I. "Test Standard" for SMD self-recovery fuse.
(1) the test environment is room temperature at 25℃, without light and heat radiation;
(2) The initial internal resistance Rimin of the fuse must be within the scope of the specification;
(3) The fuse remains inactive for 15 minutes under Ihold current, and is judged as qualified;
(4) The fuse operates within 5 minutes under Itrip current, and is judged as qualified;
(5) The internal resistance R1max of the fuse after operation shall be within the scope of the specification;
II. "Test Process" of SMD self-recovery fuse.
(1) initial internal resistance Rimin measurement: unpack, take out the fuse, and measure the internal resistance of the fuse;
(2) Welding: The fuse is soldered on the PCB by reflow, and leads are connected on the PCB to facilitate the electrical performance test;
(3) hold current Ihold test: select DC constant voltage constant current source for testing. Adjust the voltage to the specified voltage Vmax, adjust the current Ihold to the specified current Ihold, and energize for 15 minutes;
(4) Itrip test of operating current: select DC constant voltage constant current source for test. Adjust the voltage to the specified voltage Vmax, adjust the current Itrip to the specified current Itrip, and power on for 5 minutes;
(5)R1max test: cool the fuse after action for 1 hour, and measure the internal resistance of the fuse;
