Relay always fails same location in the house

Does anyone have any ideas as too why a smart socket would fail (relay stuck closed) powering a certain load?

I have gone through quite a few smart sockets in the same location my media rack in the living room

i have moved house and they still fail there so its not the sockets or power coming out the wall

Its always the same failure the relays get stuck closed and the smart socket thinks it’s toggled the power

It must be the load attached too the socket but its well within the ratings normal extension amplifier, pc, xbox, wii, switch?

Anyone have any ideas?

Presumably the relay contacts have fused together. Usually this is because the load is too high, or the parts are poor quality, or both.

You’ve gone through a few: have they all been the same brand and model?

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This will be about surge load, or inrush current. Many devices will draw a brief but large current pulse at start up, can be an order of magnitude larger than normal steady current. Enough to weld apparently adequate contacts.
Bigger relay or less load.

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Yes im pretty sure its that the only thing that turns off the power is killing the mains

Not during normal operation i have checked the power etc they are 13A 2000w sockets nowhere near that current been pulled

All TP-LINK KASA sockets different models the original hs100 & hs110 (energy moniter) & KP103 MINI

I can’t really argue here but the devices are pretty standard and not high powered

Denon AVR
Low powered PC (HTPC)

Avr always on pc mostly others all in standby until used 13A socket 2000w

AVR on now with HTPC rest in standby under 100w

The toroidal transformers that we used to find in quality audio gear have whopping inrush currents.

Switch mode power supplies too, unless carefully designed.

You might divide and conquer - instead of trying to deal with multiple inrush, use multiple switches?

As @rossko57 said, it’s about the surge load, not about the normal draw.

Have you seen Apollo 13? There’s an ongoing sequence with Ken Mattingly (Gary Sinise) trying to figure out the right order to turn on the capsule’s systems so that they won’t go over the available amperage in their batteries. He needed to turn on a system to see if it spiked (the surge load) too high, and then make sure there was still enough current to allow for subsequent systems to turn on and spike.

Another example: when I was in high school I was learning to do theatre lighting design and someone told me to turn on a stage light. Unfortunately, I didn’t yet know that it had to be done gradually, so I flipped it right to maximum power and blew out the bulb. I sent too much current too quickly, and the bulb couldn’t handle it.

Since all of your devices are going through the Kasa, when you turn it on they’re all suddenly drawing current at the exact same time…and same as the stage light, all it takes is a moment. That’s why fuses typically blow right when you turn something on, or turn your heater/AC/vacuum/hair dryer to maximum.

Even if devices go directly into a standby state when plugged in (and require you to manually turn them on), they can still draw a lot of initial current.

Why do you have all of those devices going through a single smart plug, anyway?

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