Make a battery charger from ATX power supply
Description of the scheme
The components that I added to ATX are highlighted in green. In series with the Voltage regulator, I added a 3.3 kΩ resistor. So I limited the minimum voltage. In series with the 2.7 kOhm resistor, from the first leg, I installed a 4.7 kOhm resistor. So it turned out to limit the maximum voltage. At the output of the power supply, I installed a chain of a diode and a fuse. The result is the simplest protection against polarity reversal. If the battery is incorrectly connected, the current flows through the diode and the fuse is blown. The fan is connected to the power supply of the PWM microcircuit. I installed a 68 Ohm resistor, with a power of 2 watts, to limit excess voltage. The power supply of the microcircuit is about 22 volts.
Basic details
I use Soviet resistors, I found a pair of handles for them.
The indicator screen is a Chinese volt-ammeter – http://alii.pub/5s8fk9
So that’s about the output voltage. I bought the wrong indicator, but it is powered by the measured voltage. Its power supply is from 4.5 volts. Therefore, the voltage tore from 5-6 volts.
Power switch from an old TV.
Install the fuse through the mount. It is a standard car, I will put it at 10 amperes.
I had a board without a case, I found a suitable one.
Power supply ATX conversion into a charger
Marked and cut out all the holes. I painted it from a spray can. I painted what it was, barely enough for the body. All prints are not visible to her.
I installed the board in the case. I screwed on the resistors and a switch.
Installed wires with crocodiles. Double insulated wires, two wires in parallel. Each wire is 0.5 VK. mm. It worked out well.
Oh yes. The minimum voltage in the photo.
Maximum 15.5 Volts. I replaced the voltage regulation resistor, so the output voltage is slightly different from the original.
This is how the unit looks from the side of the mains cable and fuse.
Redesign power supplies to suit your needs. Blocks are now available inexpensively. The schemes are roughly similar. It remains to remove the excess and add the missing. The alteration scheme is relevant for most ATX blocks.
Watch the video