Help needed: Plugged our 120V breast pump into a 220 v outlet

Discussion in 'Technical Repair' started by Dadsmail, Jul 14, 2016.

  1. Dadsmail

    Thread Starter New Member

    Jul 14, 2016
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    Hi all. New to the forum. Hope somebody can help me with my concern. (Perhaps an elementary question to most here) My wife inadvertently plugged her pump into a 220 v outlet. The adaptor (not the pump itself) was warm to the touch but there was no burnt plastic smell. Seems like the adapter was damaged since we tried using a transformer after mistakenly plugging it to the wrong outlet and the pump didn't power up. But it can also be powered using batteries and it works fine this way - the motor still works the way it should. I plan to get another adaptor with universal voltage but I'm worried that something internal is damaged and might have rendered the ac function useless. Could this be the case? Any chance that the only part damaged is the AC adapter? Thanks in advance.
     
  2. SLK001

    Well-Known Member

    Nov 29, 2011
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    Might help to know what the proper AC input should have been. My guess is that it is a 110V unit that was smoked when you plugged it into 220V.

    Women! What are we ever going to do with them??!!
     
  3. KeepItSimpleStupid

    Well-Known Member

    Mar 4, 2014
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    A very good chance it's only the adapter. Pay attention to the polarity of the DC side (if it is DC). Also pay attention to the size of the coaxial DC power plugs (assuming again) A 5.5/2.1 will fit a 5.5/2.5, but not vice versa. The first one will make an intermittent connection. Its easy to overlook and both are common sizes.
     
    #12 likes this.
  4. Dadsmail

    Thread Starter New Member

    Jul 14, 2016
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    Thanks for the replies, folks. Since output is only 4.8V, there's no chance that it went over that when it was plugged to a higher voltage outlet? Here is a photo (borrowed from the web):

    upload_2016-7-15_11-27-45.png
     
  5. MaxHeadRoom

    Expert

    Jul 18, 2013
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    2,373
    I would be interested to know how a 120 volt device was plugged into a 230v receptacle?
    If a N.A. installation this would not normally be possible to do inadvertently due to the different socket standard.?
    Max.
     
  6. Sensacell

    Well-Known Member

    Jun 19, 2012
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    It's called "travel" - a very common cause of failure in non-universal input power supplies. I cannot tell you how many times I have killed things this way.
     
    Last edited: Jul 15, 2016
  7. Dadsmail

    Thread Starter New Member

    Jul 14, 2016
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    Sort of :) Bought the pump while we were in the US, took it home to Asia. Same socket, different voltages. I have an avr for it but the voltage indicators on the avr were etched onto the aluminum plate where the sockets were...really hard to see. Couple that with a tired mom who slept late and woke up at 5 am to pump before heading to work = :confused:
     
  8. KeepItSimpleStupid

    Well-Known Member

    Mar 4, 2014
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    You really need to do two things:

    4.8 V is really weird. 5V 1 A is usually common and will likely work.

    But you need to take a pic of the barrel with cm ruler in the picture and a pic of the center with a cm ruler in the same plane blown up as much as possible with the camera. Clay would be an easy way to take the pic.

    e.g. Clay to hold the barrel and cardboard with a hole in it to put it at aprox the same level as the ruler. An old cardboard box with a hole and tape will work too. Use magnification to your advantage. There are some programs that can measure a JPG once you calibrate.

    I can use a drill bit since I have so many english sizes. I also have a metric/english caliper for the OD.

    if you don't have a ruler use a known size like a US coin. That will work too. That's something I can measure. A metric screw from the hardware store. e.g. suspended with a nut. hex bolt - anything where the size is known. A 10 mm bolt will come with a standard head (for the most parts) and that can be looked up.

    Might be easier to buy a ruler, but my 6" machinist's rulers are expensive.

    Here's https://www.boltdepot.com/fastener-information/printable-tools/metric-hex-bolt-sizes.pdf a ruler you can print. So you can take a 3x5 index card and easily get an inch standard from it to check it.

    It can then be matched to one of these: https://en.wikipedia.org/wiki/Coaxial_power_connector#Adaptaplug
     
  9. Dadsmail

    Thread Starter New Member

    Jul 14, 2016
    4
    0
    I've actually found a replacement specifically made for the model we have. We have a Medela Swing pump. I'm just worried that when we plugged the pump to a 220 v outlet, it might have fried something inside the pump itself, rendering the adapter option useless. The pump itself still works when being powered by a battery. The adaptor isn't available locally. Have to have it shipped from abroad so wanted to make sure that the pump unit wasn't damaged in anyway by what happened before I order.

