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  1. #21
    Holly's Avatar
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    Ok, so I spoke to lots of places today about all this, and Kayell in Sydney said that there's basically no point trying to rewire the US version unit
    because it's just built that way and wouldn't have the capacity to be changed. (?) Not sure what I think about that. They agreed that a transformer
    would work, but then directed me to somewhere like Tandy or Dick Smith's (which are commercial retail places for things more like Playstation
    and household electronics). So I got the feeling they weren't particularly expert in their represented brand of Elinchrom :/

    Then I spoke to some electric equipment wholesale guys, all agreed that there should be no problem using the 1500W transformer to
    power the units but that few places where I live stock that size one and I'd be best off looking on the net or interstate in Aus to buy one.
    But I am still hung up on the finer details of making sure I don't kill the flash head, so now I have looked at a few websites who
    specialise in stepdowns and all kinds of transformers, and they keep coming up with this list of questions (cut and pasted from one site here):

    1. What is the total watts used by appliances to be connected to the Transformer?

    Select from our Stepdowns range below based on how many watts your device uses*.

    E.g: Playstation 3 uses 380 Watts so you need 500 watt stepdown transformer.

    2. Does your appliance have a motor ?

    If a motor is included then you should select a stepdown rating at least 25% higher than your motor as a buffer. Motors have higher power use on the stepdowns and startup currents which need to be allowed for. Most motors have a rating plate on them with their Power and Amperage rating.

    3. Does your appliance have a mechanical timing device? If so, how critical is this timing device?

    If a timing device is included the speed of the device may change due to the frequency change, 60Hz to 50Hz (eg old clocks, motors / fans)
    4. Do you know the Amps of your device? - is so you can calculate the watts required:

    Calculated as Watts = Amps x 110 Volts (eg 5 A x 110 V = 500 watts)
    5. Do you wish to use multiple appliances from one stepdown?

    Check total watts of all devices this must be less than the VA rating of the stepdown & get a US Powerboard

    So does my type of flash head have a motor/timing device/heating element/pump/compressor ? I'll need to know this
    if I'm talking to anyone I'm purchasing from, so I can get the right one. I'm just not sure if what's inside the guts of the
    Style rx 600 could technically be called a motor, or if it would have any extra wattage needs that we haven't already
    thought of?

    Snederhiser, you're right, it would be a palaver trying to get new lamps/cords/electrician costs out the way before I could
    use the flash, and it just seems like the transformer can do all of that in less steps.

  2. #22
    Steve Smith's Avatar
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    Quote Originally Posted by Holly View Post
    But I am still hung up on the finer details of making sure I don't kill the flash head, so now I have looked at a few
    If you connect it to a transformer with the correct voltage output there is no reason why you should damage it. It would be the same as taking it to America and plugging it into a wall socket.

    Quote Originally Posted by Holly View Post
    it would be a palaver trying to get new lamps/cords/electrician costs out the way before I could
    use the flash, and it just seems like the transformer can do all of that in less steps.
    It can (fewer, not less - free pedantic English lesson!).


    Steve.

  3. #23
    polyglot's Avatar
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    Like people say, get the transformer. I would suggest though that you buy them (the identical device!) from eBay though for pricing reasons. I have bought two separate 2000W units (one to run a US-model amplifier/receiver and one to run a KitchenAid) and they're about $65 each; see item 270767008656 (I have bought from this seller and recommend them).

    In terms of answers to your latest questions, they are:
    1) about 1000W* including the modeling lamp
    2) no, nor does it have a poor power-factor or high inrush-current, which is what they're really asking
    3) no
    4) irrelevant, since we know the approx total power
    5) presumably yes

    The power ratings on the transformers are largely thermally limited and aimed for continuous use, while the flashes draw power for only about 1.5s each time you fire them. Therefore you can comfortably run two of the flashes from a single 2000W transformer (it will hum a bit during recycling but will work fine). The transformer would be less-stressed if you bought the 3000W version** but I don't think that is necessary. The transformers have two sockets on the front so you won't need a powerboard; just plug the two flashes in using their original US cords.

    If connecting two flashes to the 2000W transformer causes its breaker to pop, you could buy a second 2000W transformer (one for each flash). This is highly unlikely with your higher-quality flashes though, so don't worry yet.


    While there is a 240V version of this flash, there will be big differences in how the recycling circuit is setup so it is generally not economic to modify the 110V to work with 240V. Using a transformer is the best option.


    * it's a 600J flash with 1.5s recharge (400W output power into the capacitors), but the charging circuit is often only about 70% efficient. Recycling the flash will therefore pull about 500-600W, plus the modelling light is 150W on the 110V version, though there looks to be a 250W option. The expected power consumption is therefore about 750W, so 1000W is a fairly safe/conservative estimate.

    ** eBay 140670722876 is clearly from the same chinese factory, just larger.
    Last edited by polyglot; 04-17-2012 at 03:02 AM. Click to view previous post history.

  4. #24
    polyglot's Avatar
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    Quote Originally Posted by Steve Smith View Post
    If you connect it to a transformer with the correct voltage output there is no reason why you should damage it. It would be the same as taking it to America and plugging it into a wall socket.
    I don't wish to be disagreeable but that's not quite true. Most stepdown transformers are autotransformers (single winding with a centre-tap). If you overload them to failure, one end of the winding will go open-circuit, which will result in either no output voltage, or delivery of the full input voltage to the output, which means the magic smoke gets let out. Using grossly under-rated stepdown transformers can be quite hazardous to the load equipment.

