When you repair the power supply part and repeatedly it after replacement, the switch tube burst as soon as the power is turned on. Don' worry, of course, the maintenance expert has , it is not a problem, but the long-term use of this tester can bring you efficiency when repairing the power supply. Save working time! You should first test whether the switching transformer is short-circuited between turns. The test is very simple! Connect the instrument to the 5v power supply, and the tester has been upgraded to use the USB interface of the 5v charger for Android phones, so this test The instrument is not equipped with a power supply when it is sold. The customer should prepare it by himself. Please be aware that the two fish plagues are connected to the winding ends of the transformer coil with a large number of turns. Because all the windings of the transformer are on the same pair of magnetic cores! So as long as there is a group of green lights, it proves that the whole transformer is not short-circuited! It is not necessary to test each group. Note, this tester can only test -frequency with magnetic cores! It can also test step-up with magnetic cores, and can not test power frequency with steel sheets! It can also be tested online, (but the power board is not live! It can be reflected Check whether the output load of the transformer is normal or there is a short circuit. Finally, remove the transformer again and make sure again. If it is still short, you can carefully disassemble the transformer and use the same No. rewinding. -voltage package can also be tested! Test 110v winding Note, this tester can only measure short-circuit between coils! Most -voltage packages are short-circuited coils, but there are also poor insulation or -voltage rectifier diode breakdown. This instrument is insulated Faults and rectifier diode breakdown cannot be detected. Please be aware of this. The tester uses a normal transformer to test the strong state, artificially short-circuit the secondary of the transformer. If the indicator light changes, it proves that the tester is working properly! Material:plastic Package Contents: 1 x Switching Power Supply Transformer