【Industry Standards】Single-phase three-pin plug sockets and connectors for stage lighting – types, basic parameters, and dimensions

5.3 Electrical accessories shall be easy to insert and remove, and the force required to remove them shall comply with the specifications in Table 2.

5.4 Insulation resistance and dielectric strength of electrical accessories

5.4.1 Insulation resistance

After applying a DC voltage of 500 V for 1 minute, the insulation resistance should be greater than 5 MΩ. The measurement is taken between all the poles connected together and the main body of the device; measurements are also taken alternately between each pole and the other poles.

5.4.2 Dielectric strength

A voltage test is conducted using an AC voltage of 2000 V at a frequency of 50 Hz (2500 V for metal enclosures with insulating padding) for 1 minute. No flickering or breakdown should occur during this test. The measurement points are the connection between all the poles and the main body, as well as between each pole and the other poles in turn.

5.5 Temperature rise

Cables with a length of at least 2 meters and a cross-sectional area specified in Table 3 are connected to the electrical accessory, and the device is tested by applying a current equal to 125% of its rated current. In this case, the temperature rise in the conductive parts and the grounding parts should not exceed 40°C.

5.6 The strain plates on plugs and connectors must be made of insulating material; when connecting the cables specified in Table 3 and a pulling force is applied, the displacement of the cables should not exceed 2 mm.

5.7 The grounding terminals and the wire connections of the conductive terminals in electrical accessories must not present any risk of accidental contact.

5.8 The plugs of electrical accessories should not come loose from their corresponding sockets when subjected to a force 1.2 times greater than the maximum pulling force specified in Table 2; moreover, such plugs should provide protection against electric shock.

5.9 Electrical accessories must have sufficient breaking capacity.

For plugs and sockets or connectors, 50 insertion and removal cycles should be carried out at currents up to 32A (including 32A), without any continuous arcing occurring during these tests. After the tests, the samples should not suffer any damage that would prevent them from being used further.

5.10 Electrical accessories must be able to withstand the mechanical, electrical, and thermal stresses encountered during normal use, without experiencing excessive wear or other harmful effects. The number of insertion and removal cycles is as follows: 5000 cycles for currents up to 16A (including 16A), and 2000 cycles for currents up to 32A. These cycles should include one insertion/removal cycle with current applied and one without current, in an alternating manner.

5.11 Mechanical strength of electrical accessories

5.11.1 For the impact test, the weakest part of the exposed areas of the electrical accessories shall be struck 3 times using the spring impact device specified in Table 4; after the test, the sample must meet the following requirements.

a. Live components must not become accessible;

b. The casing must not have any visible cracks;

c. The leakage distance must not be reduced.

5.11.2 After 8 drop tests, the components of the cable connector must not come loose or separate.

5.12 Screws and nuts that serve for electrical or mechanical connections in electrical accessories must be able to withstand the mechanical stresses encountered during normal use.

5.13 The creepage distance, clearance distance, and insulation penetration distance in electrical accessories shall not be less than the values specified in Table 5.

5.14 Electrical accessories must be able to withstand the humid and hot conditions that may arise during normal use.

5.15 Electrical accessories should have sufficient heat resistance.

5.16 The type, basic parameters, and dimensions of electrical accessories rated at 16A and 32A shall comply with the provisions in Figures 2 to 4 and Table 6.

5.17 Cables must be terminated using compression connectors. When electrical accessories are in normal use, the compression screws must not come loose and separate from the conductive plates.

5.18 Outdoor electrical accessories should have a protection rating of at least IP44.

6 Testing Methods

Unless otherwise specified, the samples shall be tested at an ambient temperature of (20 ± 5)°C (with factory testing carried out between 5°C and 35°C), at the rated frequency, under the conditions as they are at the time of delivery and under normal operating conditions.

The accuracy of the electrical measuring instruments used for testing must be at least 0.5 grade (except for megohmmeters and frequency meters); however, 1.0 grade instruments may be used for factory testing. The accuracy of length measurement instruments must be at least 0.02 mm.

All values are given in millimeters.
 

                             图2 输入插头

                             图3 输出插头
 

6.1 Visual inspection of items 5.1.1, 5.1.3, 5.1.4, and 5.2 shall be carried out.  

6.2 Rust prevention (5.1.2)  

Rust prevention tests shall be conducted in accordance with the requirements of Chapter 31 of GB 4706.1.  