    Here is the replacement I will be ordering:
    https://www.amazon.com/Maymom-Breas...68559394&sr=8-1&keywords=medela+swing+adapter
     
  10. KeepItSimpleStupid

    Well-Known Member

    Mar 4, 2014
    1,146
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  11. Tonyr1084

    Active Member

    Sep 24, 2015
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    You said you can power it from a battery. Does the battery connect the same way as the wall plug? Or is the battery internal?

    IF (big "IF") the battery plugs in the same way as the wall plug does then there should be nothing wrong inside your unit. Since the plug output is DC then there's not much more inside the pump than the power connection. Maybe a diode to protect against revers polarity (but I guess at this).

    IF the battery is connected different from the wall plug then there might be some diodes internally that could have been affected. Either way, it's probably something that is easily repaired by someone with just a little experience with components and basic wiring.

    It's likely the pump is nothing more than a motor that runs a diaphragm. Therefore, an alternative power source - such as a 5 volt 1000 mA supply (1 amp) could possibly be sufficient to run the motor. Some cell phone chargers supply that much current. I would suspect that if you got the polarity reversed the motor will run backwards, but the diaphragm will likely still pump (vacuum). Breast pumps are pretty basic devices. The diaphragm moves back and forth. Vacuum is applied to the breast and milk will be extracted.

    I think your options are greater than you think. Look around for a DC wall plug. If you have to, cut the cord from the old plug and attach it to the new supply. All will likely be fine.

    One word of caution - before doing ANYTHING anyone here tells you (me included) check to make sure it won't damage anything. I wouldn't want to be responsible for messing up your pump. Still, I think a 5 volt DC supply with sufficient amperage will do just fine.
     
  12. wayneh

    Expert

    Sep 9, 2010
    12,126
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    I agree, and I think it's unlikely that your pump is damaged. I'd use a standard 5V adapter, rated to handle the current, to verify. After that, assuming it works, it's your option whether to buy the new adapter or not. Given that 5V adapters are so easy and cheap to obtain, I wouldn't bother with the fancy one.
     
  13. ian field

    Distinguished Member

    Oct 27, 2012
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    The 4.8V specification suggests that its tailored to charging a bank of 4 nickel chemistry cells.

    Just randomly picking a "universal" adaptor might not be a good idea.
     
  14. wayneh

    Expert

    Sep 9, 2010
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    But I think that was an old-fashioned wall wart, which would be well over 5V when unloaded.
     
  15. ian field

    Distinguished Member

    Oct 27, 2012
    4,415
    784
    And it might be current limited for charging nickel chemistry cells - if its scrap, I'd crack it open and see what's in it before just blindly replacing it with a "universal" wall-wart.
     
  16. wayneh

    Expert

    Sep 9, 2010
    12,126
    3,048
    Ditto that. Might even uncover a blown fuse.
     
  17. Tonyr1084

    Active Member

    Sep 24, 2015
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    I'll second the motion to open the scrap wall wart.

    I'll ask again in case it got overlooked; does it have internal batteries?
     
  18. BobTPH

    Active Member

    Jun 5, 2013
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    Not likely, since NiMH cells charge to about 1.4V each. 1.2V is the nominal voltage. Just like LiIon cells are called 3.7V but charge to 4.2V.

    Bob
     
  19. Tonyr1084

    Active Member

    Sep 24, 2015
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    This wall wart: Is it a battery charger? Are there internal batteries in the pump? I was going under the impression the pump worked from the wall wart. But if it has batteries internally - well, that's my question; does it have batteries internally?

    If not - are batteries something you install? Like AA Alkaline batteries? Maybe C cell Alkaline? Just what are we dealing with?
     
  20. KeepItSimpleStupid

    Well-Known Member

    Mar 4, 2014
    1,146
    204
    Hey. the new wall wart designed for the unit is 5V 1A and not 4.8V at 800 mA.

    We just have a simple question here: Did I likely just damage the wall wart by doubling the mains voltage before the TS spends his hard earned money?

    That's it.
     
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