NB/T 10304-2019Bimetal thermal protectors for ballasts used in tubular fluorescent lamps (English PDF)

3.1 Ballast

A device composed of inductance, capacitance or resistance, single or combined, is connected between the power supply and one or more discharge lamps, which is mainly restricted The current acts and produces instantaneous high voltage.

3.2 Thermal ballast protector

Installed in or integrated with the ballast of tubular fluorescent lamps, designed to prevent the ballast from overheating under any conditions. Position type automatic controller.

Note: The thermal protector carries the current of the ballast and is sensitive to the temperature and current of the ballast.

3.3 Rated current

The current specified by the manufacturer for the thermal protector.

3.4 Open temperature

The thermal protector does not carry any current, or only the signal current passes through, and the cut-off temperature value measured under a certain heating rate condition.

3.5 Reset temperature

The closing temperature value of the thermal protector measured under a certain cooling rate.

3.6 Internal resistance

The resistance generated by mechanical contact and current-carrying parts on the current-carrying circuit in the thermal protector.

3.7 Current-temperature characteristics

In the set ambient temperature, the thermal protector does not disconnect the maximum continuous current that the circuit can carry.

5.1 General requirements

5.1.1 Appearance and size requirements. the installation size and product mark are clear, and the content meets the requirements of the relevant documents of the manufacturer.

5.1.2 The metal parts shall not have cracks and peeling off of the coating, and the insulating materials shall not have bubbles, cracks, no obvious marks and damages, etc. Elephant.

5.1.3 Where there are regulations on the installation method or the performance of the thermal protector is affected by the installation conditions, the installation conditions or Agreement with the user to determine the installation conditions.

5.1.4 When there is a requirement for leak prevention during the dipping process, it should be able to ensure its good leakproof ability, and if necessary, the verification method should be agreed with the user and compared Such as dipping paint together with the ballast.

5.1.5 The structure of the lead-out components (wires, terminals, welding pieces, etc.) should ensure good electrical contact and current-carrying capacity, and be able to withstand corresponding The requirements for mechanical stress are determined by agreement with the user.

5.1.6 The insulating material of the thermal protector shall be able to withstand the following requirements for heat resistance, flame resistance and tracking resistance.

a) Heat resistance. the ball pressure test of the maximum working environment temperature of the thermal protector Tmax+40°C;

Note: Ceramic materials are not subject to this test.

b) Flame resistance. test temperature test at the top of the glow wire at 650°C±10°C, duration 30s±1s;

c) Tracking resistance. PTI is not less than 175 V.

5.2 Performance requirements

5.2.1 Operating temperature

The operating temperature of the thermal protector is between 60°C and 150°C every 5°C, and the allowable deviation of its operating temperature is ±5°C.

5.2.2 Reset temperature

The on-off temperature difference of the thermal protector should be within the range declared by the manufacturer, preferably (5-25)K, (10-40)K.

Note: Other operating temperature, reset temperature and deviation can be set according to user needs.

5.2.3 Current-temperature characteristics

The manufacturer of the thermal protector should reflect the current-temperature characteristics of the thermal protector in the form of a chart or curve. The user agreement is determined.

5.2.4 Internal resistance

In general, the internal resistance between the two lead parts of the thermal protector product should not be greater than 50 mohm.

Note: Other internal resistance values can be set according to product structure characteristics and customers.

5.2.5 Insulation resistance

The insulation resistance of the thermal protector should meet the following requirements.

a) The insulation resistance between the two lead parts of the thermal protector should not be less than 2 Mohm when the contacts are thermally disconnected;

b) The insulation resistance between the lead-out parts of the thermal protector and the surface of the insulation layer of the enclosure should not be less than 5 Mohm.

5.2.6 Electric strength

The insulation or disconnection of the thermal protector should be able to withstand the basic sine wave with a frequency of 50 Hz or 60 Hz, according to the test voltages in Table 1 and Table 2 (with Effective value) There is no flashover and breakdown in 1min, and the leakage current trip value setting during the test shall not exceed 10 mA.

5.2.7 Overload

Under the conditions of rated voltage and power factor of 0.4 to 0.5, the thermal protector is switched on and off for 1,000 cycles with 4 times the rated current. After the test, The operating temperature change does not exceed ±5K of the initial value.