    It's not too bad for 240V->115V where the voltage ratio is about 2:1 and the current through each end of the winding is about equal (you have a 50:50 chance of catastrophic:harmless failure modes). For greater voltage ratios, the current ratio is no longer 1:1 and the catastrophic becomes the only likely failure mode. In those cases, isolated transformers are generally the only good option.

  5. #25
    Steve Smith's Avatar
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    Quote Originally Posted by polyglot View Post
    I don't wish to be disagreeable but that's not quite true. Most stepdown transformers are autotransformers (single winding with a centre-tap). If you overload them to failure, one end of the winding will go open-circuit, which will result in either no output voltage, or delivery of the full input voltage to the output, which means the magic smoke gets let out.
    Whilst this is true, I would hope that the transformer has a fuse in place to maintain the integrity of the magic smoke containment devices. And with excessive load, the winding from the unit being powered to the live input will be the one most likely to fail so this will cut the power to the device. The winding in parallel with the output is less likely to fail under excessive load as the voltage across it will reduce as the load increases.

    I do agree with you that an isolated transformer is the best option and personally, I think that should be the only option available but as we know, these days things are built down to a price rather than up to a quality so the cost effectiveness of an auto-transformer wins.


    I think the OP was worried about the general idea of plugging into a transformer. With the transformer suggested, there should be no problem.


    Steve.

  6. #26
    polyglot's Avatar
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    Quote Originally Posted by Steve Smith View Post
    Whilst this is true, I would hope that the transformer has a fuse in place to maintain the integrity of the magic smoke containment devices. And with excessive load, the winding from the unit being powered to the live input will be the one most likely to fail so this will cut the power to the device. The winding in parallel with the output is less likely to fail under excessive load as the voltage across it will reduce as the load increases.

    I think the OP was worried about the general idea of plugging into a transformer. With the transformer suggested, there should be no problem.

    Steve.
    As far as the OP goes, there is indeed no need to worry as long as the transformer is not underrated. I have two of these things in my house, they're $65 autotransformers but hugely overrated for their loads and will basically never fail. You can spend the extra for an isolated transformer as linked on the first page but the additional cost is so huge (as much as a new flash!) as to be pointless.

    If the voltage ratio is greater than 2:1 (e.g. 240V -> 60V), then there is more current through the parallel winding (N-1 times the input current for a voltage ratio of N) than the series winding, so it's the parallel winding that will fail. If we're talking about a 2:1 transformer that's overloaded, there's still a 50:50 current ratio through the windings and a 50:50 chance of the catastrophic failure. Best idea is to not stress the transformers, which is why buying any old $20 100W autotransformer would be a really bad idea - you run a 50% chance of destroying your flash by plugging it into that.

    Fuses prevent fires, not damage; the fuse will only blow when the current gets too high, not the voltage. Especially once you consider fuse reaction times, the load device will certainly be destroyed (though not necessarily irreparably) before the fuse pops. The fuse is depending on fault-current through the load to blow so by definition it cannot save the load from damage. While it is possible to build an over-voltage protection circuit, they're not included in these cheap transformers.
    Last edited by polyglot; 04-17-2012 at 03:37 AM. Click to view previous post history.

  7. #27
    mr rusty's Avatar
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    magic smoke containment devices
    Ha! someone else who knows the secret knowledge that everything electrical is actually operated by smoke, not electrons like they teach in skool. Once the smoke escapes the device can't work.

    The expected power consumption is therefore about 750W, so 1000W is a fairly safe/conservative estimate.
    Totally agree. The manual actually says "maximum connected load A/VA = 6.3/1500" which as I said before will have a safety margin built in. As the 1500W transformers I found links to were continuously rated at 1000W and only 1 hour at 1500W, if it was me that's what I would go for, for the little extra comfort of knowing I was well within spec no matter how hard I pushed, but totally agree that a single 2000W unit with 2 outlets will 99.9% be OK most of the time.

    I would suggest though that you buy them (the identical device!) from eBay though for pricing reasons
    I didn't do enough research!! Holly - this is definitely the way to go!

  8. #28
    Holly's Avatar
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    Oh my god, I'm confused now!

    Magic smoke?! What? You're losin me guys, bear in mind I'm quite right-brained and number-dyslexic at the best of times.
    So Polyglot, the way you added it up to 1000W, you're saying that each 600W flash head will really equal only 1000W and so I could
    get away with plugging the two of them into the one 2000W transformer?

    When you say 'causes its breaker to pop' if connecting both flashes at once, does that mean I've killed that transformer and need to
    get it fixed by someone? I don't know the lingo too well, sorry.

    I couldn't find that item number on ebay, can you give me a link pls? I kind of want to buy from an actual shop in Aus, knowing my
    luck and ability to screw even the simplest things up, if something does go wrong with the transformer/s I'll need the peace of mind
    that I can call a Sydney or Melbs number and not have to deal with o/s language barriers, etc. Thinking it will just be less hassley.
    (With *fewer* hassles, Steve! lol)

  9. #29
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    Hi Holly

    Sorry, no intent to confuse! Just go and buy either 1 x 2000W step-down from ebay from the link polyglot gave. It will be good enough. Alternatively you could buy 2 x 1000W units. These will be just powerful enough for the job. If you are feeling slightly richer and want a little more security get 1 x 3000W or 2 x 1500W. These will run with slightly less stress. Honestly, they WILL work. You don't need to spend extra by going to a shop.

    Ignore the comments about magic smoke. Its a secret known only to those who tinker with things electrical.

  10. #30
    Steve Smith's Avatar
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    Quote Originally Posted by mr rusty View Post
    Ignore the comments about magic smoke. Its a secret known only to those who tinker with things electrical.
    And pay no attention to that man behind the curtain.


    Steve.

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