6V and 12V Car Battery Charger Circuit Design Diagram
The initial charge current should be adjusted via the TR1 to 1.2A. The adjustment can be done with a 6V battery. Connect in series with the battery a current [maximum 10A]. If there is 6V battery is short-circuited through the ammeter the charger terminals and adjust the TR1 current to 1.2A. When setting the switch S2 should be in the position of 12V, i.e. open. Particular attention should be paid to the accuracy of the diodes D2 and D3 because they protect the battery from overcharging. If the differential voltage is 100mV to go to consider them as acceptable. If you encounter difficulties in the current setting and the TR1 is not enough, you can change the value of the resistor R4, to measure charge current 1.2A. The two parallel resistors constituting R10, should be placed at a distance from the printed and Q5-6, because heated. The bridge B1 and Q5-6 be mounted on heatsink having insulated electrically from this with suitable mica silicone.
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