Step Down Transformer Troubles

steven123steven123 Posts: 3,245
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I recently purchased a Japanese Neo Geo CD (90s games console). As it is a Japanese unit it's AC adapter runs on 100V not our 240V but it came with a Step Down converter so no problem, or so I thought...

Basically, first few times I used it, it worked perfect, played it a good few hours, seemed solid as a rock. Switched the console off (but left the AC lead connected) and watched the TV. Couple of hours later the TV shuts off with no warning (I have an 8 way intellipanel surge protecter, the type where it switches everything on/off via the TV remote).

I switch on the TV again and within a few minutes it cuts off again. I remove the step down and neo geo and turn on the TV again and it doesn't shut down, suggesting a problem with the step down / neo geo.

I think the step down may be inadequate for the Neo Geo as when I looked on the step down it says it can do 30VA indefinitely and 45VA as a max for not more than 1 hour. However on the neo geo AC adapter it says that it needs 55VA! Which appears to be significantly above even the max level of the step down?

EDIT: the step down I have seems to be identical to this one: http://www.amazon.co.uk/Stepdown-240-120V-Transformer-45VA/dp/B000NJ26X2/ref=cm_cr_pr_product_top

However, this being the case, how come it worked fine for a number of hours and only actually caused the power strip to cut out when the console was off? (and hence it would not be loaded surely?)

So, have I broken the step down, or worse still the console :cry: (which wasn't cheap)? and do I need another step down adapter?, or is there some way I can get a UK adapter that will work with the Neo Geo CD so I don't have to use these dodgy step downs at all?

Any advice gratefully received.

Comments

  • OrbitalzoneOrbitalzone Posts: 12,627
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    Presumably the original power adaptor convered 110V to something like 12v dc? - one of those black plastic brick power supplies?

    If so then it should be possible to replace with a UK version... the problem is finding one with the right connection, volts and current rating (is it a 3 pin like this?)

    I'd advoid those cheap and nasty drop down converters, it sounds like it's underrated for what you need and they're pretty crap anyway.

    Edit: seen this?
  • steven123steven123 Posts: 3,245
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    Presumably the original power adaptor convered 110V to something like 12v dc? - one of those black plastic brick power supplies?

    If so then it should be possible to replace with a UK version... the problem is finding one with the right connection, volts and current rating (is it a 3 pin like this?)

    Yes, that image shows the exact console I have with the mini 3 pin input for power. I have looked on the back of the power supply and it says:
    SNK AC Adapter POWCD-J
    AC 100V 50/60HZ 55VA
    DC 5V 2A
    DC 10V 1A

    and there is a little diagram of the three pins: top is 5V, left ground and right is the 10V.

    Really hope I can locate a suitable adapter.
  • steven123steven123 Posts: 3,245
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    That looks good, they have the exact adapter I need by the look of it, do you know if the seller is reputable?

    Also do you think there is much danger that the step down damaged the console?

    Nothing went bang (the adapter didn't even get hot) it just shut down the surge protector so hoping the console is still fine.

    That adapter isn't cheap but Neo Geo stuff is so rare these days one can't be picky, I have a good mind to make the seller pay for it since I'm none too happy with the seller as it seems they have given me a step down that simply wasn't up to the job, in addition the console came with smashed game cases (on the four bundled games) and an RGB Scart that ghosted horribly (I ended up using the composite which was actually much better!)
  • chrisjrchrisjr Posts: 33,282
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    steven123 wrote: »
    Also do you think there is much danger that the step down damaged the console?

    Nothing went bang (the adapter didn't even get hot) it just shut down the surge protector so hoping the console is still fine.
    If any damage were done it would far more likely be to the step-down transformer. But I would not be over bothered about the fact that the transformer appears to be underrated.

    If the specs of the power supply you have provided are correct then the power supply is nowhere near 55VA. 5V@ 2 A and 10V @ 1A totals 20VA. Even the most inefficient power supply known to man would not need 55VA at AC to provide 20VA at DC. So the 30VA continuous rating of the transformer is probably OK.

