Power Inverters?

Hi,

My recommendation to you is not to use an inverter. Get a proper car power supply and use that. My reasoning is as follows:
  • It is very inefficient and uses more energy to use an inverter. You are stepping the voltage up from 5 volts to 100 in the inverter and then back down to 17.5 in the charger.
  • You will need an inverter that can support a substantial draw. The high capacity DJI charger will probably end up drawing around 90 watts due to the conversion inefficiencies.
  • Most importantly, the DJI charger is a switching power supply. That means you will need nice clean sine wave current. The cheapest inverters give you a square wave and that won't work at all. A somewhat better choice would be the Modified Sine Wave inverters and even though those will probably work without issue, there is a slight chance of it causing damage to your equipment. You would want a Pure Sine Wave inverter to do it right. So why go through the expense and carry around the bulk of a 100w Pure Sine Wave inverter when you can just get a straight car charger?
 
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Makes sense - I used to build elevators so this is right up my ally,
I have a dell power pack 18000mAh - 65W seems to charge the controller - In a pinch I wear a back pack with cable running to the controller.
Thank you
 
I use a 400w power inverter. You can only draw 150w from the car lighter, if you want more, you have to connect it directly to the battery.
 
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Any suggestions on size/Model for P4P+ controller/battery?
Thank you
I use this one 600w ,,direct to battery (visible wires for car cam) this works good for me,I only charge while driving as to not kill me car battery,boils the jug,runs tv for my viewing my drone in flight,32".good investment
20181221_075817.jpg
 
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Hi,

My recommendation to you is not to use an inverter. Get a proper car power supply and use that. My reasoning is as follows:
  • It is very inefficient and uses more energy to use an inverter. You are stepping the voltage up from 5 volts to 100 in the inverter and then back down to 17.5 in the charger.
  • You will need an inverter that can support a substantial draw. The high capacity DJI charger will probably end up drawing around 90 watts due to the conversion inefficiencies.
  • Most importantly, the DJI charger is a switching power supply. That means you will need nice clean sine wave current. The cheapest inverters give you a square wave and that won't work at all. A somewhat better choice would be the Modified Sine Wave inverters and even though those will probably work without issue, there is a slight chance of it causing damage to your equipment. You would want a Pure Sine Wave inverter to do it right. So why go through the expense and carry around the bulk of a 100w Pure Sine Wave inverter when you can just get a straight car charger?
Don’t underestimate the efficiencies typically realised by switch mode inverters, high 90’s (%) are common.

Not sure where you are getting 5v from, almost all vehicles are 12V (around 14V regulated when charging). As to power consumption the 100w DJI chargers will draw more than that (due to conversion losses). As to the claim of switch mode power supplies being intolerant to modified square wave input this is a misconception. The reality is linear power supplies are more problematic- simply because the DC components of the square wave cause transformer core saturation. This is not an issue for switch mode supplies as the supply is rectified to DC at the input. The only real vulnerable components are the smoothing caps imediatly following the input rectifier which might be subject to peak voltages exceeding their rating. Many have used non sine wave inverters and DJI chargers without issue so it seems this isn’t a problem.

Having looked at a large number of inverter outputs with an oscilloscope I have never seen one that is a pure square wave, even the cheapies were a modified square wave with crudely rounded edges from simple filters.

What you might have missed here is that inverters tend to be a great option as in almost all cases they get more use than running the DJI charger. More often than not you will have other equipment also.

If you only needed to charge DJI batteries the ciggie socket charger obviously is the most convenient solution.
 
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Don’t underestimate the efficiencies typically realised by switch mode inverters, high 90’s (%) are common.

Not sure where you are getting 5v from, almost all vehicles are 12V (around 14V regulated when charging). As to power consumption the 100w DJI chargers will draw more than that (due to conversion losses). As to the claim of switch mode power supplies being intolerant to modified square wave input this is a misconception. The reality is linear power supplies are more problematic- simply because the DC components of the square wave cause transformer core saturation. This is not an issue for switch mode supplies as the supply is rectified to DC at the input. The only real vulnerable components are the smoothing caps imediatly following the input rectifier which might be subject to peak voltages exceeding their rating. Many have used non sine wave inverters and DJI chargers without issue so it seems this isn’t a problem.

Having looked at a large number of inverter outputs with an oscilloscope I have never seen one that is a pure square wave, even the cheapies were a modified square wave with crudely rounded edges from simple filters.

What you might have missed here is that inverters tend to be a great option as in almost all cases they get more use than running the DJI charger. More often than not you will have other equipment also.

If you only needed to charge DJI batteries the ciggie socket charger obviously is the most convenient solution.

My apologies. I had USB on the brain I guess and was thinking 5 volts. Yes automobiles give you 12 volts.

For me I have not found the need for an inverter in the car but of course there are so many uses for them. The dedicated car charger still does the trick.
 
My apologies. I had USB on the brain I guess and was thinking 5 volts. Yes automobiles give you 12 volts.

For me I have not found the need for an inverter in the car but of course there are so many uses for them. The dedicated car charger still does the trick.
The DJI car chargers work very well. I got one in a fly more kit and use it all the time even though I have a big pure sine wave inverter and dedicated LiFePO4 battery pack in my off road vehicle. If the only thing you need power for is to charge your drone batteries it is easily the best solution- no question. It’s not true to say modified square wave inverters aren’t up to the task thoug.
 
I bought a 2,000 last night since Fedex claims they delivered my DJI package that’s had car charger/propellers and Misc supplies.
I went to my security tapes that show Fedex was never at my residence. I called FedEx they say your package was delivered. I went down to the office with security video in hand once again I asked where’s the truck at 3:48pm???
All I heard was Crickets.. now I’m told to contact DJI so they can file a claim...
 
I ordered one see my above post had to get something last Minute- Fedex dropped the ball on this one - Should have one soon tough with holidays..
 
Could be worse. You could've gotten a DOA unit and end up in dissapointment. Talking from experience.
 
I agree! wish they lost it - Fedex says it was delivered I was home all day it never came. I contacted DJI I told them it never was delivered and guess what they said ? " Fedex shows it delivered ... Like a dog chasing his tail ...
 
I agree! wish they lost it - Fedex says it was delivered I was home all day it never came. I contacted DJI I told them it never was delivered and guess what they said ? " Fedex shows it delivered ... Like a dog chasing his tail ...

Sorry to hear that. My advice is to document all your conversations, with date, time, etc and file a claim with your credit/debit card.
 
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I'm confused. You said that your security footage shows that FEDEX never arrived. If that is so, then the package never made it to your porch. FEDEX probably dropped it at the wrong house and the guy kept the package. What does the tracking history show when you look it up on FEDEX's webpage? I paid for a package with signature required from UPS. Got it last night, but the driver did not get anyone's signature. Here is what the webpage shows. I got my package, but I plan on letting hell loose for this mishap. What if it gotten stolen? Who would have reimbursed me? Heck no!
Screenshot_20181221-174836_Chrome.jpg
 

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