d0462

Hi all, I hope you can help me out. I bought a Dahua SD59230T-HN from Aliexpress ("hey that's an impressive functionnalities/cost ratio!") and started working on integrating it in my isolated system managed by a Raspberry Pi. Anyway, it worked well during a few trials with a lab power supply (supplying constant 12VDC), but after a few tries hooked up to a 12V battery system (the camera worked nicely on 2 or 3 different trial days), the camera won't power up anymore since the last time I shut it down. A few points of context so that you better understand the situation: 1. The first thing I got wrong was to go too fast in buying that model, I realized that that it must apparently be powered in 24V AC. So from the beginning I acquired a 12VDC to 24VAC from PowerStream and hooked everything up. Power flow through that converter is opened/closed by a MOSFET transistor as I need to save batteries as much as I can and therefore I would like to power the camera only a few minutes a day (this switching on/off has been working perfectly fine). Now, although the converter switches on nicely, a voltmeter shows that I have 28.5V at the output side. So I suspect an overvoltage situation, but I have no other mean of providing 24VAC as a test and thus don't know if anything was damaged or if I can "reset" the camera for that kind of situation. The guy from PowerStream told me that "indeed, these tend to output a higher voltage than the spec when not loaded, but once power is drawn voltage stays within specs (i.e. 24v +/- 10%)". Which is maybe why once the camera was on I had no problem at least until the next shut down. 2. That system is as stated above powered by a 12V battery charged by solar panels. As a consequence, input voltage at the input side of the converter can vary roughly from 12 ich to 14 ich. I should have place a voltage regulator from the beginning to at least cope with that source of variation but did not. 3. I think this happens once before: I had a time when the camera didn't start right away, but did after I tried to connect the power supply which was shipped with the camera (converter from 220V mains). And the camera woke up after a few minutes... and it worked again when hooked up after that on my 12V to 24V converter... 4. The issue this time is that nothing happens even if I connect the camera to the power supply shipped with the camera. I still read a voltage higher than it (maybe) should be, around 26.5V, but nothing happens ...