    If the power supply really was dissipating 35W of waste energy then I would expect it would get very hot in use. If however it stays relatively cool, ie only slightly above room temperature and nowhere near too hot to handle, then I very much doubt it is drawing 55W from the mains. Also the transformer would be getting warm as well if it was drawing more than it's designed current for any length of time.

    And I would hope that it has a protection fuse that would pop if it were being overloaded. So if the transformer didn't get hot either then chances are it is OK. Or at least not being overloaded unduly.

    That does not however exclude the possibility that the transformer is dodgy in some other way and that it caused the shutdown of the power. What actual make and model of 8 way power strip do you have? Is it one of those that senses current drawn on a certain socket and if that falls below a certain threshold it turns everything off? If so could it actually be sensing on any socket and when you power off the console it senses that and turns the whole lot off as well?
  • steven123steven123 Posts: 3,245
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    chrisjr wrote: »
    If any damage were done it would far more likely be to the step-down transformer. But I would not be over bothered about the fact that the transformer appears to be underrated.

    If the specs of the power supply you have provided are correct then the power supply is nowhere near 55VA. 5V@ 2 A and 10V @ 1A totals 20VA. Even the most inefficient power supply known to man would not need 55VA at AC to provide 20VA at DC. So the 30VA continuous rating of the transformer is probably OK.

    If the power supply really was dissipating 35W of waste energy then I would expect it would get very hot in use. If however it stays relatively cool, ie only slightly above room temperature and nowhere near too hot to handle, then I very much doubt it is drawing 55W from the mains. Also the transformer would be getting warm as well if it was drawing more than it's designed current for any length of time.

    And I would hope that it has a protection fuse that would pop if it were being overloaded. So if the transformer didn't get hot either then chances are it is OK. Or at least not being overloaded unduly.

    That does not however exclude the possibility that the transformer is dodgy in some other way and that it caused the shutdown of the power. What actual make and model of 8 way power strip do you have? Is it one of those that senses current drawn on a certain socket and if that falls below a certain threshold it turns everything off? If so could it actually be sensing on any socket and when you power off the console it senses that and turns the whole lot off as well?

    Yes, I think the transformer probably is powerful enough after all as I got in touch with the seller and he said it had always been fine and that he actually bought the console with that stepdown suggesting it really is of the correct spec (the seller is still selling the consoles and has no negative FB, see here: http://www.ebay.co.uk/itm/JAP-SNK-NEO-GEO-CD-CONSOLE-SET-BOXED-DOUBLE-DRAGON-GAME-JP-Japanese-Neogeo-/170985487432?pt=UK_VideoGames_VideoGameConsoles_VideoGameConsoles&hash=item27cf877c48 ). Plus on the back of the console it says it draws 29 watts (which is well within the 45 watts of the transformer and probably a maximum anyway i.e. it might use less sometimes).

    By the way the step down is actually made by mercury and you can see the exact one on their website: http://avsl-mercury.com/product/651.001UK it goes for a whopping £5.99 ;) but if it's enough for the job...

    The seller did say he never used it with a surge protector though and that I should try it direct into a socket. However, I am a bit wary of that because if it is malfunctioning in some way, could it blow the fuse in the socket or worse still something at the main electricity supply?

    The 8 way power strip is this exact one: http://www.oneclickpower.com/pdf/OneClickIntelliPanelTVA206.pdf it has a master socket for the TV and when you put the Tv to standby it shuts everything else off after about thirty seconds, but only the TV should be able to do this, it shouldn't matter whether any of the devices in the other sockets are on or off.
  • Nigel GoodwinNigel Goodwin Posts: 58,437
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    The problem here 'may' be that it's NOT a transformer? - there are various cheap 'converters' about which use switch-mode techniques to supply a lower voltage device from 240V mains.

    These don't work with all devices, and don't provide proper sinewave mains.

    A real transformer should work with no problem.
  • OrbitalzoneOrbitalzone Posts: 12,627
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    Yeah that's a good point, something computer based may not play well with a chopped up supply.
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