1, IEC 60079-0: 2007 is adopted in the revision of the new standard, which is equivalent to IEC 60079-0: 1998 in the old standard.
2. The explosive dust standard system and the explosive gas standard system are combined. The original explosive gas environment is now explosive gas environment and explosive dust environment, and the standard name is changed from "explosive gas environment" to "explosive environment". At the same time, the requirements for explosive dust environment are added in the standard provisions.
3. Category III (electrical equipment for explosive dust environment) has been added to the equipment classification.
4. Incorporate "N" electrical equipment (spark-free electrical equipment) into the general requirements, that is, first meet the provisions of the general requirements.
5. The moistureproof requirements for Class I electrical equipment are added in Appendix C. The test period of high-voltage electrical equipment is 21d at +40℃; ;
Low-voltage electrical equipment, under the environment of +40℃, the test period is 12d. The test method is in accordance with GB/T 2423.4- 1993.
6. Explosion-proof signs have been improved. The original explosion-proof signs are arranged in order of symbol Ex, explosion-proof type, category symbol and temperature group (only applicable to Class II electrical equipment). Now the equipment protection level is added after the original explosion-proof mark, and there is a small interval between the marks.
For example, the explosion-proof mark of mine motor used to be Exd, but now it is Ex dⅰMb.
The explosion-proof mark of the factory motor used to be EXD Ⅱ T4, but now it is Ex dⅱT4 Gb.
7. In the chapter on temperature, "external heat source or cold source" is added as a factor affecting the environment.
8. The requirement of "zirconium" content has been added to the light metal shell material.
9. Requirements for the preparation and detailed contents of the product instruction manual have been added.
10. The chapter "manufacturer's responsibility" has been added to the new standard. In the old standard, the inspection procedure for obtaining explosion-proof certificate was the single requirement in Appendix A "Inspection Procedure", while in the new standard, the inspection procedure for obtaining explosion-proof certificate is required in the manufacturer's responsibility.
Second, the main differences between the old and new GB3836.2 standards
1, IEC 60079- 1: 2007 is adopted for the new standard revision, and IEC 60079- 1: 1990 is adopted for the old standard equivalent.
2. The standard name is changed from flameproof type "D" to equipment protected by flameproof shell "D".
3. Threadless flameproof joint faces increase the requirements for tapered joint faces and joint faces with arc faces.
4. In the chapter "Transparent parts", the requirements for materials and installation methods of transparent parts were deleted.
5. The requirements for the yield strength of fasteners and seals have increased.
6. The chapter "Fasteners" was changed to "Fasteners, related holes and blocking parts". In this chapter, the yield strength requirements of fasteners and the requirements of stoppers are added.
7. The lead-in device of flameproof enclosure is subdivided into cable lead-in device, conduit sealing device, plug socket, cable connector and insulating sleeve, and the specific requirements for each lead-in device are added.
8. In terms of the mechanical strength of the shell, cast iron is added as the shell material, and the material grade should not be lower than the requirement of 150.
9. The condition of determining the highest surface temperature was added in the inspection and test.
10, type test "shell strength test", adding the measurement method when the ambient temperature is lower than -20℃.
1 1. The original appendix A "Non-metallic parts of explosion-proof enclosure" is included in the text.
Third, the main differences between the old and new GB3836.3 standards
1, the new standard is equivalent to IEC 60079-7: 2006, and the old standard is equivalent to IEC 60079-7: 1990.
2. The standard name is changed from the increased safety type "E" to the equipment protected by the increased safety type "E".
3. Modify the electrical connection, and change "connector" and "internal wiring" into "electrical connection". Electrical connections are divided into universal, field wiring connectors and factory connectors.
4. The voltage levels, corresponding values and related notes in the table of creepage distance and electrical clearance are modified.
5. In the chapter of protection grade of enclosure, the requirement that enclosure should be equipped with drainage holes or ventilation holes was added.
6. Requirements for evaluating the rotor structure that may generate air gap sparks have been added. If the sum of the factors after evaluation is greater than 6, additional tests should be carried out on the rotor or special protection (ventilation and purging device) should be provided for the motor.
7. The requirements for installing anti-condensation heaters and special protective measures (ventilation and purging devices) on the motor stator with rated voltage exceeding 1kV have been added.
8. The limit temperature requirement of stator winding terminals is increased.
9. Relevant requirements for bearing seal and shaft seal have been added.
10, adding additional test requirements for high-voltage motors. The additional test is harsh, and the stator winding is subjected to withstand voltage and pulse test in explosive gas mixture; The rotor is subjected to aging test first, and then 10 full-pressure no-load start-up or 10 rotor locking test is carried out in explosive gas mixture.
9. Add letters A, B and C after category symbol II of explosion-proof sign of high-voltage motor.
For example, in the environment where ethylene may appear occasionally and in a short time, the explosion-proof mark of the safety-increased motor is EXE Ⅱ T3, and the current explosion-proof mark is EXE Ⅱ BT3 according to the new standard.