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Car charging using 300W 110V AC modified sine wave inverter?

Discussion in 'Inspire 1 Discussion' started by Jesse Rockwell, Sep 24, 2015.

  1. Jesse Rockwell

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    Hello. First post here. My Inspire arrives tomorrow, and I have needed a car charger for my photography equipment for a long time, so I went ahead and ordered this

    http://www.amazon.com/gp/product/B004MDXS0U?psc=1&redirect=true&ref_=od_aui_detailpages00

    I know it will work for a laptop and camera batteries, but not so sure about my Tb47 and Tb48 batteries. Can anyone confirm whether or n ot this will work. I am going into the desert for a week, and would like to have a reliable charging solution!

    Thanks!
     
  2. The Editor

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    I have moved this thread to the correct section.
    Please do a search on the forum as this has been covered many times before.
    Try searching on "Charging with an inverter" or similar and you will see a lot of results.

    Basically, these types of inverters are not advisable for 'delicate' equipmemt as they provide a poor sine wave output and can damage some devices. You need a pure sine wave inverter for your purpose.
     
  3. SultanGris

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    I somewhat disagree with this and havent found any definitive documentation saying modified sine wave inverters will cause any problems whatsoever with charging a battery yet. Ive seen lots of people say you need pure sine wave for charging them with zero links to any reliable source information. Lots of people say lots of things on the internet that arent reliable and due to no one researching before spreading info they heard from their buddies girlfriends brothers cousins guy he met in a bar one time I dont believe things without reliable sources. That said if you can afford a pure sine wave inverter it definitely wouldnt be a bad thing to get instead of a modified sine wave inverter, but i couldnt say for certain its required. I use the stock inverter in both my 2013 f350 and my 2007 keystone cougar 5th wheel RV to charge my batteries with no problems. I cannot find any info on what type of inverter either of them have so i might be wrong, but since the pure sine wave inverters can cost significantly more i assume they are both modified. At any rate near as I can tell from what ive read about them if they were to damage anything it would more likely be the charger and not the battery or they simply wouldnt even work at all.
     
  4. The Editor

    The Editor Moderator
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    It's not charging batteries from a modified sine wave inverter that's the problem - it is running switched mode PSU's from rough waveform supplies.
    The theory behind SMPSU's is really outside the scope of this forum but basically they work by 'chopping up' the sine wave of the mains supply that is being fed into them. They operate on the basis that a regular frequency and amplitude is being fed to them and they sample that frequency to produce their (lower voltage) output.
    If they are fed with irregular/dirty mains supply then they CAN produce inaccurate/fluctuating outputs. Couple this with transient spikes and you have a situation which is not great for more delicate electronics.
     
  5. SultanGris

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    while this is true enough from what ive read there is not a problem with most PSUs using modified sine wave inverters, certain ones will not work with them but most do just fine. Things like some digital clocks, monitors, florescent lights, laser printers, photocopiers, and some laptops wont work reliably on modified sine wave inverters and some will. All i know for sure is that the batteries charge just fine with no problems on whatever types i have, i wish i could find definitive information on which ones they are as im only assuming they are not pure wave inverters but so far ive not been able to find that information so I could be incorrect here and i apologize if i am but to date ive seen no proof either way so i remain skeptical.
     
  6. Ezookiel

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    I ran my charger off a cheap Waeco "can" inverter just fine.
    I've also run it off the inverter built into the ArkPak mobile battery box just fine.
    HELL ... In one instance with my P2 batteries I ran two wires directly from the car battery to the terminals on the P2 battery (a five day trip miles from civilisation and left my charger at home) and that also worked just fine because the smart charger is built into the battery, it just needed power. (You do need to turn the battery on to make charging start if you do it this way, and it never turns off, so sometime after the 4 LEDs stop flashing and go solid, you need to unplug it yourself)
    I can't say whether using cheaper inverters is good or bad, neither in the short or long term, but I can say I've used cheaper inverters successfully with both P2 and I1 batteries (TB47 and TB48s) without problems so far. I intend to get a 200+w one for my car now so I can use the 180w fast charger in future.


