AS/NZS 3112:2011 Clause 22.214.171.124 Force for pin bending tester
126.96.36.199 Pin bending test
All flat pins of plugs rated up to and including 15 A shall be subjected to a pin bending test.
Three sample plugs not subjected to any previous tests shall be tested as follows:
Pins of assembled plugs shall be tested by clamping the plug in a rigid holding block and applying a bending force, as shown in Figure 2.8, to the pin under test.
The pins shall be straight at the beginning of the test. If there is any doubt about the straightness of the pin, it shall be checked by the appropriate plug gauge shown in Appendices A, B or F.
The point of application of the force shall be 14 ±0.5 mm from the face of the plug.
The direction of the force shall be along a line parallel to the face of the plug.
Active and neutral pins shall be forced towards the centroid of the plug and then back to the starting point. On the first sample plug, any earth pin shall be forced but in one direction only and then forced back to the starting point. On the second sample plug, any earth pin shall be forced in the opposite direction to that used for testing the first sample plug. On the
third sample plug, any earth pin shall be forced in the direction that gave the least favourable result during testing of the first two sample plugs.
NOTE: This is intended to simulate damage that may occur when a plug is walked on and bent
pins are straightened.
The distance moved from the point of application shall be 7.5 ±0.3 mm, and then the pin shall be forced back to the starting point. Any ‘spring-back’ is ignored.
NOTE: ‘Spring-back’ means that the pin is allowed to move back to a position less than the travel distance, when the force is removed.
The travel from the starting point to the end point (7.5 mm) and back to the starting point is one cycle (i.e. one cycle is two separate movements).
The speed of deflections shall be a maximum of 50 mm/s, without intentional delay between consecutive movements within each cycle.
The interval between successive cycles shall be a minimum of 10 s.
The duration of one cycle shall be a maximum of 60 s.
The pins shall be tested for 20 complete cycles.
After the tests the pins shall be inspected with normal or corrected to normal vision.The pin shall not be broken off.
NOTE: Cracking of the pin, less than full thickness, is not deemed to be broken off.If in doubt, pins shall be disassembled from the plug and any insulation removed.
NOTE: In some cases the break may be below the face of the plug or the insulation may hold the broken pieces together, retaining electrical contact.
Figure 2.8 Application Of Force For Pin Bending Test AS / NZS 3112
|dimensions of plugs
|apparatus for flexing test
|form of pin
|dimensions of insulation on insulated live pins
|pressure test apparatus for insulation on insulated plug pins at high temperature
|impact test apparatus for insulation on insulated plug pins at low temperature
|abrasion test apparatus for insulation on insulated pin plugs
|application of force for pin bending test
|mounting of plug for temperature rise test
|pin clamping unit for the temperature rise test