What is the difference between both of them? There was a post similar to my question, but there was no answer about resistive wattage.

I want to buy a wifi outlet and I need to make sure it doesn't burn like my last one when I plugged it to my AC. I saw this new outlet. The ratings on the outlets are: 15A / 1875W Resistive 5A/ 625W Tungsten 125V/60Hz

my Air Conditionner ratings are: 8.4 A SCE/EER 9.4 WATTS 851 BTU 8 000

Last time my outlet stopped working but it was 10Amps, will this 15Amps one work?

Link to my AC ratings

Link to the outlet ratings

Picture of the outlet - Front view

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    a) Can you add a link or model # for this new outlet? b) tungsten == incandescent bulbs, which is (AFAIK) basically a resistive load. An air conditioner is a motor - very different type of load. I'd be skeptical about putting that on anything but an ordinary receptacle. c) Why do you need WiFi to control your air conditioner? – manassehkatz-Moving 2 Codidact Apr 9 '19 at 1:45
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    What are the WiFi switch's motor ratings? If that's not listed, does it state a ballast rating? Can you link the product? (Switch)? You can edit your question to add that info. – Harper - Reinstate Monica Apr 9 '19 at 5:59
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    @manassehkatz: a) I've added pics, b) refer to a, c) so I can turn on the AC before I arrive home and it's cold in during summer time. – Conrad C Apr 9 '19 at 22:51

Tungsten loads have inrush issues resistive loads don't

Tungsten (incandescent/filament) light bulbs have a positive temperature coefficient of resistance. This means that as the bulb heats up during operation, its resistance increases, and thus the current drawn by the bulb decreases. This inrush current when turning on a cold bulb can be a significant multiple above and beyond the steady-state load, and thus requires the relay contacts to be derated from their resistive load handling capabilities in order to avoid excessive arc wear/damage to the contacts.

Furthermore, air conditioners are a whole another animal

Your air conditioner is neither a tungsten nor a resistive load, though. Since it uses an AC electric motor to run the internal compressor, it is a motor load with a very inductive characteristic. This also means it's quite heavy on the inrush current as well, with a typical AC motor having a locked rotor starting current several times that of its full running current, and thus requires a different rating for the control switch as well. This rating is usually given in terms of the horsepower of the largest motor that the device can safely control, so it is often called a horsepower rating as a result.

Furthermore, air conditioners have special properties that weigh against controlling them remotely by pulling their plug out. In particular, this can defeat protection systems in the air conditioner that prevent it from short cycling, and for heat pumps, this can be a more serious issue yet due to loss of power to key accessories, such as crankcase heaters.

As a result, it's generally considered Not A Good Idea to use a switched outlet to control an air conditioner. You are better off finding a way to hack the controls to do what you want, so that they can handle situations like short-cycling properly; furthermore, since your outlet lacks a horsepower rating, it's not rated to control any sort of motor load to begin with, which makes using it to control this an extra-bad idea.

  • Interesting, thanks. I've added pics of the outlet if it can help answer my questions about the specs. – Conrad C Apr 9 '19 at 23:06

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