How to test for maximum wattage of an AC power socket?

Discussion in 'Test & Measurement Forum' started by Amorphous, Dec 5, 2018 at 4:57 AM.

  1. Amorphous

    Thread Starter New Member

    Oct 16, 2015
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    Hi,

    I want to check the max supported wattage (output) of a smart plug to check if it is suitable for use with heavier appliances. Is there any test equipment I can use to simulate an AC load of 2000+ Watts or 10+ Amps @ 240 Vac?

    Thanks in advance
     
  2. ericgibbs

    Moderator

    Jan 29, 2010
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    hi,
    You could use a 2KWatt electric fire. They are usually two 1KW elements in parallel.
    E
     
  3. Reloadron

    Distinguished Member

    Jan 15, 2015
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    I would run with Eric's suggestion of using heaters, I like the reference to "electric fire". I would also suggest that when doing your testing you instrument your plug/outlet connector to monitor temperature rise over time under given loads. A connection which seems fine when plugged in may start getting warm and begin to fail after a period of time. Temperature rise of the connector over time can be an issue.

    Ron
     
    rsjsouza likes this.
  4. rsjsouza

    Member

    Apr 21, 2014
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    Following Ron's suggestion, you can always attach one of those Kill-a-watt meters, which monitors lots of parameters.
     
  5. MaxHeadRoom

    Expert

    Jul 18, 2013
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    That is British terminology for you.;)
    Like Torch for flashlight, (I could go on).:p
    Max.
     
  6. Reloadron

    Distinguished Member

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    Yes, you hang around here you learn all sorts of neat things. :)

    Ron
     
  7. Reloadron

    Distinguished Member

    Jan 15, 2015
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    I have one or two and gave that suggestion some thought but unless newer ones are better the older ones only get to about 1875 VA and the thread starter was looking at 2 KW. The early ones were also 120 VAC versions I know they did start making 220/240 volt flavors but I don't know their limits. Would be a nice solution though. Inexpensive and off the shelf.

    Ron
     
  8. spinnaker

    AAC Fanatic!

    Oct 29, 2009
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    Here is a dumb question. Why not just look at the specs of the smart plug and see what it will handle?

    "Testing" the plug for "supported wattage" is a good way to burn your house down.
     
  9. spinnaker

    AAC Fanatic!

    Oct 29, 2009
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    Also those smart plugs might not be suitable for appliances. They are typically used for electronic equipment like televisions, computers and stereos. I can't imagine why you would want to smart plug an appliance.
     
  10. ebp

    Well-Known Member

    Feb 8, 2018
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    You can demonstrate something is unsafe if it catches fire while you are testing, but no simple test is adequate to reasonably assure long-term safety.

    My advice is to buy only smart plugs that you are absolutely certain have been certified by a recognized safety agency, which leaves out a lot of stuff sold on ebay, Amazon and the like, and are clearly marked with ratings. Don't assume because it looks like it has certification that it has. Lots of Chinese vendors simply put on approval markings that are completely fraudulent. I've seen wooden toys with FCC certification stickers (and doubtless wooden toys don't generate a lot of radio frequency interference).

    Poorly designed electrical sockets lose contact pressure after a number of mating cycles. This leads to increased resistance that can lead to high temperature and possible fire hazard. The risks with smart plugs, because there are generally no exposed metal bits or shock hazard via a non-power electrical connection, are almost entirely related to fire.

    ---
    I disparage Amazon because Amazon in Canada "fulfills' orders for other actual sellers, and there are lots of products that do not meet the legal requirements for sale in Canada, as far as I have been able to determine. I've inquired of a number of vendors about safety agency approvals and get answers like "Trust us. We sell lots of these." Well ... no.
     
  11. Amorphous

    Thread Starter New Member

    Oct 16, 2015
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    I should have clarified in the opening post itself, the smart plug currently comes in <1500 W version, and the manufacturer is making a 2500 W version for a client of mine so I need to independently check whether it will hold itself at those wattage or not.

    Thanks Eric, I will look for a 2.5KW rated heater and run it.
     
  12. ArakelTheDragon

    Well-Known Member

    Nov 18, 2016
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    This is dangerous, keep it under your supervision for the first week at least!
     
  13. Amorphous

    Thread Starter New Member

    Oct 16, 2015
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    Will test it for a minimum of 2 weeks before handing it over to a test facility. They want me to do a preliminary qualification test before spending the money at a professional test fac.
     
  14. ArakelTheDragon

    Well-Known Member

    Nov 18, 2016
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    The best option for tests done by someone (at home or work) is to have a setup environment for that. If you intend to do this on a regular basis, it might be better to start setting up the environement (this should be your next thread).
     
  15. Amorphous

    Thread Starter New Member

    Oct 16, 2015
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    Yes I am thinking about that too. I have a decent setup for DC devices, mostly USB chargers but nothing much for AC devices.
     
  16. kubeek

    Expert

    Sep 20, 2005
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    If the switching device inside is already tested (say a normal relay) then you could simply test with just the current corresponding to those 2kW, without the need to waste that much energy into heat. Power supplies that can do 20A into a short circuit should be easy to find.
     
  17. ArakelTheDragon

    Well-Known Member

    Nov 18, 2016
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    What I meant is you should consider the safety procedures needed and implement them.
     
  18. BBee

    New Member

    Thursday
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    I would suggest, as mentioned above, looking at the rated loading first. These days though, I would be careful as many producers, especially counterfeit from the far east, run very close to the limits. Also be aware that the loading may well be ok for DC or effective DC load, but inductive loading could well cause problems.

    Tracy
     
  19. KeepItSimpleStupid

    Distinguished Member

    Mar 4, 2014
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