5.2.8 Durability

Under the conditions of rated voltage and power factor of 0.4~0.5, the thermal protector is switched on and off for 10 000 cycles with 2 times the rated current. After the test Should meet.

a) The operating temperature change does not exceed ±5K of the initial value;

b) The electrical strength meets the requirements of 5.2.6;

c) The contacts must not malfunction;

d) The contact does not weld.

5.2.9 Limited short circuit performance

The thermal protector shall withstand the limited short-circuit performance test with an expected current of 200 A without causing a fire hazard, and allow the thermal protector contact to melt Welded or broken.

5.2.10 High temperature resistance

The thermal protector should be able to withstand the high temperature test requirements of 150°C for 96 hours, and the change in the operating temperature of the thermal protector shall not exceed the initial ±5K of the initial value.

5.2.11 Resistance to temperature changes

The thermal protector is cycled for 10 cycles at the severe level according to the temperature change requirement of 60°C for 4 hours and low temperature of -40°C for 2 hours, after the test The change in operating temperature does not exceed ±5K of the initial value.

5.2.12 Vibration resistance

The thermal protector should be able to withstand a constant frequency test with a vibration frequency of 50 Hz, an amplitude of 0.35 mm, and a duration of 30 minutes. After the test, its operating temperature changes Does not exceed the initial value ±5K.

5.2.13 Impact resistance

The thermal protector should be able to withstand the peak acceleration of 50 gn ± 7.5 gn, and the pulse duration of the back peak sawtooth half sine wave with a pulse duration of 11 ms ± 1 ms.

Speed impact test, after the test, the change in operating temperature does not exceed the initial value ± 5K.

5.2.14 Humidity and heat resistance

The thermal protector should be able to withstand the severity level according to the temperature of 25°C±2°C in GB/T 2423.3-2016, and the relative humidity of 91%~95%.

During the 7-d damp and heat resistance test, after the test, in the contact thermally disconnected state, the insulation resistance between the lead part and the surface of the housing insulation layer should not be less than 2 M ohm, and can withstand 5.2.6 electric strength performance test, the test voltage is reduced to 80% of the original.

6.1 Test conditions

Unless otherwise specified, the test should be carried out under the following conditions.

a) The ambient temperature is 10°C~30°C, and the surrounding air temperature should not exceed 10°C during the test;

b) The accuracy of test instruments and meters. the factory inspection is not less than 1.0, and the type test is not less than 0.5;

c) Humidity requirements. relative humidity 45%~75%;

d) Accuracy of temperature measuring instrument. not lower than 0.5°C in factory inspection and not lower than 0.2°C in type test.

6.2 General inspection

6.2.1 Appearance and size inspection

Use general or special measuring tools to check the size and visually check whether the appearance meets the requirements of 5.1.1 and 5.1.2.

6.2.2 Heat resistance, flame resistance and tracking resistance test of insulating parts

The heat resistance, flame resistance and tracking resistance test of insulating parts shall be tested in accordance with 5.1.6 and Chapter 21 of GB/T 14536.1-2008.

Note: When necessary, use plastic samples to conduct heat resistance, flame resistance and tracking resistance tests of insulating parts.

6.3 Performance test

6.3.1 Action temperature test

Place the thermal protector in a strong convection dry box for testing.

The measurement method adopts thermocouple or thermometer. The thermocouple or thermometer should be placed on the thermal protector sample or as close as possible to the thermal protector.

Increase the air temperature in the test, and the temperature change rate when the air temperature is about 10K lower than the lower limit temperature of the operating temperature does not exceed 1 K/min Until the thermal protector operates, check whether the operating temperature meets the requirements of 5.2.1.

Use indicator lights or other methods to indicate the on-off status, and allow the current through the thermal protector to not exceed 0.01 A.

6.3.2 Reset temperature test

For the automatic reset thermal protector, use the method specified in 6.3.1 to carry out the reset temperature test, reduce the air temperature, and When the upper limit temperature of the bit temperature is 10K, the temperature change rate does not exceed 1K/min. When the thermal protector is reset, check whether the reset temperature meets the regulations of 5.2.2. set.

6.3.3 Current-temperature characteristic test

Place the thermal protector in a relatively still air with a temperature fluctuation of ±2°C for testing.

