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RE: Pure sine wave Ac inverter - Help

  • 24-10-2014 4:25pm
    #1
    Gehad_JoyRider
    Registered Users Posts: 1,634 ✭✭✭


    Hey,

    Figured this would be the best place to come for advice and more so where to bye one, I need a 400 watt pure sine wave Ac inverter. Its not for a motor home or caravan. I figured people into Motor-homes and camper-vans would have good knowledge.

    Basically I have photography Lighting and I need to power it. I can't afford a mobile battery pack. How ever a bit of searching said a car battery and a inverter and charger could work. Judging bye you tube its possible.

    The lighting is http://www.elinchrom.com/product/D-Lite-RX-4.html if you want to get and idea of what I need to be powering. I'll be powering two lights.

    Any advice where I can get one what battery's and where to get an inverter in Ireland would be so helpful.
    Thanks


Comments

  • #2
    [Deleted User]
    Posts: 5,238 ✭✭✭[Deleted User]


    Bittova challenge to run a strobe off an inverter. Surest way to kill it imho.

    2 x 400 Ws = 800 watt inverter and you could probably do with a lot of headroom for that.

    I've had my eye on this for a while now.

    Any way you can measure the inrush of the flash? Those beasties are brutes.


  • #3
    [Deleted User]
    Posts: 5,238 ✭✭✭[Deleted User]


    1200VA (per lamp recycling) equates to 1200 Watts compensating for power factor so you might need two of the above listed units.

    30kg of lead acid should get you a run-time of about 3 hours give or take (worst case scenario 30 mins).

    Datasheet here see page 16.


  • #4
    Gehad_JoyRider
    Registered Users Posts: 1,634 ✭✭✭Gehad_JoyRider


    Sir Liamalot wrote: »
    Bittova challenge to run a strobe off an inverter. Surest way to kill it imho.

    2 x 400 Ws = 800 watt inverter and you could probably do with a lot of headroom for that.

    I've had my eye on this for a while now.

    Any way you can measure the inrush of the flash? Those beasties are brutes.

    Can you explain to me why inverter would kill the head? kinda curious, its the only option I got.. i could bye one of these but my budget is tight. But if your reason stands to logic I would re think it.

    Sir Liamalot wrote: »
    1200VA (per lamp recycling) equates to 1200 Watts compensating for power factor so you might need two of the above listed units.

    30kg of lead acid should get you a run-time of about 3 hours give or take (worst case scenario 30 mins).

    Datasheet here see page 16.

    I presume power to time would be dictated to weather Im hammering the lighting in power Ie possibly compensating to the sun?

    I did come across this video here
    https://www.youtube.com/watch?v=DWLMmhY0YW4


    Thanks for the data sheet :)


  • #5
    [Deleted User]
    Posts: 5,238 ✭✭✭[Deleted User]


    Gehad_JoyRider wrote: »
    Can you explain to me why inverter would kill the head?

    The head will kill the inverter.
    Recurrent hard starting. The electronics won't like it.
    Gehad_JoyRider wrote: »
    I did come across this video here


    Ah come to think of it yes most inverters are double rated...continuous and peak power. Usually it's double rated for peak.

    Gehad_JoyRider wrote: »
    I presume power to time would be dictated to weather Im hammering the lighting in power Ie possibly compensating to the sun?

    Yup.

    I'll have a rethink in a bit.


  • #6
    Gehad_JoyRider
    Registered Users Posts: 1,634 ✭✭✭Gehad_JoyRider


    Sir Liamalot wrote: »
    The head will kill the inverter.
    Recurrent hard starting. The electronics won't like it.




    Ah come to think of it yes most inverters are double rated...continuous and peak power. Usually it's double rated for peak.




    Yup.

    I'll have a rethink in a bit.


    so does that mean it might work? :D


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  • #7
    [Deleted User]
    Posts: 5,238 ✭✭✭[Deleted User]


    Yeah might work, can't guarantee how long for though. Or even if there's any economy in it.

    I'm guessing the heads have a "power buffer" ballast type jobbie for the flash so it's not like a traditional strobe and therefore easier on the inverter. Some of the better inverters have built-in soft starters which might be worth a look.
    I'd recommend fully testing the heads for definitive numbers on running load and inrush before spending on more kit though.

    Might take me a while to get back with a possibly workable solution, I'm in the middle of a PC reformat.


  • #8
    moodrater
    Closed Accounts Posts: 1,638 ✭✭✭moodrater


    The lighting unit has automatic voltage detection dont know if that at power on or continuous but one scenario that could cause smoke signals is if the inverter sags at power on or during operation and it switches to 110v then the inverter goes to 220v.

    Id look for advice from the manufacturer.


