Experiment

Test Method and Description

High Temperature

Storage/ Dry Heat

The specimen shall be subjected to 150 ± 2℃ for 1000 ± 12 hours in a thermostatic

bath without load and then stored at room temperature and humidity for 1 to 2 hours.

Therefore, the change of varistor voltage shall be measured.

Step

Temperature

Period

1

-40±3

30Min±3

2

Room Temperature

1 hour

3

125±3

30Min±3

Temperature Cycle

The temperature cycle of specified temper

-ature shall be repeated five times and then

stored at room temperature and humidity for

one or two hours. the change of varistor

voltage and mechanical damage shall be

examined.

4

Room Temperature

1 hours

High Temperature Load/

Dry Heat Load

After being continuously applied the maximum allowable voltage at 85 ± 2℃ for 1000±

2 hours, the specimen shall be stored at room temperature and humidity for one or two

hours, Therefore the change of varistor voltage should be measured.

Damp Heat Load/

Humidity Load

The specimen should be subjected to 40± 2℃, 90 to 95﹪ RH and the maximum

allowable voltage for 500 hours and then stored at room temperature and humidity for

one or two hours. Therefore the change of varistor voltage should be measured.

Low Temperature

Storage/ Cold

The specimen should be subjected to -50 ± 2℃, without load for 500 hours and then

stored at room temperature for one or two hours. Therefore the change of varistor

voltage should be measured.

Direct contact

electrostatic discharge

1.Discharge: contact electrostatic discharge; 2.Voltage：8KV（Level4）

3.Polarity：+,- ; 4.Number: 10 times ; 5.Interval time：1sec

Direct air electrostatic

discharge

1.Discharge: air electrostatic discharge; 2.Voltage：15KV（Level4）

3.Polarity：+,-; 4.Number: 10 times; 5.Interval time：1~ 3sec

IEC61000-4 Standard

SEVERITY

LEVEL

AIR

DISCHARGE

DIRECT

DISCHARGE

1

2 KV

2 KV

2

4 KV

4 KV

3

8 KV

6 KV

4

15 KV

8 KV

SMD Transient Voltage Suppressors

Reliability Experiment