In the test, keep the ambient temperature at any temperature point lower than the cut-off temperature, and pass the non-operation of the thermal protector at this temperature Current for 1h, check whether the result meets the requirements of 5.2.3.

6.3.4 Internal resistance test

Use a resistance measuring instrument to measure the resistance between the two lead parts of the thermal protector, and check whether the result meets the requirements of 5.2.4.

6.3.5 Insulation resistance test

Use a 500 V insulation resistance tester to test the insulation resistance of the thermal protector according to the following method, and check whether the result meets the requirements of 5.2.5.

In the insulation resistance performance test between the contacts, the thermal protector should be placed in an air medium that is approximately 10K higher than the upper limit temperature of the test product's disconnection temperature In the case of contact disconnection.

The insulation resistance performance test between the lead-out part of the thermal protector and the insulating surface layer of the enclosure is carried out at room temperature.

6.3.6 Electric strength test

Electric strength performance test, the test power capacity is not less than 0.5 kVA, the frequency is 50 Hz or 60 Hz basic sine wave, its maximum leakage The leakage current trip value is set to 10 mA.

Start from half of the test voltage at the position described in 5.2.6, gradually increase to the specified value, and continue for 1 min to observe whether there is breakdown or flashover. Elephant.

Note 1. The electrical strength performance test between the two contacts is to place the thermal protector in an air medium that is approximately 10 K higher than the upper limit temperature of the disconnect temperature of the test product. The head is disconnected.

Note 2. The electrical strength performance test between the current-carrying part and the outer surface of the insulating part is carried out at room temperature.

Note 3. The factory inspection allows to increase the test voltage by 20% and shorten the pressure time to 1 s.

6.3.7 Overload test

Connect the thermal protector product to a circuit with a rated voltage and a power factor of 0.4 to 0.5, pass 4 times the rated current, and the allowable current The difference is ±5%, the operating frequency (on-off-on time) is 5 cycles/min to 7 cycles/min, and the cycle rate depends on the surrounding medium.

Temperature, after this cycle for 1,000 cycles, check whether the result meets the requirements of 5.2.7.

6.3.8 Durability test

Connect the thermal protector product to a circuit with a rated voltage and a power factor of 0.4 to 0.5, pass 2 times the rated current, and the current tolerance In a circuit of ±5%, the operating frequency (on-off-on time) is 5 cycles/min to 7 cycles/min, and the cycle rate depends on the control surroundings If the temperature of the medium is circulated for 10 000 cycles, check whether the result meets the requirements of 5.2.8.

6.3.9 Limited short-circuit performance test

Connect the thermal protector in series with the 20 A fast fuse (the fuse must not be disconnected within 12 s when the 40 A current is applied), and wrap the heat with absorbent cotton wool After the shell of the protector is connected to a circuit with an expected current of 200 A and a power factor of 0.9 to 1.0, the thermal protector is allowed to repeat during the test Action, the test should be carried out until the thermal protector permanently disconnects the circuit or the fuse is blown, and check whether the result meets the requirements of 5.2.9.

6.3.10 High temperature resistance performance test

Put the thermal protector into the 150°C±3°C test box and keep it for 96 hours, then take it out and keep it at room temperature for 1 hour and then perform the action temperature test. Check whether the result meets the requirements of 5.2.10.

6.3.11 Resistance to temperature change performance test

Place the thermal protector in an environment of -40°C±3°C, keep it for 2 hours, take it out and keep it in the air for 30 minutes, then put it at 60°C±3°C In the drying box, keep it for 4 hours and then take it out and keep it at ambient temperature for 30 minutes. After 10 cycles of this cycle, perform the action temperature test to check the result. Whether the results meet the requirements of 5.2.11.

6.3.12 Vibration resistance test

Fix the thermal protector on the test bench, in each direction in X, Y, Z 3 mutually perpendicular directions according to the requirements of 5.2.12 Carry out a 10 min vibration test to check whether the result meets the requirements of 5.2.12.

6.3.13 Impact resistance test

Fix the thermal protector on the test bench, in each direction in X, Y, Z directions perpendicular to each other according to 5.2.13 Apply 3 consecutive shocks for a total of 18 shock tests to check whether the results meet the requirements of 5.2.13.

