IEC 60884-1 Clause 12.3.11 Switch Life Tester Screwless Terminals Electrical And Thermal Stresses Test Apparatus

IEC 60884-1 Clause 12.3.11 Screwless Terminals Electrical and Thermal Stresses Test Apparatus

Standard: IEC60884-1 clause 12.3.11.

Application: It is used to check whether the screwless terminals can withstand the electrical and thermal stresses occurring in normal use.

Test sample: Plugs and socket-outlets screwless terminals.

Feature: The device is easy for operating, the load current is stepless adjustable,,the sample fixture will be manufactured according to the standard requirements.

Technical Parameters:

Test processes:

Screwless terminals shall withstand the electrical and thermal stresses occurring in normal use.
Compliance is checked by the following tests a) and b), which are carried out on five screwless terminals of socket-outlets which have not been used for any other test.
Both tests are carried out with new copper conductors.

a) The test is carried out loading the screwless terminals for 1 h with an alternating current as specified in table 10 and connecting rigid solid conductors 1 m long having the nominal cross-sectional area as specified in the same table.

    The test is carried out on each clamping unit.

    During the test the current is not passed through the socket-outlet, but only through the terminals.
    Immediately after this period, the voltage drop across each screwless terminal is measured with rated current flowing.
    In no case shall the voltage drop exceed 15 mV.
    The measurements are made across each screwless terminal and as near as possible to the place of contact.
    If the back connection of the terminal is not accessible, the specimens may be adequately prepared by the manufacturer; care shall be taken not to affect the behaviour of the terminals.
    Care shall be taken to ensure that, during the period of the test, including the measurements, the conductors and the measurement devices are not moved noticeably.

b) The screwless terminals already subjected to the determination of the voltage drop specified in the previous test a) are tested as follows.      

    During the test, a current equal to the test current value given in table 10 is passed.

    The whole test arrangement, including the conductors, shall not be moved until the measurements of the voltage drop have been completed.
    The terminals are subjected to 192 temperature cycles, each cycle having a duration of approximately 1 h and carried out as follows:

    – the current flows for approximately 30 min;

    – for a further period of approximately 30 min no current flows.

   The voltage drop in each screwless terminal is determined as prescribed for the test of a) after every 24 temperature cycles and after the 192 temperature cycles have been completed.
    In no case shall the voltage drop exceed 22,5 mV or twice the value measured after the 24th cycle, whichever is the smaller.
    After this test an inspection by normal or corrected vision without additional magnification shall show no changes evidently impairing further use such as cracks, deformations or the like.