Transform 110vac 60hz to 208,220vac 60hz

Discussion in 'General Electronics Chat' started by killivolt, Nov 20, 2013.

  1. killivolt

    Thread Starter Active Member

    Jan 10, 2010
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    I have someone I work with who purchase a network box that runs on 208vac, he wanted to install it on a 110vac line.

    I think it runs around 9-10amps so it wouldn't exceed a 15amp breaker.

    Anyone have experience with this?
     
    Last edited: Nov 20, 2013
  2. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Convertors don't usually convert freq.
    You can get control transformers from an Electrical dist. that will go 208-220 to 120vac.
    Max.
     
  3. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    Not sure where 50hz comes into question at all here as you state 60HZ and are in the US..

    many of the devices (like Dell Blade servers,etc..) state 208V but may accept 208-240VAC..
    As such it just requires a typical 220V US circuit..
    This can be done with 2 x 110V circuits..

    Remember something that draws 9 to 10 Amps on 208-220V can draw twice that on 110V (if the power supply supported 110V)

    We just had a "similar" problem at work where our IT guy didn't pay attention and bought a 208V server.. We simply wired a 220V circuit and voila.. Done properly.
     
  4. killivolt

    Thread Starter Active Member

    Jan 10, 2010
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    Thank you for your post.

    First off, I removed the line on 50hz. Don't think about it, I thought they might have a such an animal that would switch 50hz to 60hz 220v to 110v


    So, if I'm hearing this correctly, if he takes 2 110 lines off a normal split phase 220v with a neutral to feed the server, correct? It can't be done otherwise correct, it can only be done from separate phases.

    He just would need to know if, the other line e.g. 2 different outlets separate phases.
     
  5. MaxHeadRoom

    Expert

    Jul 18, 2013
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    In N.A. the 240v is simply 1ph transformer with a centre tap if 120v is needed, one end and the centre tap is used if 120v is required..
    If the unit is 240v the C.T. does nothing and is not needed..
    Max.
     
  6. inwo

    Well-Known Member

    Nov 7, 2013
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    Either have a 208/240 circuit wired properly or get a suitable transformer.

    You might check to make sure device is not "dual voltage".
     
  7. killivolt

    Thread Starter Active Member

    Jan 10, 2010
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    My first thoughts were "Yes" they should make a Step up Transformer that will work, I've seen some but, I wasn't sure about wether he could get a good one or one that would cook his server.

    But, as someone mentioned if drawing what ever amperage is on the device it will likely double if pulling the Voltage from a 110v circuit.

    Do you have a suggestion on a good one?
     
  8. MaxHeadRoom

    Expert

    Jul 18, 2013
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    I misread, I thought you wanted 120v.
    Why not get a common 240/120 transformer and connect it backwards.
    Max.
     
  9. David Pate

    New Member

    Oct 29, 2013
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    Why not just get an electrician to install a 220 volt outlet. In your home the stove/oven and generally the clothes dryer are on 220 volt circuits. Also most built in air conditioners. If you want to go the transformer route, then I would advise that an electrician be involved to ensure it is correctly rated and wired up correctly.

    Split phase power was mentioned above; in a home the wiring is split single phase, so both 220 & 110 are available: 220 is not split, and the 110 is split into 2 balanced circuits within the breaker panel. Again, an electrician would be able to advise how to keep a 110 system balanced.
     
  10. killivolt

    Thread Starter Active Member

    Jan 10, 2010
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    I wouldn't be able to stay above the Amperage rating if I reverse it. Correct?

    I've already told him this. But, I thought I would (Put it to the Forum) to ask if such a box solution existed or not?

    He thinks he can just go buy something and it will work. I told him it's not that easy. "He's a programmer from China, very smart, but, smart enough to outsmart himself:)"
     
  11. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    You simply install a 220V circuit.. Thats it.. Nothing more than that..
    But as clearly AC is not in either of your wheelhouses you should call a qualified electrician. +

    Nothing more to be said..
     
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  12. killivolt

    Thread Starter Active Member

    Jan 10, 2010
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    I wish I had a wheelhouse :p in anything.

    I'm always asking for more information rather than shooting from the hip.

    That's why I've been asking everyone. I find if I can ask the right questions even people who are very knowledgable learn something new.

    Anyway, a friend of mine in another forum, well respected directed me to this...

    I had already checked it out in my Google searches before this post but, didn't want to post it yet. He just confirmed it.

    Input 110/220v and output 110v/220v 1800 watts after conversion is around 15amps.

    What do you think?

    http://www.voltage-converter-transformers.com/product_info.php?category_id=10016460&products_id=10060365

    Edit: That's providing when he gets his Unit that the Amperage rating is within 80% I really think the guy that told me it draws 9-10amp is accurate, when he gets it I will verify before he attempts a purchase.
     
  13. inwo

    Well-Known Member

    Nov 7, 2013
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    Don't settle for 240 conversion. If you buy a transformer get the right one.
    120/208.
    I can find you one if you like.

    One other thing you need to know is, if load is continuous.

    A transformer is the one device that can be under sized if load is not continuous.

    Another way to look at it is, dry transformers can be loaded to 125% for short periods. Longer if cooled.
     
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  14. inwo

    Well-Known Member

    Nov 7, 2013
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    1800 watt 120/240 = 7.50 amps to device
    1800 watt 120/208 = 8.65 amps to device

    See what I'm getting at?

    8.65 X 125% = 10.81 amps

    If it runs full bore 24/7 it won't cut it either way.

    100% of all appliances I've tested draw less than nameplate wattage.

    ps.
    If only auto mileage worked that way :D
     
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  15. MaxHeadRoom

    Expert

    Jul 18, 2013
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    If it runs at 8-9 amps on 208, it will be double that on a 120v sourced outlet with transformer.
    That link you point to, that unit will not support that wattage.
    I just fixed a neighbor of mine up that had a similar problem, he had a 240v dryer plug he was not using as he had a gas dryer.
    Ask your associate if he has a similar outlet he is not using.
    Max.
     
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  16. inwo

    Well-Known Member

    Nov 7, 2013
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    A 20 amp 120v circuit can be safely loaded to1920 watts continuous. (Using 120vac)

    I would be very surprised if it would not handle your load.
    Only a loaded test will tell.
     
  17. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    You CANNOT use a single 110v circuit...no matter what "magical box/transformer" you find..
     
  18. inwo

    Well-Known Member

    Nov 7, 2013
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    More or less!

    Not insignificantly less converting to 208 versus 240.
    It may be enough to make it work on a 20 amp circuit. IMHO
     
  19. inwo

    Well-Known Member

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    I disagree. :)
     
  20. killivolt

    Thread Starter Active Member

    Jan 10, 2010
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    It's not and air-conditioner or a cloths dryer or anything with a hewing element.

    It's a Server but, will be running continuously. I'm still very doubtful about how many watts or amps the thing will be running at, as I said before I think the guy is just pulling number out of a hat.
     
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