Test Item of UL Product

1. Cover Strength Test

Test method: Press the product at the position of air inlet and the air outlet vertically with a test finger whose diameter is 6.4mm*127mm. The force of the pressure should be 5 pounds and should last for one minute.

Demand:

During the test, the uninsulated electrified parts should not be touched by the test finger; after the test, the distance between the uninsulated electrified parts should not reduce. (No less than 1.6mm)

 

2. Input Test

A. Test the power, the rotational speed, wind velocity, motor voltage, and motor electric current, observe whether the heat wire turns red (with no accessory, adjustable resistance or diffuser)

B. Blow the board freely at the distance of 1’’. Measure the temperature of the trip and observe whether it trips or the product is shut down within 15 minutes

 

3.Normal Temperature Test

Test method:

Run the sample at the rated power for 30 minutes. The distance between the air outlet and the thermocouple board should be 1’’. Measure the temperature of each point of the thermocouple board.

Demand:

The highest average temperature rise of the five points at the galvanic board is no more than 100 degrees.

 

4. Motor Deceleration Test No.1

Test Condition and Method:

Separate the motor of the sample and the coil holder. Connect the motor to DC supply. Connect the coil holder to the other motor with the electric cord to imitate a whole sample. Input to the motor the DC voltage which is required at the rated voltage. Input to the sample 110% of the rated power. When it reaches heat balance, the voltage of the DC motor should be reduced at the rate of 1V per minute. After the tripping of the switch, increase the motor’s voltage at the rate of 1V per minute till the tripping stops. When the hot balance is reached, record the temperature of the 52 points of the 1’’ board corresponding to the air outlet. The average temperatures of the highest 5 points are no more than 100?

Result to be recorded:

Normal voltage of motor, voltage when the tripping operation is on, voltage when the tripping operation stops, temperature record of all the points, the temperature of the highest 5 points, the average temperature of the highest 5 points, the average temperature rise of the highest 5 points.

 

5. Motor Deceleration Test No.2

Test condition and method:

Separate the motor of the sample and the coil holder. Connect the motor to DC supply. Connect the coil holder to the other motor with the electric cord to imitate a whole sample. Input to the motor the DC voltage which is required at the rated voltage. Input to the sample 110% of the rated power. When it reaches heat balance, the voltage of the DC motor should be reduced at the rate of 1V per minute. After the thermofuse is broken, short it. Under the circumstances which other conditions are the same, increase the motor’s voltage by 1V. When the hot balance is reached, record the temperature of the 52 points of the 1’’ board corresponding to the air outlet. The average temperatures of the highest 5 points are no more than 100?

Result to be recorded:

Normal voltage of motor, voltage when the thermo fuse is broken, the motor voltage at the last test, the temperature of the highest 5 points, the average temperature of the highest 5 points, the average temperature rise of the highest 5 points.

 

6. Insulation Withstand Voltage Test

Turn on the switch at the highest level. Cover the sample’s surface with metal leaf. Input the voltage of 1,000V between the metal leaf and the plug of the power cord for 1 minute.

Demand:

The leakage current should be no more than 0.5mA.

 

7. Product Coverage Test

Test condition and method:

A. Cover a piece of corkboard with two layers of thin paper. Lay the corkboard horizontal.

B. Connect the uncharged metal of the sample to the ground with a 3A fuse. Lay the sample on the corkboard. Make it work at the rated voltage or power till the hot balance is reached.

C. Cover the sample with two layers thin gauze. Make it work for 7.5 hours or run it till the final result is received.

Demand:

The 3A fuse is in good condition. There are no phenomena such as burning, smoking, charring of the white gauze or distortion of the crust.

 

8. Motor Coverage Test

Test method:

1. Fix two samples. The direction of one sample’s air outlet is parallel to horizon. The direction of the other sample’s air outlet inclines towards the angle of 45° downward.

2. Block the fan blade of the sample with some tools and cover it with two layers of gauze.

3. Switch on the product; make it run at the rated voltage for 7 hours. (Repeat the test with the switch on every single level)

Demand:

There are no phenomena such as burning, smoking, sol of the shell or the possibility that the test finger can touch the charged body. If a short circuit happens, the current at that time should be no more than 15A.

 

9. Temperature-Control Short-Circuit Abnormal Operation Test

Test condition and method:

Separate the motor of the sample and the coil holder. Connect the motor to DC supply. Connect the coil holder to the other motor with the electric cord to imitate a whole sample. Short the trip of the coil holder. Connect the motor to the DC voltage which is needed by running the product at the rated voltage. Input 110% of the rated power. When it reaches heat balance, the voltage of the DC motor should be reduced at the rate of 1V per minute till the fuse is broken.

Demand:

1. The shell should not be punched and cannot be inserted by the test finger.

2. The product should not burn or smoke;

3. Do the high voltage test by covering the sample with tin foil, 1000V, 0.5MA, 1MIN.

 

10. Air Inlet Coverage Test No.1

Test method:

Connect the uncharged exposed metal components to the ground with a fuse of 3A. Adjust the sample to the worst position according to the temperature. The product is laid in different states. Turn on the switch on the high level at 110% of the rated power. After 3 minute’s preheating, cover the air inlet with a piece of single layer gauze every 3 minutes gradually till the tripping switch works. The sample works for 7.5 hours.

Demand:

The fuse of sample and ground is normal. The cover should not melt, smoke or burn.

Result to be recorded:

The time when the fuse is broken; the number of layers of the thicker gauze.