6.3.14 Humidity and heat resistance test

This test adopts the Cab test method. For the requirements of the test box, see GB/T 2423.3-2016 Part 2 Test Method, according to 5.2.14 Perform the test according to the specified severity level and the 7th requirement of GB/T 2423.3-2006, and check whether the result meets the requirements of 5.2.14.

Regarding the test of the sample, the insulation resistance and electric strength test of the lead-out part and the insulating outer layer should be carried out immediately after the end of the test.

Under normal atmospheric pressure conditions, and avoid condensation on the sample.

Within 1 h~2 h, put the test sample in the air medium 10K higher than the upper limit temperature of the disconnection temperature, and when the contact is disconnected, use 500 The V megohmmeter measures the insulation resistance between the lead parts, and then conducts the electrical strength test between the lead parts.

7.1 Inspection classification

Inspection is divided into two types. type inspection and factory inspection.

7.2 Type inspection

7.2.1 Applicability of type inspection

When one of the following conditions exists for the thermal protector, type inspection should generally be carried out.

a) When the new product is finalized or the old product is transferred to the factory;

b) After formal production, if there are major changes in structure, materials, and processes, which may affect product performance;

c) When production resumes one year after the product has been discontinued;

d) During normal production, once a year;

e) When the product standard is updated and the content changes significantly;

f) When the national quality supervision agency requests for type inspection.

7.2.2 Type inspection rules

The thermal protector used for type inspection should be a formal test product with complete main manufacturing process and equipment. Each test item should be no less than 3 tests.

In this way, the thermal protector is considered qualified if all the test items pass, otherwise the reasons should be analyzed and technical measures should be taken, including Improve technology, craftsmanship, tooling, etc., and repeat until the type inspection is qualified.

7.2.3 Type inspection items

Type inspection items are divided into 3 groups with 3 samples in each group. See Table 3 for details.

7.3 Factory inspection

7.3.1 Factory inspection classification

The factory inspection is divided into full inspection and sampling inspection.

7.3.2 Total inspection

7.3.2.1 Total inspection rules

Full inspection is the process of thermal protector production, each product should be inspected, and the full inspection can be under the same conditions as the type inspection Test methods or rapid test methods. Unqualified products must be reworked or repaired one by one until they are fully qualified. If they cannot be repaired, they should To scrap.

7.3.2.2 All inspection items

All inspection items are.

a) Operating temperature;

b) Reset temperature;

c) Internal resistance; d) Electric strength.

7.3.3 Sampling inspection

7.3.3.1 Sampling inspection rules

Sampling inspection is the final inspection before the thermal protector leaves the factory. The sampling inspection is carried out in accordance with the provisions of GB/T 2828.1-2012.

For batch products that are judged to be unqualified, all products in the batch (or within the period) should be reworked or repaired, and only allowed to leave the factory after passing the inspection.

The sampling inspection at the factory adopts the special inspection level "S-4" in Table 1 of GB/T 2828.1-2012 and the normal inspection in Table 2-A. Check the sampling plan once.

The qualified quality level (AQL value) of sampling inspection is shown in Table 4.

7.3.3.2 Sampling inspection items General

sampling inspection items are shown in Table 4.

8.1 Logo

The heat protector mark should be clear, durable and easy to identify. The content of the product mark should include.

a) The name of the manufacturer or registered trademark;

b) Product model or serial number or unique model identification mark;

c) Product specification identification.

8.2 Packaging

8.2.1 The thermal protector should be packaged when leaving the factory to prevent damage during transportation. There should be a product certificate in the packaging box. Documents such as clear books.

8.2.2 The packaging signs should be clear and tidy, and ensure that they are not obscured after transportation or storage. Package mark content.

a) The name or trademark and address of the manufacturer;

b) Product name, model, specification;

c) The number of products;

d) Overall dimensions of the packing box;

e) weight;

f) Date of production;

g) There are words such as "be afraid of wet", "upward", "handle with care", "stacking limit", etc. on the packing box according to GB/T 191-2008 Sample or mark.

8.3 Transportation

The packaging should be adapted to the transportation of various transportation vehicles without damage. The thermal protector shall not be attacked by rain or snow during transportation.

8.4 Storage

The thermal protector should be stored in a well-ventilated, non-corrosive medium, and the relative humidity is less than 90% (20°C±5°C), and the ambient temperature is not In warehouses above 40°C and not below -5°C, the storage period should not exceed three years.