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Converting baby swing from battery power to DC adaptor.

  1. Dec 14, 2013 #1
    I have a fisher price baby swing. It has 4 1.5v batteries of size D. I tried to convert it to a 6v DC charger but that didn't work. The charger specification is output=400mA 2.4VA. If someone can help me please to find a right charger as this doesn't work correctly and swing does not swing as swings with the batteries. Swing becomes more noisy and does not swing.
  2. jcsd
  3. Dec 14, 2013 #2
    It's likely the swing is drawing current for a quarter cycle or less. If so, the momentary current drain may be over 400 mA. If you have a voltmeter, monitor the voltage while it's running and if you see the voltage drop significantly below 6 V, try a larger charger.
  4. Dec 14, 2013 #3
    Thanks for the reply. I'm quite a lay man in case of electronics and don't have any mentioned tools to check current. Can you please kindly suggest that what likely be the mA of the adaptor should be. I can open swing to see if any chance there has been anything printed by the swing motor ? Or by some other means Igbo can get help to know about the closest mA that this swing needed please!
  5. Dec 14, 2013 #4
    I can't think of any other options than getting a larger charger. You may find some wall warts that will supply 1 or 1.5 amps. If that doesn't solve the problem I'd look for another problem like maybe your charger isn't working or it's hooked up wrong.
  6. Dec 14, 2013 #5
    I have also tried charger of out 500mA also 600mA but results are not different than the 400mA adaptor. Should I go beyond the 600mA or less than 400mA? If someone can help me please!
  7. Dec 14, 2013 #6


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    You probably need a supply that doesn't have all the a.c. ripple. The ripple is probably causing the noise problem.
  8. Dec 14, 2013 #7
    I tried to search fisher swing that works with DC adaptor and their they mentioned the adaptor having 100mA. Should I try one of similar power?
  9. Dec 14, 2013 #8


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    No, a basic 100 mA adapter will perform worse than the ones you have tried.

    Or maybe you meant to type 1000 mA there?
  10. Dec 15, 2013 #9
  11. Dec 15, 2013 #10


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    I think your best course is to use 1 or 2 sets of rechargeable cells, NiMH type. Have one set on the charger while the other is in use.
  12. Dec 15, 2013 #11
    The fact that the product operates on D batteries indicates that it draws a lot of current. Trying to run it on the charger won't work - you would need a real high current power supply. The charger is for charging - at low current. BTW, anything labeled "2.4VA" is outputting AC - "VA" is a rough AC equivalent of DC watts.
  13. Dec 15, 2013 #12

    Not true. The charger is labelled for its input requirements, not output. The rating is in VA because the input is to a transformer. If what you said was true, how would the charger charge D cells?
  14. Dec 15, 2013 #13
    I never said that charger is charging D cells but an adaptor to replace batteries.
  15. Dec 15, 2013 #14
    Looks like it says output to me.

    There are a bazillion types of wall warts. Some of them do indeed output AC. And the quote above does not seem to match the image that was posted.
  16. Dec 16, 2013 #15


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    So, when you say "charger" you mean "adaptor", then?
    Your average D cell will have about 1AHr in it so if your swing will work with batteries for about 1 Hr, it will be taking 1A. (You could resolve the question with a DMM, of course). You can buy a 6V DC 1A power supply for very few GBP, or equivalent, on eBay. It is important that it should be explicitly marked as a DC supply and that it's connected the right way round. Don't be offended by my pickiness - I have made all those mistakes myself in the past and I always run through the checklist when I connect power to things. Problem is that there are so many varieties of PSU around these days.
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