    Sent from my iPad using Tapatalk
     
  7. SultanGris

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    after more research ive discovered the stock F350 power inverter is very likely modified wave. The owners manual lists similar devices that may not operate correctly with modified wave inverters as an online inverter FAQ i found does. The online FAQ also states that most battery chargers work just fine with modified wave inverters, only a select few will have an issue. Unsure if there any way to tell or if they would not work, be damaged instantly, or take multiple uses to show any signs of a problem but all signs suggest it would cause instant damage or simply not work if there was an issue and as ive used mine to charge them multiple times i think its safe to say there is no problem with doing so on a modified wave inverter.
     
  8. The Editor

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    But do not forget the DJI brick that plugs into the Inspire batteries is not a battery charger. It is a switched mode PSU.
    People I am sure will make up their own minds and people will ignore advice and follow their own path.
    Personally I choose not to use inverters because I understand electronics (I was trained in electronic engineering) and I understand the theory behind how the inverters work and the stress that can be put on the connected electronics.
    Everyone is free to connect whatever they like to whatever they want to. As long as you are comfortable in your own mind doing what you are doing, then go ahead.
    I only offer my advice from experience and background on these forums.
    Nobody is forced to follow it.
     
  9. SultanGris

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    Fair enough, im no electrical engineer, Im not trying to offend you or say you dont know what youre talking about or anything but ive been reading about it for a while and Im not really seeing any info anywhere that says using an smps on a modified wave inverter is harmful, if you could link any such sources about that you know of i would greatly appreciate it. Im just trying to understand if it really is bad, why it would would be bad, when any problems signs would be noticeable and so on since ive been using it to charge mine for a while now with no problems.

    Does this mean my batteries might have problems down the road? or do these problems happen rather instantly if they are going to happen? Some articles ive read suggest if there is any problem it would damage the charger unit and not the battery, do you think thats true or not?

    Do you think that the guy who answered this question who says using smps with modified wave inverters mostly doesnt matter is incorrect then? I dont generally put much stock in this types of info without any listed credible source, but no one said hes wrong and other credible articles ive read seem to share his opinion. How does an inverter affect the computer?

    Or what about the info here, which seems to suggest that smps function on quality modified wave inverters? Power inverter - Wikipedia, the free encyclopedia

    Any info you can provide is greatly appreciated, however if you have better things to do than try and answer my 400 stupid questions to explain it to me thats cool, I totally understand and wont be offended if you dont. From your perspective it might be like trying to teach a first grader calculus or something, lol! Im just trying to learn more about it and fully understand the problems and possible damage that might occur as ive not noticed any issues yet and the information ive been able to locate so far is inconclusive.
     
  10. The Editor

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    LOL - no worries, I understand an inquisitive mind. :)
    Basically, in the instance we are talking about here which is using a modified sine wave inverter to feed the DJI switched mode power supply which in turn feeds DC out to the intelligent smart battery we just do not know how well both the power supply and the charging circuit has been designed/protected.
    It is entirely possible that using a MSW inverter could stress the electronics in the PSU or charging circuit or both.
    However, you are unlikely to see the effect in real time. The devices will function and do their job but what you may experience is a shorter time to failure (MTBF) resulting from the unseen harmonics and resultant stress.
    I am just Captain Cautious and if I can avoid or mitigate potential risk, I will. Yup, I'm boring. :p
     
  11. SultanGris

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    I definitely see your logic there, however the reason i care so much about it is because i have two modified wave inverters i use to charge mine. One in my f350, and one in my 5th wheel RV. If i didnt have any I would probably just go buy a couple pure wave ones and forget about it but since i already have two id really rather not have to replace them both if its not necessary if you know what i mean.

    Considering they are smart batteries and are supposed to protect themselves from overcharging i would think/hope they wouldnt be damaged if there was such an issue. If the smps charger device was to only last 2-5 years due to using modified wave inverters instead of 20 or whatever if not used with them i could live with that, though i really dont want to be possibly destroying 200 batteries very often so my quest for knowledge continues, ha!