6.3 Pulling force (5.3)  

Maximum pulling force: The sample is fixed as shown in Figure 5; a standard plug is inserted into the sample. The combined weight of the main load, the additional load (whose force is 1/10 of that of the main load), as well as the weight of the standard plug and fixtures, equals the maximum pulling force specified in Table 2.

                               单位为毫米                       图5 拔出力试验装置

        The main weight should be suspended in such a way that the test plug is not subjected to any shocks, allowing an additional weight to fall on the main weight from a height of 5 cm. The plug must not remain attached to the weight.

The minimum pulling force for a unipolar connection is determined by using a hardened steel gauge (pin) with a surface roughness of Ra 2 μm. Its basic dimensions are 0.2 mm smaller than the specified pin diameter, with a tolerance of 0.01 mm. This gauge is inserted into each corresponding socket to measure the force required to pull it out.

The sum of the force applied and the weight of the gauge must be greater than the minimum pulling force specified in Table 2. This test is carried out after the maximum pulling force test.

6.4 Insulation Resistance and Dielectric Strength (5.4)

6.4.1 Insulation Resistance (5.4.1)

Measurements are taken using a 500V megohmmeter.

6.4.2 Dielectric Strength (5.4.2)

The voltage applied at the start of the test should not exceed half of the specified value; it should then be increased rapidly to the specified value.

6.5 Temperature Rise (5.5)

After energization, the device is left under load for 1 hour at currents up to 32 A. Temperature rise is measured using melting particles, color-changing indicators, or thermocouples.

6.6 Cable Compression Force (5.6)

Cables with maximum (minimum) diameters as specified in Table 3 are used. These cables are connected to the electrical components, and the cables are compressed using clamps. The wire cores are not connected to any terminals. The sample is then fixed to the lever shown in Figure 6, and weights specified in Table 7 are hung from it. The sample is rotated at a speed of 1 rev/s. When the eccentricity is at its smallest value, the weight falls onto the support surface; when the eccentricity is at its largest value, the weight acts on the electrical components. After 100 rotations, the displacement of the marks on the sample is measured.

6.7 Hazards associated with accidental contact (5.7)

Use soft wires that are suitable for electrical accessories to connect to the terminals of the conductive electrodes or wiring terminals, and secure them properly. However, one of the wire cores, with a length of 8 mm, should be left hanging outside the terminal; when this core is moved in various directions, it must not come into contact with any other metal parts.

6.8 Stability of the plug connection and protection against electric shock (5.8)

Fix the test specimen on a support so that the plug points vertically downward. Connect a rope to the plug and hang a weight equal to 1.2 times the pulling force on it; after 1 minute, the plug should not move relative to the insulator.

A standard testing probe is used to conduct tests for protection against electric shock.

The unit of measurement is millimeters.

                                     图6

6.9 Breaking capacity (5.9)  
This test is carried out on specialized equipment using the circuit shown in Figure 7. The sample is fixed in a fixture, and it is inserted and withdrawn at a frequency of 7.5 times per minute (one insertion and one withdrawal count as one cycle). The separation speed is 8.0 cm/s, and the power factor of the alternating current is 0.6 ± 0.05. The number of tests per pole is half of the total number of tests.

6.10 Normal operation (5.10)  
The same equipment and methods as those specified in 6.9 are used, with insertions and withdrawals taken place at a frequency of 7.5 times per minute. After 500 cycles, the plugs of the electrical components should be wiped clean with a dry cloth. After the testing, the device must still be able to withstand the dielectric strength test specified in 6.4.2, although the test voltage is reduced by 500 V.

6.11 Mechanical strength (5.11)  
6.11.1 Impact tests are conducted using a spring impact device that meets the requirements specified in Table 4.  
6.11.2 Drop tests are carried out according to the method shown in Figure 8: one end of the cable is fixed to the wall, the sample is held in hand with the cable in a horizontal position, and then the cable is dropped onto concrete. This process is repeated 8 times, with the cable being rotated 45° around its axis after each drop.  
The units used are millimeters.

                                      图7

6.12 Mechanical Stress (5.12)

     After tightening and loosening 5 times using a screwdriver at the torque values specified in Table 8, the screws and nuts should not suffer any damage that would prevent further use.

6.13 Tracking distance, electrical clearance, and breakdown insulation distance (5.13)  
The compliance with the specified requirements is determined by using the measurement methods outlined in Appendix E of GB 4706.1.  

