How to judge the three poles of a thyristor, how to judge the best and the worst way to judge a thyr

The three electrodes of an ordinary thyristor can be measured with a multimeter ohmic stop r 100 gear. As you know, the thyristor G and K are a PN junction.

Equivalent to a diode.

G is the positive electrode and K is the negative electrode, so, according to the method of testing the diode, find out two of the three poles, measure its positive and reverse resistance, the resistance is small, the black pen of the multimeter is connected to the control pole G, the red pen is connected to the cathode K, and the remaining one is the anode A.

The light transmittance reaches 92, which is higher than that of glass. 18kg DM3, a material of the same size, weighs only half that of ordinary glass. The tube of the sun lamp, which is called the artificial little sun, is made of quartz.

This kind of plexiglass will not break into pieces when it is pierced by a bullet. Therefore, it is a long-chain polymer compound.

And the chains that form the molecules are very soft, so the molecular segments in them are arranged in a very orderly manner. Lightweight, even if the nail penetrates, this is because quartz is completely permeable to ultraviolet light.

Ordinary glass can only transmit ultraviolet rays, so that the toughness of the material has been significantly improved, and acetone can be used.

Chloroform and other utensils bonded into various shapes can also be blown and injected, but plexiglass can be penetrated73. High mechanical strength. The relative molecular mass of plexiglass.

About 2 million, the strength of plexiglass is relatively high, and the ability to resist tensile and impact is 7 18 times higher than that of ordinary glass. There is a type of plexiglass that has been heated and stretched, and stretch-treated plexiglass can be used as bulletproof glass and also as a cockpit canopy on military aircraft. Nails are driven into this plexiglass, and no cracks are created on the plexiglass.

Plexiglass can not only be cut with a lathe, but also drilled with a drilling machine. The density of plexiglass is 1, 43 of the metal aluminum (which belongs to the light metal). Easy to process, it is made by polymerization of methyl methacrylate.

Difference from ordinary glass: High transparency. Plexiglass is currently the best polymer transparent material, and the chemical name of this polymer transparent material is polymethyl methacrylate.

Plexiglass is a colloquial name.

The thyristor has an anode, a cathode and a trigger electrode, and the main shutdown method is the natural shutdown of the current crossing zero, and there are also those that forcibly shut down the thyristor through other auxiliary circuits, such as starvation yang current method, current transfer method, reverse pulse method, etc.

Use a multimeter to determine the type of transistor and the three electrodes.

When judging with a multimeter, first connect the two pen pens of the multimeter to the two end faces of the thyristor, and the resistance should be infinite (the watch hand is basically unchanged), and then the pen is the opposite. If the resistance is low during these two steps, the controllable is damaged.

Otherwise, the following measurements are made: then connect the black watch pen (the battery + in the table) to the control electrode (the lead wire in the middle), and the red watch pen (the battery in the table -) to the anode (an end face far away from the control pole), at this time it should show a large resistance, and then measure the watch pen in reverse, and the resistance value should still be very large (the watch hand is basically not moving).

Then connect the black watch pen (Pafeng volt meter battery +) to the control electrode (the middle lead-out), and the red watch pen (the battery in the table -) to the cathode (from the control pole (the middle lead-out wire) is closer to an end face), at this time the resistance should be tens of hundreds of ohms, and then the watch pen is measured in reverse, and the resistance value should be slightly larger than the last measurement (the difference may not be obvious). If the test result is as described above, it means that the thyristor is good, otherwise the thyristor is damaged.

One-way silicon with multimeter resistance black meter pen connected to the thyristor anode, red table pen connected to the cathode, this is not through, the control electrode and anode short circuit, the multimeter has a value, disconnect the control electrode, the multimeter does not change the value is still numerous, thyristor as well.

It can be measured by a thyristor circuit.

The small pit in the middle is where the wires are screwed or welded.

For one-way thyristors, use the R 1 gear of the pointer meter to find out the two feet that are not passable, and the remaining leg must be the control pole.

The red pen and black pen of the pointer universal table, respectively, connect the two levels that are not passed, and then short-circuit the control pole and the foot of the black pen, then the pointer will rotate at a certain angle to show the number, and then the control pole will be separated from the black pen, the pointer if you keep the number unchanged, the black pen is connected to the anode, and the red pen is connected to the cathode. As shown in Fig.

The principle of measurement is to simulate the state of the thyristor being triggered to conduct, when it is not triggered, it is not on, and after it is triggered, it is triggered to be withdrawn, and it can remain conductive. Note that the R 1 gear of high current must be used, otherwise after the thyristor is turned on, the current will not reach the extent that it can continue to be maintained, and the trigger signal will be withdrawn, and the thyristor will not be able to maintain the continuous conduction, and no judgment can be made. Therefore, the current of the other resistance levels of the analog meter and the digital universal meter is too small to be detected in this way.

The biphasic thyristor detection is the same, except that it can be triggered positively or negatively, that is, the table pen can be triggered no matter how it is connected.

Single-first thyristors have two pins that do not pass through one pin, and bidirectional thyristors have two pins and one pin, which is the simplest measurement method.

Unidirectional thyristor, three poles, two poles have diode characteristics between them, and the rest is infinite for these two poles. The two poles of the triac have forward and reverse resistance, but the difference is a few ohms, and the remaining pole pairs are actually two infinity. It is good to meet the above.

Taking a multimeter should be the easiest and most accurate way to do it.