 

11. Air Inlet Coverage Test No.2

Test method:

Connect the uncharged exposed metal components to the ground with a fuse of 3A. Adjust the sample to the worst position according to the temperature. The product is laid in different states. Turn on the switch on the high level at 110% of the rated power. After 3 minutes’ preheating, cover the air inlet with a piece of single layer gauze every 3 minutes gradually till the fuse is broken.

Demand:

3A Fuse is normal. The cover should not melt. The product should not smoke or burn.

Result to be recorded:

Time of fuse movement, number of thickened gauze layers

 

12. Air Outlet Coverage Test No.1

Test condition and method:

Connect the uncharged exposed metal components to the ground with a fuse of 3A. Adjust the sample to the worst position according to the temperature. The product is laid in different states. Turn on the switch on the high level at 110% of the rated power and make it work for 3 minutes. Block the air outlet from the top, the edge, or the bottom. The cover area is increased once every 3 minutes. The position of the cover is about 50%, 75%, 90% and 100% of the air outlet till the tripping switch works. The sample works for 7 hours.

Demand:

3A fuse to earth and fuse of sample is normal and should not burn or smoke. Cover should not melt.

(In the test report, a coverage schema is necessary.)

 

13. Air Outlet Coverage Test No.2

Test condition and method:

Test condition and method: Connect the uncharged exposed metal components to the ground with a fuse of 3A. Adjust the sample to the worst position according to the temperature. The product is laid in different states. Turn on the switch on the high level at 110% of the rated power and make it work for 3 to 5 minutes. Block the air outlet from the top, the edge or the bottom. The cover area is increased once every 3 minutes. The position of the cover is about 50%, 75%, 90% and 100% of the air outlet till the fuse is broken.

Demand:

3A fuse to earth and fuse of sample is normal and should not burn or smoke. Cover should not melt.

(In the report of test, a coverage schema is necessary.)

 

14. Drop Test

Test method:

1. Connect the uncharged exposed metal components to the ground with a fuse of 3A.

2. Switch on the sample and modulate the voltage to make it work at the rated voltage.

3. Make the sample fall on the hard board from 3 different directions at the height of 3 inches.

4. Do the insulation withstand voltage test (1000V, 1MIN, 0.5MA), input test and normal running temperature test.

Demand:

Electrified body should not be touched by the test finger. Insulation should not broke or burn in the three test. The fuse of 3A is in good condition.

 

15. Double Voltage Abnormal Operation Test

Test method:

1. Turn the transformer of the sample to the level of 120V/125V. Turn the switch on with the high level. Connect the uncharged exposed metal components to the ground with a fuse of 3A.

2. Cover the horizontal board with two layers white thin paper. Lay the sample on the board.

3. Connect the sample to the power supply of 240V/250V, 60HZ till achieving the final test result.

Demand:

The product should not burn or smoke. The cover of sample should not melt. 3A fuse is normal.

 

16. Motor Short Circuit Test

Test Method:

Short the both sides of the sample’s motor. Lay the sample on the board covered by two layers of white thin paper. Connect the uncharged exposed metal components to the ground with a fuse of 3A. Switch the product on at the rated power and make it work for 7 hours till achieving the final test result.

Demand:

The thin paper should not burn, melt or smoke. The cover of sample should not melt. 3A fuse is normal.

 

17. Component Open Circuit Test

Test method:

1. Provide an open circuit of voltage reduced heating element to the motor of the sample.

2. Lay the sample on the board covered by two layers white thin paper. Connect the uncharged exposed metal components to the ground with a fuse of 3A.

3. Switch the product on and adjust the voltage to make the product work at the rated power. Make it work for 7 hours till achieving the final test result.

Demand:

The thin paper should not burn or scorch. 3A fuse is normal and should not burn or smoke. The cover of sample should not melt.

 

18. Component Failure Test

1. Test two samples. Turn off one part of the full-wave rectification circuit of one sample. Then turn off one part of the complete rectification circuit of the other sample.

2. Connect the uncharged exposed metal components to the ground with a fuse of 3A.

3. Lay the sample on the cork board covered by two layers white thin paper. Cover the sample with two layers gauze. Switch the product on at the rated power and make it work for 7 hours till achieving the final test result.

Demand:

3A fuse is normal and should not burn or smoke. The cover should not melt. The thin paper should not scorch.

 

19. Power Cord Tensile Test

Test method:

Hang heavy objects of 35 pounds on the power cord of the sample. Pull the power cord in the most adverse direction for 1 minute.

Demand:

The internal boundary part of the power cord should not have tension because of displacement.

 

20. Power Cord Bending Test

Test method:

Fix a heave object of 1/4 pound on power cord in the position of 8 inches away from the handle of the sample. Rotate the center shaft of the handle in the horizontal direction. Move it back and force. Remove it for 540° in each direction and that is a cycle. The rate is 10 cycles per minute. The current flows through the power cord is the real work current of the sample. After 6,000 cycles, do the insulation withstand voltage test (1000V, 1MIN, 0.5MA).

Demand:

The test must be done for 6,000 cycles and the insulation withstand voltage should be successful.

 

21. Handle Bending Test

Test Method:

1. Turn on the sample at the rated voltage.

2. Bend the handle of the sample for 6,000 cycles

3. Do the insulation withstand voltage test (1000V, 1MIN, 0.5MA).

Demand:

The test must be done for 6,000 cycles. There are no insulation breaking or component damages of the sample and the insulation withstand voltage should be successful.

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