Power Supply: noise filter circuit, rectifier

Effects components: 

F1 : Fuse overcurrent protection, when the phenomenon of slow flow through F1 sources make up, it will melt the fuse wire, disconnect power supply to protect the components from damage more. TH1 : Fuse overvoltage protection, which is composed of one pair of adjacent semiconductor, maximum voltage between 230V-270V on it (depending on the type of source). When the input voltage is too high or lightning voltage leads to increased TH1 put on, this will break adjacent to disconnect the power supply voltage level. CX1, CX2 : Capacitor input filter, short circuit the industrial impulse noise greater frequency. LF1 : Inductors, prevent impulse noise frequencies not reach the source. RV/C3/C3 : RC type filter circuit to create escape routes for the high-frequency pulses. D1-D4 : Circuit bending demand change AC voltage of the power supply into DC voltage. C5/C6 : source filter capacitors, voltage leveling circuit after straightening. R1/R2 : resistor voltage balance on the 2 capacitors. SW1 : Switch changes input voltage. 220 - breaker, 110V - plays AC line fuse to go through, the noise pulse knocked down by CX1/LF1 to RV.Filter circuit includes RV/C3/C4 will continue to eliminate interference industrial remnants. In other words, the AC adapter needs to have cleaner. Because alternating current is constantly changing voltage on the adapter should be changed. For example selling period 1 A (+) / B (-), sale of any 2 A (-) / B (+) ... If the input voltage is 220V (SW1 off). Upon A (+) / B (- ) , the D2/D4 diode is forward bias, the current passing from point A through D2, charging the capacitor pair C5/C6, through mass downloading, return to point B through D4, closed circuit. Upon A (-) / B (+)is the D1/D3 diode is biased, current flow from point B through D3, charging the capacitor pair C5/C6, through mass download, through D1 back to point A, closed circuit. So, with the second period of an alternating current sales are generated through load currents from top down. Voltage capacitor pair will be placed on the positive (+) at point C, negative (-) at point D (mass). Voltage on C5/C6 values ​​are: - (220V-2x0.7) x sqrt2 = 309.14 V (if using silicon diode, diode voltage drop on each ~ 0.7V) - (220V-2x0.3) x sqrt2 = V 310.27 (if using germanium diode, diode voltage drop on each ~ 0.3V) If the input voltage is 110V (SW1 closed) When A (+) / B (-) , the D2 is biased, current flow from the A through D2, loaded the C5, the B closed circuit. Value of the voltage across C5 is: 110V-x0.7) x sqrt2 = 154.57 V (by just over one diode voltage drop) When A (-) / B (+) , the D1 is forward-biased, current flow from loaded the C6 point B, through a closed circuit of D1. Voltage on C6 value is: (110V-x0.7) x sqrt2 = 154.57 V (by just over one diode voltage drop). The total voltage on C5/C6 will be: 154.57 x 2 = 309.14 V 1 pm This is the primary source of supply for all power circuits, the workers usually call you on point A voltage is 300V voltage, of course However it is not known exactly in terms of value.

 damaged in the circuit:





















Phenomenon 1 : Orphans fuse - Due overvoltage, lightning. Instead of the right type. Phenomenon 2 : Orphans fuse, replace the back off. - Because convolution 1, 2, 3 or even 4 diode bridge adapter. When measuring the resistance that forward / backward of them all ~ 0Ω. Rather. - As one of the convolution filter capacitor. Measure will see their resistance by 0Ω, replace. However, the cause of this happening is extremely low (1% probability.)Note: 1 Some sources also have torpedo tubes (shaped ceramic capacitors) overvoltage protection following parallel fuse F1, when lightning voltage rating or higher, it will increase the short-cut lines and cause fuse F1. If the source uses this kind of protection, we have to check measurements, impedance is replaced by 0. Phenomenon 3 : Point A low voltage from 220V-250V. - Due to 1 or even 2 dry filter capacitor. Rather. When dry convergence phenomenon often accompanies the machine will not start or boot, but reser, hanging by the source at the time were not carefully filtered, and the resulting output AC ripple is.