Electric vehicles have quickly entered our lives with their advantages of convenient travel, low carbon and environmental protection, but their chargers have a high failure rate, which is very troublesome. Because the price of the charger is not too high and the maintenance is complicated, many car owners just discard it and do not repair it. In fact, it is not difficult to repair electric vehicle chargers. This article will briefly introduce the repair methods of electric bicycle chargers, and how to deal with common faults of electric vehicle chargers, so as to provide you with reference. Electric vehicle charger fault repair method
First, the power indicator light is on when charging, and the charging indicator light is orange
First of all, please Check whether the output plug of the charger and the charging plug of the battery box are firmly inserted. If there is no problem, check whether the fuse tube above the battery box is open or the fuse holder is loose and has poor contact. In addition, some models need to open the battery lock before charging. If the above faults are eliminated, consider whether the output line of the charger is open. You can use a multimeter to measure the no-load output voltage of the charger (200V gear). , if not, it may be that the output line of the charger is open, turn the charger on, and change another output line to eliminate the fault. Note: When replacing the output line of the charger, be sure not to reverse the positive and negative poles of the original machine.
Second, the power indicator is not on, and the charging indicator is not on
Check whether the input power plug of the charger is well connected to the mains, Plug the charger input plug into a normal power outlet and try it out. If the situation remains the same, open the charger shell and observe whether the fuse inside the machine is broken. After the input line fails, check whether the components near the high-voltage area on the circuit board are soldered, and whether the fuse holder is in poor contact. Focus on checking whether the transformer T1, transistors V1, V2, etc. In addition, the open circuit of R5 or R6 will also cause the above-mentioned faults. If the fuse in the machine is broken, do not replace the high-ampere fuse tube (the fuse tube of the charger is generally 2A), and should focus on checking D1-D4, V1, Whether V2, R4, R7 and D15, D21 are damaged, if damaged, can be replaced with the same type. Please note that when the above components are damaged, one or two may be damaged at the same time, and sometimes several may be damaged at the same time. During maintenance, you need to check and replace these components one by one before powering on.
Three, serious heat generation, and even the shell is burned and deformed
This is mainly caused by the looseness of some components caused by the fact that some users often carry it with the car. The main manifestations are: when C18 is loose and soldered, it will cause V1 and V2 to work abnormally, and the heat will be very large. In severe cases, the charger shell will be deformed, and the circuit board will be scorched, resulting in damage to V1 and V2. C18 can be re-soldered and checked. V1, V2, R4, R7. If the fault still cannot be eliminated, it is necessary to check whether there is an open circuit in D15 and D21. In addition, some manufacturers use a double diode for the output rectifier, and one of the open circuits also causes the above fault. Sometimes the fault will cause V1, V2. one damaged. It needs to be checked and replaced at the same time.
Fourth, the heat is large and accompanied by abnormal noise
The cause of the failure is the damage of the output stage vibration-absorbing resistor-capacitor R31 and C17. In addition, C12 open circuit or virtual welding can also cause the above faults.
5. There are abnormal noises when working, and the battery cannot be charged
Check whether the C8 on the circuit board is soldered or damaged. Generally, replacing the C8 can be done. solve.
6. There are abnormal noises during work, and the power indicator and charging indicator are dim and flashing
The reason for the failure is that the IC1 is damaged. Be careful when replacing it. Do not damage the copper foil of the printed board. After the replacement is normal, adjust R28 to make the output voltage of the charger within the normal working range.
Seven, the output voltage is very high
The output voltage is very high (greater than 50V), the cause of the failure is the short circuit of C15 or the open circuit of R26. Measure the voltage of “1” pin of IC1 integrated circuit.
Note: After replacing R26, R28 should be readjusted to keep the output voltage of the charger normal.
8. The output voltage is normal, but the charging current is very small
Check whether R30, R11, R13 are in poor contact or damaged, if they are normal, please replace IC1 Troubleshootable.
