1 how to calculate the power?
Answer: power supply usually refers to the total power output, represented by the letter P, the unit is W (Watt), the calculation formula of power for P=U*I power P= output voltage U*, output current of I, such as the power of a 12V1A, the total power voltage 12V* current 1A=12W.
2 power output voltage, output current than the rated current is big, can use normally? Will not damage the device?
Answer: in fact, rated current equipment identification can be understood as the basic working current, that is to enable the normal operation of the equipment, the power necessary selection of current power supply current of the same size or larger. As long as the same as the output voltage, output current of power is greater, the greater the power representative power. The power of the bigger the better (of course, the greater the power the more expensive). For example, desktop computer ATX power supply 300W and 350W or 400W power points, they can be in the computer on the interoperability, the only difference the more you, if computer peripherals, such as mobile hard drives, external burner, high speed graphics, high frequency CPU, TV card and so on, the power only 300W is not qualified, the consequences would be frequent crashes, restart, not normal use, so the supply of a large power is very necessary. From the analysis on the principle, current demand size is depending on the load (i.e. terminal equipment), rather than depending on power supply, power supply can provide only the maximum current. If the horse to the power supply, the carriage to the load, a strong horse and a little horse pulling a cart with the results, one can imagine. Have a friend take the power amplifier and the loudspeaker to compare, say with high power amplifier for driving a small horn, soon burned out, in fact, principle and power audio power amplifier is not the same, the audio frequency power amplifier is amplified voltage type, the output is the exchange (AC) audio signal, audio signal voltage and with the increase of the volume increases, with a small power horn, do not burn just strange, so matching loudspeaker and power amplifier is very important. To sum up, the power supply voltage current favorable, the bigger the better, that the greater the power.OK. but remember not to choose the current than the rated current of small, will be out of the question.
3 what are the functions of switching power supply protection?
Answer: power working in high voltage environment, the lack of corresponding protection function of numerous risks, protect the most basic functions should be: the input circuit protection, output short circuit protection, input over-voltage protection, output over voltage protection, input voltage surge suppression mutation protection etc.. Stone new brand power adapter has more protection function, please rest assured that the use of the vast number of friends.
Power supply 4 of the same specification, some prices are very cheap, why?
Answer: the internal power supply scheme and the use of materials determines the price, the market a lot of power supply for second-hand recycling material production, stock return goods, defective goods, or shoddy work, as long as the power supply has the voltage output of other indicators of whether, even the basic inductive filter circuit are omitted. Or use a simple RCC scheme that is, a transistor as a switch, low efficiency, poor performance, high failure rate, but due to low cost, a lot of cheap power have adopted this scheme is made. The power slightly higher prices are integrated by IC program, the cost is high, but performance is good, high efficiency. All our power are used in the production of IC power management semiconductor manufacturer in the world of the well-known, such as the Taiwan ang Pao, Fairchild etc..
5 safety certificates are those? What is the use?
Safety certificate is imported by the national song, is an important index to measure the quality of the power supply, the 8 country in the world developed has its corresponding safety standards, products are exported to the country, must obtain the relevant safety certificate caixing. As USA UL, Canada CUL, Japan PSE, Taiwan BSS, British LVD, German GS/TUV, European CE, Australia SAA, Chinese CCC certification etc.. To buy the power supply has the certification, the product label printed on both LOGO certification mark the corresponding, beside the logo can be found in a set of code, to the relevant website query certificate of true and false. Or to the supplier to provide copies of product certification, can further verify the true and false. Stone new brand power adapter has passed 3C, CE certification, and other relevant certification also according to customer needs in the application.
6 how to confirm the power output plug is appropriate?
Multiple output DC plug specification, to confirm the specification of the plug you must use a ruler to measure, as long as the measurement of 3 local dimension, the basic can confirm the DC plug specifications, 1 is the outer circle diameter of 2 plug plug, the inner circle diameter, length exposed 3 plug. Such as: DC head 5.5*2.1*12mm diameter circle diameter 5.5mm, inner diameter 2.1mm, length exposed to 12mm. Stone new brand power adapter used DC headers for 5.5*2.1*10, 5.5*2.5*10, the vast number of friends when ordering carefully, lest affect the use of inappropriate DC head. |
