Stainless Steel Ball Pressure Tester IEC60884-1 Clause 25.2 Figure 37
The Ball Pressure Tester conforms to many standard requirements like IEC884-1, IEC950 and so on. It is used for testing the heat resistance of the electrical enclosure and external parts which are made up with the insulating materials. It is applicable to electrotechnical equipment and its subassemblies and components. It is also used for solid electrical insulating materials except ceramics.
|Load||20N±0.2N||Steel ball||Ball bearing steels R2.5mm ISO 3290|
|Material||304 stainless steel||support||Ф50X100 with Ф2.5X25 thermometer hole|
25.2 Parts of insulating material necessary to retain current-carrying parts and parts of the
earthing circuit in position, as well as parts of the front surface zone of thermoplastic material, 2 mm wide, surrounding the phase and neutral pin entry holes of socket-outlets, shall be subjected to a ball-pressure test by means of the apparatus shown in figure 37, except that the insulating parts necessary to retain the earthing terminals in position in a box shall be tested as specified in 25.3.
NOTE When it is not possible to carry out the test on the specimens, the test should be carried out on a piece at least 2 mm thick which is cut from the specimen. If this is not possible, no more than four layers, each cut from the same specimen, may be used, in which case the total thickness of the layers shall be not less than 2,5 mm.
The part under test shall be placed on a steel plate at least 3 mm thick and in direct contact with it.
The surface of the part to be tested is placed in the horizontal position and the hemispherical tip of the test equipment is pressed against the surface with a force of 20 N.
The test load and the supporting means shall be placed within the heating cabinet for a sufficient time to ensure that they have attained the stabilized testing temperature before the test commences.
The test is made in a heating cabinet at a temperature of (125 ± 2) °C.
After 1 h the ball shall be removed from the specimen, which is then immersed within 10 s, in cold water for cooling down to approximately room temperature.
Put the pressure ball on the support, you can make appropriate adjustment at the position of the loaded body according to its oscillation situation. Then twist the loaded body tightly, put the pressure ball on the support again, observe its oscillation situation to ensure adjustment effect.
Only under the condition of equilibrium, the pressure ball can be placed smoothly, otherwise the pressure ball will have obvious oscillation, if use the optical device for testing, it will seriously affect the accuracy of test results.
Method of application:
1. At first, please put the device into the specimen heating box, specimen and loading device are then kept in a standard temperature for 24 hours or after reach to thermal equilibrium conditions, and then do the next test.
2. Then put the specimen which has pretreated before in the middle of the support, and then put the pressure ball in the middle of the support steadily.
3. When reach to exert pressure time of standard requirement, must to remove the pressure ball from vertical side, and then take out the specimen for next test.
1. R2.5 steel ball is ball bearing steels, pay attention to rust protection.
2. The support surface is kept bright, clean and smooth.
3. Prevent foreign bodies blocked the Ф 2.5 thermocouple hole.
4. Prevent balancing weight screws loosen.