Detailed explanation of car battery charging circuit diagram

Car battery charging circuit diagram (I)

Circuit principle: The circuit charges the battery after voltage transformation, bridge rectification and conditioning. The transformer can adjust the charging current. It can charge a battery of about 12v 100AH. According to the 10-hour charging rate, a charging current of 10A is required. A 150VA transformer is required, the secondary AC voltage is 15V, and the current limit is 10A. There are corresponding transformers that transform the power to AC 10V, and use full-bridge rectification plus large capacitors to stabilize the power to 14.14V.

This is an over-temperature and under-temperature alarm composed of CD4011 four-NAND gate integrated circuit, which is used to monitor the temperature of the constant temperature box. When the constant temperature circuit fails or the power is off, and the temperature in the box is higher or lower than the allowed range, it can sound an alarm to remind people to take corresponding measures. The circuit has a resolution of 0.1℃.

Diodes VD1 and VD2 are placed in a constant temperature box. When the temperature in the box is lower than the lower limit, the potential at point a in the figure is greater than the threshold voltage U at the input end of gate A, and the output end of gate A is low, so that gate B outputs a high level. At this time, the multivibrator composed of gates C and D starts to oscillate, and the piezoelectric piece emits an alarm sound; when the temperature in the box is higher than the upper limit, the potential at point b is less than the threshold voltage U of gate B, which can also make gate B output a high level, and the piezoelectric piece YD emits an alarm sound. Only when the temperature in the box is between the upper and lower limits, YD will not make a sound. The lower and upper limits can be changed respectively by adjusting the values ​​of RP1 and RP2. The power supply circuit is an AC/DC dual-purpose power supply, and E is a backup power supply. When the AC power supply fails, VD3 is turned on, and the backup power supply supplies power to the circuit. Since this circuit consumes very little power, the backup power supply can use stacked batteries to reduce the volume.

Car battery charging circuit diagram (II)

Parts List:

R1=1 resistor

D1 = 1N4001 rectifier diode

T1= 220V/17V 4A Transformer

R2 = 1.2K resistor

D2 = 6.8V 0.5W zener diode

LD1= Green LED Green light emitting diode

R3 = 470Ω resistor

TR1 = 4.7K resistor

LD2= LED Red Light Emitting Diode

R4 = 470Ω resistor

Q1 = BTY79 6A SCR thyristor

Q2 = C106D SCR thyristor

M1= 0-5A DC ammeter

R5 = 10K resistor

C1 = 10uF 25V capacitor

GR1= 50V 6A rectifier bridge

F= 5A Fuse