This standard specifies the product classification, technical requirements, inspection force methods, inspection rules, markings and user manuals, packaging, storage, transportation, and other requirements for underfrequency relays and devices. This standard applies to underfrequency relays and devices (hereinafter referred to as products), which are used for power system grid stability control. When the system frequency drops, they automatically cut off some loads or disconnect the power grid to ensure safe and reliable operation of the power system. This standard only applies to new products. 2. The provisions contained in the following standards constitute the provisions of this standard by reference in this standard. At the time of publication of the standard, all versions shown are valid. All standards will be revised, and parties using this standard should explore the possibility of using the latest versions of the following standards. GB/T 1.3-1997 Guidelines for Standardization Work Unit 1: Rules for Drafting and Expressing Standards Part 3: Regulations for Writing Product Standards GB/T 2900.17-1994 Electrotechnical Terminology Electrical Relays (evq IEC 60050 (IEV 446): 1977) GB/T 7261-1987 Basic Test Methods for Relays and Relay Protection Devices GB/T 14598.9-1995 Electrical Relays Part 22: Electrical Interference Tests for Measuring Relays and Protection Devices Part 3: Radiated Electromagnetic Field Interference Tests (idt IEC 6025522-3:1989) GB/T 14598.10-1996 Electrical Relays - Part 22: Electrical Interference Testing for Measuring Relays and Protection Devices - Part 4: Fast Transient Interference Testing: (idt IEC 60255-22:4: 1992) GB/T 14598.13-1998 Electrical Interference Testing for Measuring Relays and Protection Devices - Part 1: 1 MHz Pulse Group Interference Test (eqv IEC 60255-22-1:1998) GB/T 14598.14-1998 Electrical Disturbance Testing for Measuring Relays and Protective Devices - Part 2: Electrostatic Discharge Disturbance Testing (idt IEC 6025522-2:1996) JB/T 7828-1995 Technical Conditions for Packaging, Storage and Transport of Relays and Their Devices
Function of testing report:
1. Project bidding: Issue authoritative third-party CMA/CNAS qualification report
2. Online e-commerce platform entry: Quality inspection report recognized by major e-commerce platforms 3. Used as a sales report: issuing legally effective testing reports to make consumers more confident 4. Papers and research: Provide professional personalized testing needs 5. Judicial services: providing scientific, fair, and accurate testing data 6. Industrial problem diagnosis: Verify the troubleshooting and correction of industrial production problemsBaijian and testing process:
1. Telephone communication and confirmation of requirements
2. Recommend solutions and confirm quotations 3. Mail samples and arrange testing 4. Progress tracking and result feedback 5. Provide reports and after-sales service 6. If urgent or priority processing is requiredTesting and testing characteristics:
1. The testing industry is fully covered, meeting different testing needs
2. Fully cover the laboratory and allocate localized testing nearby3. Engineers provide one-on-one services to make testing more accurate
4. Free initial testing, with no testing fees charged
5. Self service order delivery for free on-site sampling
6. Short cycle, low cost, and attentive service 7. Possess authoritative qualifications such as CMA, CNAS, CAL, etc 8. The testing report is authoritative and effective, and is generally used in China