V in the machine three terminal voltage regulator (C92 to the ground voltage induction cooker power chip 12a pin voltage ; The black meter rod is grounded The voltage of each pin of the induction cooker power chip 12a , and the red meter rod is connected to the output pin. The 5V of the general induction cooker is the use of 78L05 and 7805 three-terminal regulators.
V In the IGBT base, the third foot of the LM339, the fan input foot, and the four feet of the transformer, one foot is 18V. Third pin of the 5V line, in lineEvery now and then, the panel master IC will be measured.
There is 300V voltage on the main board of the induction cooker, there is no 18v and 5v, check the auxiliary power supply, it should be the auxiliary power supply problem Induction cooker power chip 12a pin voltage . The auxiliary power supply is 18v and 5v, with 18v supplying power to the fan. 5v supplies power to the CPU and keypad. Only when the auxiliary power supply is restored to the voltage each pin of the induction cooker power chip 12a, it is good to check the induction cooker power chip 12a each pinVoltage his part.
The internal cooling fan of the furnace provides 18V DC power. Can not find the appropriate voltage of the fan, the computer's 12V DC fan, a series of cement resistance, about 20Ω/5~10W, connected to the original wiring. There is no fixed support for the computer fan, and the wind tunnel can be locked by the self-made pressure plate. I used this method to solve the problem of several stove fans, and have not been repaired yet.
If the induction cooker is normal, the low-voltage power supply is normal and the fan is provided by the 24V step-down of the host. Common faults electrical high-frequency vibration stop, boiler component failure, overload protection warning sound'> Induction cooker power chip viper12a fourth pin only 9V voltage, where is the problem
1, it may be that the power supply voltage is unstable, or the current is insufficient to cause the electronic components to work normally. Other component problems may be other components inside the induction cooker induction cooker power chip 12a pin voltage problems, such as capacitors, inductors, etc. If there is a problem with these components, it may cause the power chip feedback pin to detect the induction cooker power chip 12a pin voltage is unstable. Specific methods to solve such problems require specific analysis.
2, first turn off the load circuit to measure the voltage, if normal, it indicates that the load circuit is abnormal, check the load circuit. If the voltage is still low after the load is disconnected, it indicates that the power circuit itself is faulty, check whether the components are variable, especially the various electrolytic capacitors and voltage regulator diodes, and finally change the power chip to try.
3, This power supply design has two output voltages, respectively 12V and 5V. Maximum power processing capacity is 10W, output voltage12V. The peak current of the first output is 900mA. However, the second output (5V) is achieved by connecting a linear regulator (7805) and a Zener diode D9 that distributes the voltage drop in series over the first output.
4, the other is between 9V, through 78L05 voltage regulator to the chip sn74hc164 power supply. Note (The 78L05 looks very much like an ordinary low-power triplet. Because the current is small.
5, if the eight-pin integrated block is OK, focus on detecting whether the regulator diode is bad, and the replaced regulator diode must be consistent with the original modelOtherwise, it is difficult to get the original voltage consistency, or no oscillation, of course, the oscillation coil is damaged without oscillation.
First check whether the 300V filter capacitor is invalid, then check whether the 18V and 5V output is short circuit, if there is no problem, replace the viper22a.
①, to the switching power supply voltage stabilizer oscillation thick die chip damage, generally will make the power supply no output voltage, such as: to ten 18V, fifteen 5V if there is no ten 18V voltage first fan drive circuit can not work, the power tube drive circuit can not work and so on. (2) If there is no 15 V voltage, first of all, the CPU microprocessor chip has no power supply so that the chip can not work, etc., it can be said that the 18 V, 15 V voltage is not, so that the whole machine can not work completely.
If you are confirming that this eight-pin integrated block is OK, focus on detecting whether the voltage regulator is bad, and replace the voltage regulator diodeBe consistent with the original model, otherwise it is difficult to get the original voltage is consistent, or can not oscillate, of course, the oscillation coil is damaged without oscillation.
This is the control power supply circuit is not working properly. Check whether the load is short circuit or overload, then check the control power circuit, and change the chip when necessary.
Generally 5V, 12V, 18V. chks007 is the CPU pin number used in Midea induction cooker description Input/output (I/O) operating voltage value (V). SURGEI Surge Detection 10. PORTD2I/O bit programmable input/output 47. EXPO bit programmable output 0.72. PORTC2/IN-PHASEI/O bit programmable input/output or synchronous detection input port 0.
This is a key failure. The machine of the touchpad is bus control, the normal bus pin 3 is 5V, and the normal bus pin 4 is 5V. If the voltage is abnormal, check the pull-up resistance and the integrated block.
ElectromagnetismNo matter what the fault of the furnace, after replacing the components, be sure not to rush to connect the wire reel test machine, otherwise it will cause burning IGBT and safety tube, and even the rectifier bridge. Should be in the case of no wiring disk, power test each point voltage, such as 5V, 12V, 20V (some 18V, 22V), and drive circuit output wave type (normal is square wave), you can also use a digital multimeter 20V file test (normal voltage fluctuations).