Nine, the output voltage is normal, the charging indicator has no indication or the indication is incorrect
It is usually due to IC2 damage or LED2 damage, which can be replaced.
10. The copper foil of the output part is blown out
After turning on the charger, it is found that the copper foil of the output part of the charger is blown out, which is usually the positive and negative of the battery. As a result of extremely reversed connection, the resulting failure will cause damage to many components of the charger. If the charger fuse is not broken, usually replace R30, IC1, IC2 and connect the broken copper foil to return to normal. If the fuse of the charger is broken, the fault is more serious. D1-D4, V1-V2, R4, R7, etc. may be damaged, and need to be replaced one by one after measurement.
Common faults of electric vehicle chargers
1. The power supply does not start: plug in the power supply, the large capacitor has a voltage of 300V, unplug the power supply and measure the 2-terminal of the large capacitor or the 300V voltage does not drop. After discharging the capacitor, replace the starting resistor. The starting resistance is in the power input part, the resistance value is 150K, and the power is 2W.
2. The power supply does not start: plug in, there is a 300V voltage at the 2 terminals of the large capacitor, unplug the power supply, the voltage of the large capacitor drops slowly, check all the circuit boards for desoldering phenomenon, and the repair welding is completed After that, replace the 3842 with a new one, and then power on and test the machine.
3. Flashing light: first repair the circuit board and test the machine again. If the light is still flashing, please check the output sampling resistance. 0.1 Euro. 3W power. Connect it to the negative terminal of the output line and replace the resistor with a new one.
4. When the output voltage is high, the voltage is higher than 70 V when the power is turned on, and the lamp does not turn on after charging. First, repair the circuit board and test the machine again. If the voltage is still high, please replace the photocoupler, Test the machine again, or the output is high, replace the 431 reference voltage regulator, and test the machine again.
5. Squeaking, heating, insufficient charging: measure the voltage of the large capacitor when it is powered on, as long as it is lower than 300V, the general capacitor is invalid and can be replaced.
6. Serious fever, please replace the fan with a new one.
7. If the output voltage is unstable, first repair the circuit board, then test the machine, and then replace the output capacitor 63V470UF capacitor for a new test machine.
8. If the charging does not turn the light, use the detector to test the data, and then replace the 358 or 324 with a new test machine.
9. The charging is unstable, sometimes it can be charged, and sometimes it cannot be charged. Use the tester to detect various data, then replace the input and output power cables, and repair the circuit board to test the machine.
10. Power on and burn the insurance: first check whether the power tube has broken down. If not, replace all 4 rectifier diodes and test the machine.
11. There is no output after power-on, power-on test machine, there is 300V voltage at the 2 end of the large capacitor, and it slowly drops, first check whether the large diode at the output end breaks down, repair welding, and test the machine again.
12. Two red lights are on when power is on: test the machine when it is powered on, check whether the no-load voltage is normal, and then replace the 358 or 324 for a new test machine.
13. If there is no output after power on, it can start normally, and the indicator light is normal. First, replace the output line with a new one. For chargers with relays, directly short-circuit the relays and test the machine.
14. When the flashing light is turned on, please repair and solder the pins of the transformer, and then test the machine. If the same, please check whether the 431, photocoupler, and each diode of the output part are short-circuited, whether the transformer core is loose, and whether the power supply Whether the 10 ohm small resistance of the input part is open circuit. Or replace the 3842 and try the machine again.
15. If the light does not turn on when charging, first use a tester to check the data. Generally, the voltage of a new battery is not higher than 59.5, and the battery is not higher than 58.8 after charging for half a year, which is normal. It may be higher than this voltage. Do not turn lights.
16. Low output voltage: repair the circuit board. Test the machine, then replace the input and output large capacitors with new ones and test the machine again.
17. The output is low and it is hot. If the output voltage is lower than more than 40 V, and the power tube and the transformer are hot, it is generally a problem with the transformer.
