Wednesday, December 29, 2010
Weak current college】 【select electric iron power and use principles】.
<br> ① welding integrated circuits, transistors and other components of the heating wearing parts, considering the selection of 20W or internal heat-25W thermal-electric iron. <br> <br> ② welding thick wires and coaxial cables, considering the selection .of the heat-50W or 45-75W thermal-electric iron. <br> <br> ③ welding large components, such as metal chassis grounding lug, suffer more than 100W electric iron. <br> <br> From there on, electric .iron, 20W, 25W 35W, 45W, 75W, 100W and 500W, and other specifications. Enthusiasts generally use the internal thermal 25W electric iron. <br> <br> Electric iron initial use, first to soldering head hanging Tin, for later use .soldering and welding. Hanging Tin is simple, power-up before using sandpaper or a knife to clean up the tip end, power, the question on the occurrence of the temperature rise to a certain extent, the solder on the occurrence of the melt, .the tip on the end hanging on a layer of Tin. After hanging Tin soldering iron, you can use to welding. <br> <br> Used electric iron welding, apart from must have a solder bar do solder, directly used for welding, .flux should also be available. Flux welding, as the name implies is helpful, it can clean the welding surface and remove soluble impurities in Tin, improve the weld quality. Commonly used with rosin flux and solder paste (commonly known as welding oil), .in which a corrosive Rosin is a small natural resins. Solder bar (also known as the solder wire), commonly known as with Rosin, Rosin core solder bar. Solder paste is also a very good flux, but its corrosion resistance strong, is itself .not an insulator, it is not appropriate for components of welding, mostly used for larger welding of metal elements, usage should not be too much, welding completed should use alcohol cotton balls will be welded parts of clean, preventing corrosion residue of solder joints and .welded fittings, impact on product quality and longevity. <br> <br> In addition, using soldering is strong electric operation, be sure to note the safe use of electricity. Any soldering must have three terminals, two of which touches with the soldering .iron core, used to connect 220V AC power, another is linked with the soldering iron shell grounding protection Terminal to connect the ground wire, for security reasons, it is best to use multimeter before using a soldering iron-core is identifying the broken line or .mixed line. 20 ~ 30W of General Electric iron core resistance of soldering iron: 1500-2500 ohm. <br> <br> Welding is each electronic enthusiasts must master the basic skills, so must the following some efforts and have a good practice. .How can the welding fine components that? simple, you should be aware of the following three points. <br> <br> 1. welding, should be a component of the leader after truncating the excess portion hanging Tin. If the component is not .easy to hang on the surface of the Tin oxide, you can use the fine sandpaper or a knife to clean up the wire surface, using soldering iron with just the right amount of rosin core solder to hang the XI-leader. If you still can .'t hang up Tin, component leader in Rosin block, and then gently with a soldering iron, while turning the contact wire, wire surface leader can even hang. Each leader hold-time should not be too long, generally to 2 ~ 3 seconds .should avoid hot bad elements, especially enabling to diode, triode pin hanging Tin, it is best to use metallic pliers leader rely on Shell's part to pass away part of the heat. In addition, the various components of pins do not cut too short, .otherwise it is not conducive to the heat, did not facilitate soldering. <br> <br> 2. welding, to the hook-up wire placed question welding components, such as printing plates have pads in the holes or various connectors, sockets and .switches have to lug holes, was stained with just the right amount of Tin soldering iron in welded joints stay 3 seconds after the soldering away, the welding point forming a smooth solder joints. In order to guarantee the best quality welding was, in welding components .lead to location prior to hang also Tin. Welding time to ensure that the leader position does not change, otherwise very easy to produce virtual welding. Tip over time should not be too long, too long will hot bad elements, too short for welding melting .insufficient cause false welding. <br> <br> 3. welding, to carefully observe the solder joint shape and appearance. Should have a half-spherical joints and height slightly less than the RADIUS should not be too drum or is too flat, smooth ., uniform appearance should, no apparent porosity or depression, are easily soldered or false welding. Simultaneous welding solder joints in a few components of the leader, the more you should be aware of the quality of the solder joint. <br>.