and snow the way. 6.3.2 During transportation, avoid strong vibration and prevent falling. 6.4 Storage The product should be stored at a temperature of -10 ~ 40 In a well-ventilated warehouse at ℃, it should be checked regularly for long-term storage.

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