How to repair the electromagnetic stove explosion machine
Rectifier bridge is normal (with Multimeter diode file test): A: multimeter, red pen, "-", black pen "+", there is about 0.9V voltage drop, tune, no display. B: multimeter, red pen, "-", black pen, respectively, two input, there are about 0.5V voltage drop, the tune is not displayed. C: multimeter, black pen, "+", red pen, respectively, two input, there are about 0.5V voltage drop, "tone", "no" display. 5. check the capacitor C301; C302; C303; whether the heat damage. (if the damage has been deformed or burned) 6. detects whether the chip 8316 is broken: measurement method: measuring 8316 pins with a multimeter requires 1 and 2; 1 and 4; 7 and 2; 7 and 4 cannot be shorted. Is the thermal switch insulation protection damaged at 7.IGBT?. Key action detection, measuring whether the CPU line breakdown;
(1) if the bulb is dark red. (applicable to plug 220V standby indicator), open the electromagnetic oven power, the bulb flicked on and off, (and plug in the 220V after the standby indicator does not light), open the electromagnetic oven power, a light bulb that is dark is a dark light power resume shows; the electromagnetic oven has the basic OK. 2. if the bulb is bright, it indicates that the IGBT pipe is fully connected. At this point, if the light bulb is removed, the IGBT tube must be burned! It should be the main driver of resonant capacitor voltage rectifier circuit. (3) if the bulb is dark red, open the electromagnetic oven power, lighting brightness unchanged. It should be the main control panel power supply side power circuit of microcomputer. (4) if the bulb is dark red, open the electromagnetic oven power, a light bulb of a secretly flashing, but the pot up light bulb is very bright; to lift the pan fried IGBT, check the CPU disk drive line. The electromagnetic oven simple circuit board maintenance method; circuit board burn IGBT or fuse maintenance procedures or IGBT current fuse burned, can not immediately change the parts, must confirm the following other parts are in normal state to replace, otherwise, IGBT and fuse will burn. 1. visual current fuse whether burned 2., check whether IGBT breakdown: use multimeter diode file to measure the IGBT "E"; "C"; "G" three poles whether breakdown. A: "E" is extremely close to "G"; "C" is extremely "G", and both positive and negative tests are not normal (normal). B: multimeter, red pen, E, "extremely", "black pen", "C", there are about 0.4V voltage drop (model GT40T101, three poles completely blocked). 3. measuring whether the transformer is broken or not, the normal state is as follows: measuring the resistance of the transformer with a multimeter, the secondary resistance is about 80, and the initial is 0 ohms.
First, check the fuse, rectifier bridge, IGBT power tube is normal, if not normal, replace it (not eager to pass the test machine), and then check the power supply voltage 300V, 18V and 5V is not normal.1 repair IGBT tube electromagnetic oven fear trick; also remember to replace the IGBT drive tube change together (whether it is good or bad; many people have bad measurement did not change; the price is not too long to burn IGBT; two audions up to 1 yuan; a IGBT to turn over ten) also check the 0.27UF or 0.3UF, 5UF capacitor; everything is ready. 2 in the exchange of 220V, a series of 60-100W lighting, and pan, turning on the power supply:
