We have a circuit that runs from the downstairs breaker box to an outside receptacle. This receptacle has 2 outlets. I have many strings of lights and lawn ornaments to be powered from these 2 outlets.
Does it matter how the power is distributed? e.g. could all the device be connected to one outlet? Or should I try to balance the load across the 2?
I’m thinking it doesn’t really matter how things are wired, the only problem I’ll have is if the total demand is over 15 amps.
Most duplex outlets both are on the same circuit, but it is easy to wire them to 2 circuits. If things aren’t labeled, you would have to flip breakers to tell. If both are on the same circuit, it makes little difference how you arrange the plugs.
Nearly all our Christmas lighting inside and out is on one 20 amp circuit. However, it is mostly CFL and LED. I doubt if all together it is 100 watts.
With the incredibly low-draw LED Xmas lights now sold, you could probably light your entire house, à la Chevy Chase in Christmas Vacation, off one 15A outlet!
Note that a lot of Xmas lights are designed for stringing end to end. But they have individual limits on how many you can daisy-chain like that.
So it may be that your single outlet of a duplex pair can handle all, say, 12 amps, but one of the downstream items can’t handle having 8 more amps hanging off the back of it. Every car in a railroad train has to be strong enough to drag the rest of the train behind it.
If you use extension cords and 1-becomes-3 outlet splitters, you also have to consider their ratings versus what’s hanging downstream off them.
Finally, at the duplex outlet itself …
While each female connector in the a duplex outlet is rated for the full 15A, there will be less heating if you split the load between both receptacles. One of the weakest points in a typical household circuit is where the female receivers clamp onto the male prongs inside an outlet. Deliberately trying to extract max performance from that spot when you don’t have to is setting up a greater likelihood of problems.
Converely, if you know one of the two outlets has poor grip, you might do better to run all 12 amps through the better one rather than put 6A through the good one and the other 6A through the one with bad grip causing intermittent micro-arcing. Better yet, replace the receptacle.