  • #9
    [Deleted User]
    Posts: 5,238 ✭✭✭[Deleted User]


    110v inverter or bypass the input relay.
    Neither are very desirable solutions.
    moodrater wrote: »
    Id look for advice from the manufacturer.

    Soon as you mention inverter they'll tick the warranty void box.


  • #10
    moodrater
    Closed Accounts Posts: 1,638 ✭✭✭moodrater


    Sir Liamalot wrote: »
    Soon as you mention inverter they'll tick the warranty void box.

    Yeah especially when they're in the market for selling €2500 battery packs :eek:

    Seems it doesn't need so much beef after all, modelling lamps excluded:
    http://www.barkerphotographic.ie/index.php?route=product/product&product_id=459&search=power

    https://www.youtube.com/watch?v=oFmDfyeq0y0


  • #11
    [Deleted User]
    Posts: 5,238 ✭✭✭[Deleted User]


    Gehad_JoyRider wrote: »
    i could bye one of these but my budget is tight.

    That's just an overpriced UPS. I guess they're charging you an extra €300 for the snazzy case. Here's a much better deal. 60kg's probably a bit hefty though.
    I reckon you'd be better off going down that road.
    Gehad_JoyRider wrote: »
    Hey,
    I need a 400 watt pure sine wave Ac inverter. Its not for a motor home or caravan. ...
    The lighting is http://www.elinchrom.com/product/D-Lite-RX-4.html...I'll be powering two lights.

    Where did you get this 400W figure? From the datasheet two RX4 heads will need 280W idle and 2400VA peak.
    VA explained

    In inverter territory you're into the €1.5K range.

    Now the fact of the matter is the flash charging unit will probably just take longer to charge and molest a lesser inverter until it delivers a more wholesome curve of a waveform so say it takes 3 seconds to charge instead of 1.2 then has a rest. In which case €750 might get you there and you're on borrowed time and you still need batteries and a charger.
    The inverter in the youtube link is a fairly robust 110v unit.

    Because it's an instantaneous load you might just get away with it and simply discharge all the capacitors in the inverter. Either way I can't say it's good idea.

    I think the good folks in electrical might have some further insight if you care to ask there.


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  • #12
    [Deleted User]
    Posts: 5,238 ✭✭✭[Deleted User]


    Gehad_JoyRider wrote: »
    I need a 400 watt pure sine wave Ac inverter.

    http://uk.rs-online.com/web/p/dc-ac-car-power-inverters/7646820/

    whistling.gif


  • #13
    moodrater
    Closed Accounts Posts: 1,638 ✭✭✭moodrater


    Sir Liamalot wrote: »
    http://uk.rs-online.com/web/p/dc-ac-car-power-inverters/7646820/

    whistling.gif

    What a terrible brand name, mean well. That always prefaced by something going wrong !


  • #14
    [Deleted User]
    Posts: 5,238 ✭✭✭[Deleted User]


    moodrater wrote: »
    What a terrible brand name, mean well. That always prefaced by something going wrong !

    I hear they're conversely fairly reputable, US made. Not that I have any of their products. 400W is a funny number in inverter land here's a few more;

    Mascot 600W Swiss
    Maplins 600W Re-branded Chinese
    Merlin Equipment 400W UK
    Victron 350W Europe
    Magnum 600W 110V US
    Samlex 600W 230V US
    Studer 500W Swiss

    I still reckon you'd be better off with a UPS. They're specifically designed for expensive electronics. Much superior regulation and availability.


  • #15
    [Deleted User]
    Posts: 5,238 ✭✭✭[Deleted User]


    Sterling Power UK 600W bottom of page.

    The other thing is your heads expressly advise earthing, in several places in the manual. I don't know if that's for electrical safety in which case you might get away with an RCD and an earth spike or it could be an electronic issue.

    Earth spiking inverters is a bittov a contentious issue so best ask an expert.

    It also advises not connecting more than one to the same outlet (possibly because they could trip 10A breakers it used in tandem)


  • #16
    [Deleted User]
    Posts: 5,238 ✭✭✭[Deleted User]


    Sir Liamalot wrote: »
    I'd recommend fully testing the heads for definitive numbers on running load and inrush before spending on more kit though.



    This guy's almost got the right idea but he's a bittova dope.

    He's measuring the DC side of the inverter with a cheapo AC meter from the negative cable facepalm.gif and getting wildly inaccurate readings. You just need the AC side from a wall socket to size the inverter anyways. Preferably a meter with inrush & hold or max/min would be good.

    Disregard everything after 9mins30 he's blowing smoke, utility batteries are deep cycles, he's just probably thrashed it from overdischarge and the MSW versus true sine hypothesis is oversimplified, the problem with MSW inverters is the power factor is dreadful.

    Using his numbers;

    6A x 115V = 660W recycling
    0.1A - 0.3A x 115V = 11W - 35W idle


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