18. It is difficult to start, sometimes it can work and sometimes it can’t start, repair the circuit board, and then test the machine. If still, please replace the small capacitor of the input part and try the machine again, 50V47UF.
19. After burning 3842, 3842 and replacing it with a new one, the test machine is plugged in and hear a clicking sound. This is to measure the voltage of the 2 terminals of the large capacitor at 300V and slowly turn it on, indicating that the 3842 has broken down again. Make up for it first. Solder the circuit board, check whether the transformer pins are loose or the leads are disconnected, whether the large diode of the output part is open, and whether the circuit board is broken.
20. The above faults are suitable for the common faults of most single-tube circuit chargers on the market, and the technicians can be consulted at any time during the operation.
How to judge the performance of the charger
Such as 48V charger, the maximum voltage is not more than 59.6V, if it is higher than this voltage, the charging may not turn on the light, and the low voltage is not lower than 55V, if the voltage is lower than this voltage will cause insufficient charging , it is easy to drain the battery for a long time. Current, such as 48V20A charger, the maximum current is not more than 3A. More than 3A may cause the battery to lose water earlier, and the minimum is not lower than 2.1A. Low voltage this current causes insufficient charging.
Precautions for the use of electric vehicle chargers
1. 48V new battery requires charger parameters, the highest voltage is 58.5—59.7, not less than 58V, low Insufficient charging at 58V, higher than 59.7V may cause the lamp not to turn on. Turning light current is about 0.4—0.7A, and actual voltage is about 55.5V. If it is lower than 50V, it will cause insufficient charging, and the battery will lose power after long-term charging.
2. The 4820 battery requires a maximum charging current of 2.4—-3.3A. If it is lower than 2.2A, the charging is slow and the charging effect is poor.
3. The actual power of the chargers less than 30 yuan on the market is small, and the parameter design is not accurate, please pay attention to the distinction.
4. The failure of the voltage regulator circuit of the charger will cause the output voltage to be 75—130V, and the rechargeable battery will be hot and the light will not turn.
5. When a new battery appears, the cruising range of 20A battery is less than 30 kilometers, and the cruising range of 12A battery is less than 25 kilometers. Please check the parameters of the charger. If you can’t judge it, please replace it with a high-quality charger and use it again. to solve the problem.
6. When the new battery does not turn on the light, please replace it with another high-quality charger to test the machine.
7. Under normal circumstances. The charging time of 4820 new battery is about 10 hours, and the cruising range is 40-60 kilometers. The charging time of 4812 new battery is about 10 hours, and the mileage reaches 25-40 kilometers. If the normal charging time exceeds the above, please replace the high-quality charger use again.
8. There are many chargers’ internal circuits, and the input and output connections are aging, resulting in sometimes being able to charge and sometimes not being able to charge. Seriously affect the battery, or the circuit fails during the charging process, causing the charging drum. If this happens, please directly replace the high-quality charger and use it again.
Electric vehicle chargers are best not to be universal
Many friends are asking whether electric vehicle chargers can be universal. Some answers are possible, some are not. Who do you listen to? Buying.com suggestion: It is best to use a charger that is matched with an electric vehicle battery. Because in general, the charger is configured according to the size of the battery of the electric vehicle, that is to say, the size of the current and the size of the voltage. Under normal circumstances, electric vehicles, four-wheeled electric vehicles, and electric sightseeing vehicles and electric patrol vehicles are all 18v or 72v with certain specifications. However, the capacity units of electric vehicle batteries are not necessarily the same. Therefore, it is recommended that you use the matching electric vehicle charger. Of course, we know that battery charging is related to charger voltage rather than current. If the charger is not converted for a long time or the voltage of the charger is too high, the battery will lose water and the battery will bulge. The effect of current on the battery is how fast it charges the battery. But it will charge the battery of the electric car. Therefore, it is not impossible for electric vehicle chargers to be universal, but it is best not to be universal.
