The charger plug has a voltage cutoff switch in it. If you want to bypass it, take it out, but I wouldn't recommend it. It's easier to regulate down than up.Maybe, but the battery has smarts to protect it, but why didn't they put a proper power supply in it that would regulate to the correct voltage. Like everyone else does. Its all about price.
The regulator I used will supply a rock solid regulated 13.6 volts, no matter what you throw at it. Just what the charger needs.
Is there a limit switch in the power supply? or is it just the battery that has the smarts.. I will check, but I bet its the battery that has the smarts. I bet the power supply only regulates on the high end.
Why would I want to take it out?? I solved the issue..The charger plug has a voltage cutoff switch in it. If you want to bypass it, take it out, but I wouldn't recommend it. It's easier to regulate down than up.
You know it could also be that they don't want to drain the car battery accidentally and designed it to only take power when the car is running.
The charger plug has a voltage cutoff switch in it. If you want to bypass it, take it out, but I wouldn't recommend it. It's easier to regulate down than up.
I got that information based on the fact someone took their plug apart and there was a simple voltage switch circuit inside. @Robbyg and I being Electrical Engineers analyzed it and came to that conclusion.Actually it doesn't have a "switch", I just checked it. If you feed the power supply 10 volts it will output 10 volts, if you feed it 13 volts it will output 13 volts, if you feed it 15 volts, it will output 13 volts. It only regulates the high side.
So as I suggested the battery is doing all the work protecting its self.
Where ever you got the information about this switch, you might want to correct them..
I would hardly call this "solved"... I bought the car charger to be able to charge batteries on my bike, I don't really see myself carrying another brick twice the size and weight just to be able to use the charger with the engine off..
Justin I know we analyzed the circuit several months ago. My memory is not as good as Cyberpowers. I have worked on a lot of circuit designs since then and have forgotten what we found. Maybe somebody who remembers the post can link it.
Many Amateur Radio operators use DC-DC converters for their radios because they also have issues if the voltage drops. The concept works fine if you have dual car batteries but for the 99% of us with a single battery we can easily come back to the car and find the cars battery level at 8V and be stranded at a remote location.
I am going run all batteries out, and the controller and set it up on my bike and look at the draw and see what happens, and I have to know anyway. Will post results. But I have charged up the drone batteries using inverters, even less efficient, and not come close to flattening the battery. But this was just one charge in 3 batteries. But the battery in my car is quite big being a diesel SUV 4x4.
Are you measuring the current at all?OK, maybe it doesnt work, or mine is broken, I tested the input and output with meters.
OK, maybe it doesnt work, or mine is broken, I tested the input and output with meters.
Little detail, 400-600 amps refers to how much it can deliver at once to cold crank it. No indication of the capacity. I personally have 665 CCA battery.You can easily charge three Mavic batteries from your car battery while its stopped with no problems at all.
Three (3) Mavic battery's at 15% flatt = roughly 3000mha or X3 9000 mha or 9amps.
The average car battery, Small is 400amp, large 600amp.
So even after an hour charging 3 Mavic batterys 9 to 10 amps from 400 amp battery isn't going to flatten it. And a five minute idle with a good alternator will replace that back into car battery.
Now the DJI car charger seems to need a full 13.8 volts to provide the battery circuit an even current to charge the cells.
The problem is the car battery is an lead acid and at peak charge per cell of 2.3 is 13.8 but once that float discharge is removed the nominal voltage per cell is 2.1 or 12.6 volts.
And 12.6 is not enough to hold open the input gate on the Mavic car charger.
So you have to use a Buck Converter which takes a lower voltage of between 8 to 12v and supplies a steady output of 13.8 volts. They come in flavors of 5,8,10or15 amp so you would need at least 10 amp minimum for 3 batteries at once.
Or you could go the 12v to 240v inverter route and use your home charger plugged into the inverter.
A little more inefficient but still a cheap fix as you already have home charger and a 12v to 240v 300w can or gigarette plug inverter is only $15 to $20.