Charging P4P batteries with 12v-240v invertor

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G'day all, I hope this question hasn't been done to death!

I have been asked to run a mapping process over a mine site quarry that is approx. 20ha or 50acres.
I will be using my Phantom P4P v2 and running the Pix4D mapping app to capture the job.

I have 2 batteries and am pretty sure I can get finished with the 2 batteries, but if I need to recharge what is the general consensus of the group with using a 12v to 240v invertor from my vehicle to the standard 240v Phantom battery wall charger?

Also, if it is OK, then is there any difference or benefit to the invertor being a "pure sinewave" or not? -- The pure sinewave invertors are generally 2-3 time the price of the non versions)

There is no access to electricity on this site (or within a 30km area either!)

Thanks and I look forward to your help
 
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Regarding pure sinewave question. The actual charging current is DC. Inverter quality has increased greatly in the past few years and so have charging circuits... i.e. most chargers don't care if the incoming is 110v 60Hz or 240V 50Hz or a somewhat nasty waveform. I think you would be okay. Hope this helps.
 
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rather than spend the money on a pure converter, why not just buy a third battery? It will always be useful, whereas the inverter will only be useful in another rare instance, plus the time to recharge the first battery will be way long, and its not recommended to recharge the battery right away when hot anyway
 
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Pure sinewave, isn't necessary. I had a small 300 w that worked fine for charging my batteries from my car. I'd take pictures in one area and move on to the next, while the battery was charging. Batteries are expensive. Lol.
I bought a used p4 later and it came with a DJI car charger. It still takes a while to charge a battery.
 
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I think your math (on the mapping mission is off), 50 acres on 2 batteries????. At what altitude will you be flying? What speed? If you are doing a detailed orthomosaic 2d or 3d map, you would be flying at around 150-200 feet AGL at no more than 10-12 MPH for the clearest pictures. Ideal altitude would be 160 feet AGL and a speed of 8 MPH. 50 acres would take around 4-6 batteries with a RTH at 30%
 
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I think your math (on the mapping mission is off), 50 acres on 2 batteries????. At what altitude will you be flying? What speed? If you are doing a detailed orthomosaic 2d or 3d map, you would be flying at around 150-200 feet AGL at no more than 10-12 MPH for the clearest pictures. Ideal altitude would be 160 feet AGL and a speed of 8 MPH. 50 acres would take around 4-6 batteries with a RTH at 30%
Thanks recoveryone,
My query was not around the maths of the job but the fact I was wanting to understand the groups accumulated knowledge of charging batteries by way of 12v inverters. As I stated I will be nowhere an electrical outlet to charge as normal, hence the reason for asking the question in the first place.

As you can see via the calculations under, I think I am within the parameters of 2 batteries to complete the job but due to the fact I have no ability to charge via 240v powerpack, and that I already have a 12v / 500w invertor (which I have never used in this scenario) I was looking for advice on the ability and possible negative consequences of using such a 12v device as i am not an electrician or electronics wizz.

FYI, using the Pix4D capture app flying a 20ha single grid pattern on 3 differing altitudes (AGL) then the following is the assumption flying a 450x450mt site.
# 55mt AGL delivering 1.5cm GSD = flight time 22 mins
# 73mt AGL delivering 2cm GSD = flight time 16mins
# 90mt AGL, delivering 2.45cm GSD = flight time 12mins
This doesn't take into account time required for ascending or descending to planned altitude and distance needed to travel to the start point which generally will extend these numbers up to 5mins.
 
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Thanks everyone for your reply - It is much appreciated.
I failed to mention that I already have a (non pure sinewave) 12v / 500w inverter but have never married it to the DJI P4P 240v charger before and was wanting to know that I wouldn't destroy either the DJI charger or the inverter or both....
I think I will go ahead and give it a go anyway and this may also help in ensuring I have charged batteries as I travel from site to site in the car. (with the understanding the rate of charge will be longer)
 
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Have done exactly what you wish to do - in outback WA - with good effect and on a much smaller inverter than you mentioned. I did find that it could not draw enough power through the cig. lighter socket and I had to hook it up directly to the vehicle battery via alligator clips. No worries and no damage to anything. I was well equipped with plenty of solar panels tho and would add that you wouldn't want to strand yourself by flattening the car battery during the AC recharging process!
 