6.14 Moisture resistance tests are carried out in accordance with the requirements of GB 2423.3; the sample is placed in a humid chamber for 48 hours.  

6.15 Heat resistance (5.15)  
6.15.1 The sample is placed in an oven at a temperature of (100±5)°C for 1 hour, after which it is checked to determine whether any damage that could affect its functionality has occurred.  
The unit of measurement is millimeters.

                                      图8

6.15.2 Using the equipment shown in Figure 9, the surface of the parts made of insulating material should be placed in a horizontal position, and a steel ball with a diameter of 5 mm should be applied to this surface with a force of 20 N. The test is carried out in an oven; the temperature for the parts that are under electrical stress is (125±5)°C, while for the other parts it is (80±5)°C. After 1 hour, the steel ball is removed, and the diameter of the impression left on the surface should not exceed 2 mm.

6.16 Compatibility (5.16)

The type, basic parameters, and dimensions of electrical accessories of 16A and 32A ratings are measured using a vernier caliper with a resolution of 0.02 mm, and these accessories can be used interchangeably with each other.

6.17 Reliability of connections (5.17)

The screws are loosened using a screwdriver, and then an visual inspection is performed.

7 Inspection rules

7.1.1 The items included in the factory inspection are those specified in sections 4.1, 5.2.2, 5.2.3, 5.4, and 8.1 of this standard.

7.1.2 The methods for factory inspection are determined in accordance with GB 2828, as shown in Table 9. For products classified as category A defects, each individual product must be inspected; if a fatal defect is found in a batch of products, then the entire batch is considered defective.

The unit of measurement is millimeters.

                             图9 球压装置       

The distinctions between Class A failures, Class B failures, and Class C failures are shown in Table 10.

A sample is considered qualified only when it meets the required quality standards for all of Class A, Class B, and Class C failures.

For the 19 items listed in Table 10, if even one of them fails to meet the specified requirements, then that item is deemed not to meet the standard.

7.1.3 In batch sampling inspections, the sampling rules outlined in GB 2828 are applied. When the quality of a batch is stable and reliable, it is possible to switch from normal inspection to simplified inspection; otherwise, the inspection must be intensified.

7.2 Products must undergo type testing in any of the following situations; products that have not undergone type testing shall not be put into production.

a. When a new product or an existing product is being developed for production at a different factory;

b. After regular production begins, if there are significant changes in the structure, materials, or manufacturing process that could affect the product’s performance;

c. As part of regular sampling inspections of products manufactured continuously;

d. When production resumes after a long period of interruption;

e. When there are significant differences between the results of factory inspections and those of previous type tests;

f. When national quality supervision agencies request that type testing be carried out.

                                      表10

7.2.1 For type inspection, a group of (3) products shall be randomly selected from the batch for testing.  
7.2.2 If more than 2 products out of those tested fail to meet the requirements in a particular test item, then the entire batch is considered unacceptable; if only 1 product fails, another group of (3) samples must be taken for retesting of that item. If it still fails, the batch is deemed unacceptable, and the cause must be identified and resolved until the tests pass. The applicant for testing may submit two groups of products for testing at the same time.  

8 Marking, Packaging, Transportation, and Storage  

8.1 Marking  
8.1.1 Electrical accessories must have the following clear, legible, and durable markings:  
 a. Manufacturer’s name or trademark;  
 b. Rated voltage and rated current;  
 c. Grounding symbol;  
 d. Neutral line symbol N.  
8.1.2 Packaging boxes must carry the following markings:  
 a. Product name and specifications;  
 b. Manufacturer’s name and trademark;  
 c. Quantity and weight;  
 d. Standard code.  

8.2 Packaging  
8.2.1 Electrical accessories should be placed in paper or plastic boxes, with insulation provided using corrugated paper or other materials.  
8.2.2 These paper or plastic boxes should then be placed inside dry wooden crates, hard cardboard boxes, or plastic containers, with measures in place to prevent moisture or vibrations.  
8.2.3 The weight of each box (large container) should not exceed 25 kg.  
8.2.4 The packaging box must contain a certificate of conformity for the product.  

8.3 Transportation and Storage  
8.3.1 During transportation, protection from rain and severe vibrations is necessary.  
8.3.2 Electrical accessories should be stored in well-ventilated and dry areas.