How to detect the regulator diode?
How to detect the regulator diode?
The method of judging an electrode is basically the same as that of judging an ordinary diode electrode.That is,with the multimeter RX1kQ ~ RX10k2 block,first red,black pen arbitrarily connected to the two ends of the voltage regulator,measured a resistance value,and then exchange the stylus and then measured a resistance the resistance value measured twice should be one big and small,the resistance value is smaller,that is,the positive connection method.At this time,the end of the black pen is the positive pole of the voltage stabilizing diode,one end of the red pen is negative.
the difference between the voltage regulator diode and the ordinary diode is basically similar to the shape of a common small power rectifier diode.When the model marks on the shell are clear,they can be identified according to the model.When the model symbol is off,the utility model can be used to distinguish the voltage regulator diode from the common rectifier diode very accurately.1 Low Voltage Regulator Diode. First,the positive and negative electrodes of the measured tube are judged by using the multimeter RX 1kQ.Then dial the multimeter to the RX10K2 block,the black stylus is connected to the negative pole of the test tube,the red pen is connected to the positive electrode of the test tube, if the reverse resistance value measured at this time is higher than that of RX1k2 the reverse resistance of the stopper measurement is much smaller.It is explained that the measured tube is a voltage stabilizing tube; on the contrary,if the measured reverse resistance is still very large,it is explained that the tube is a rectifier diode or a detector diode.High Voltage Regulator Diodes.The high voltage regulator diode can not be directly judged by the multimeter,the circuit shown in Figure 512 should be adjusted such as variable resistance W.The meter needle changes with the variable resistance w there is no steady state for the ordinary diode,and the voltage regulator is the voltage regulator diode and the value of the multimeter is the regulator value of the tube.
Three-pin Zener Diode and Transistor Distinguish Three Pin Regulator Diode is a kind of voltage regulator diode with temperature compensation.Its shell contains two levers a voltage stabilizing diode in series with three pins in the same shape as a transistor.One foot and two feet are respectively the negative pole of the two voltage stabilizing diodes,which can be interchanged at will,and one is connected to the positive pole of the power supply when used,and the other is grounded,the 3 pin is the common positive pole of the two voltage regulators,which is suspended in the air,and is shown in Figure 5-11 as a three-pin Zener diode.The commonly used model is 2DW7,which can be easily identified according to the characteristic of symmetry of 2DW7.First,put the multimeter in RxID or RX100 block,the black stylus connected to the tube of any interest electrode with red pen,in turn,
according to the two electric home B10 resistance values are all hundreds of Europe and more symmetrical,you can initially conclude that the measured tube is the voltage regulator arm,and the black pen is connected to the center pin 3;then put the multimeter in RX10kQ block,the red pen is connected to 3 feet,and the black stylus contact the other two electrodes in turn,if the resistance is very small and symmetrical,it can be further proved that the 9 is the voltage regulator on the contrary,if measured with RX10 or RX100,1,2 feet to 3 feet,although there is a smaller forward electric diode. Said,and the RX 10k file repeated measurements without breakdown ( resistance smaller ) phenomenon, that is,but it is not on the tube. Three-pin zener diode is mainly used in the stability of the temperature stability of the circuit.
Regulating value judgment 1 Direct read voltage regulator value.In some small voltage regulator diodes,the digital value of the upper is expressed as the voltage regulator,in volts ( V ).For example : 7V5,indicating a voltage regulator value of 7.5V.But most voltage regulators can not use this method,such as the model is 2CW55,said the voltage regulator is about 8V,such tubes need to check the transistor parameter manual to know.
Use the multimeter to measure the voltage. A regulated diode with a voltage regulator less than 15V can be measured with a multimeter "RX10k2" block (containing 15V high voltage battery). When reading, the left end of the calibration line is 15V, the most right end is 0V, and the meter 50V (some tables can be used for 10V) to read, and the following formula is obtained: the voltage stability is (50-X) /50X15V., X is the reading of the 50V block scale.The method can accurately determine the diode value below 15V.
Using the applied voltage method to distinguish the steady pressure value.Figure 5-12 shows the applied voltage to determine the regulated value and change the W.
When the V is unchanged,the voltage value indicated is the voltage stabilizing value of the diode. Because R1 and R2 strings are not in danger of electric shock in AC circuit, the power supply can also be replaced by mega ohmmeter.
detection and substitution of voltage stabilized diode
When the diode is damaged, it is difficult to repair. It can only be replaced.
Other models with the same steady voltage value can also be replaced by the common two way tube forward and forward voltage.