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Have done exactly what you wish to do - in outback WA - with good effect and on a much smaller inverter than you mentioned. I did find that it could not draw enough power through the cig. lighter socket and I had to hook it up directly to the vehicle battery via alligator clips. No worries and no damage to anything. I was well equipped with plenty of solar panels tho and would add that you wouldn't want to strand yourself by flattening the car battery during the AC recharging process!
Thanks mate, that's great - I have alligator clips and extra wire and I will make an extension to the inverter. I feel better having a crack at this now.. This is a good forum getting others experiences and advice. Thanks again.
 
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Thanks mate, that's great - I have alligator clips and extra wire and I will make an extension to the inverter. I feel better having a crack at this now.. This is a good forum getting others experiences and advice. Thanks again.
No worries. You could always avoid the need for "extra wire" by just placing both the AC battery, charger and inverter somewhere safe under the hood - slightly ajar - unless it was flooding type rainfall. Worked for me ?
 
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No worries. You could always avoid the need for "extra wire" by just placing both the AC battery, charger and inverter somewhere safe under the hood - slightly ajar - unless it was flooding type rainfall. Worked for me ?
Yours is a good idea - i will run 6 gauge wire from the battery through the firewall into the back seat and have an Anderson type plug to connect/disconnect to the inverter.
Should be simple and clean.
 
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Thanks recoveryone,
My query was not around the maths of the job but the fact I was wanting to understand the groups accumulated knowledge of charging batteries by way of 12v inverters. As I stated I will be nowhere an electrical outlet to charge as normal, hence the reason for asking the question in the first place.

As you can see via the calculations under, I think I am within the parameters of 2 batteries to complete the job but due to the fact I have no ability to charge via 240v powerpack, and that I already have a 12v / 500w invertor (which I have never used in this scenario) I was looking for advice on the ability and possible negative consequences of using such a 12v device as i am not an electrician or electronics wizz.

FYI, using the Pix4D capture app flying a 20ha single grid pattern on 3 differing altitudes (AGL) then the following is the assumption flying a 450x450mt site.
# 55mt AGL delivering 1.5cm GSD = flight time 22 mins
# 73mt AGL delivering 2cm GSD = flight time 16mins
# 90mt AGL, delivering 2.45cm GSD = flight time 12mins
This doesn't take into account time required for ascending or descending to planned altitude and distance needed to travel to the start point which generally will extend these numbers up to 5mins.
Also as said above, you need to let a battery cool down for a while before charging. I do think in practical application you’re going to want at least 1 more battery.
Doesn’t mean you shouldn’t try, but it may include some wait time if your 2 batteries aren’t enough to cover.
 
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Also as said above, you need to let a battery cool down for a while before charging. I do think in practical application you’re going to want at least 1 more battery.
Doesn’t mean you shouldn’t try, but it may include some wait time if your 2 batteries aren’t enough to cover.
Thanks mate, I will let it cool down. I will also look to get another battery or 2 anyway - by the way, do you have any massive concerns with non DJI batteries?
 
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Regarding pure sinewave question. The actual charging current is DC. Inverter quality has increased greatly in the past few years and so have charging circuits... i.e. most chargers don't care if the incoming is 110v 60Hz or 240V 50Hz or a somewhat nasty waveform. I think you would be okay. Hope this helps.
I'm no electronic genius either but I do have a knack for having the ability to read warnings. When I was looking for an inverter, I read that the crappy sinewave of non-pure inverters can seriously damage sensitive electronics. That's all I needed to hear to convince me to buy a pure sinewave device. Found a good, new 12V 5000W one for about $100. Works fantastic.
 
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I'm no electronic genius either but I do have a knack for having the ability to read warnings. When I was looking for an inverter, I read that the crappy sinewave of non-pure inverters can seriously damage sensitive electronics. That's all I needed to hear to convince me to buy a pure sinewave device. Found a good, new 12V 5000W one for about $100. Works fantastic.
Bargain!! Got a link, please? Cheers
 

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