Relay Power Switch for dual kitchen appliance on single outlet

Not Sense, but general electrical question, so hoping the group of people here with all sorts of gadget ideas have thoughts.

Has anyone ever seen a device that you can plug two devices into and set a priority, so if one is running, it turns off the other, then when done, reverts?

Basic premise - small office in large office building = getting any new wiring is very hard.
We want to add a hot water tea kettle to our little kitchenette that consists of a Keurig, ice maker, microwave and water dispenser. We have two x 15amp circuits which is fine now as the Keurig can be on one, the microwave on the other, and then the lower power devices are split.
The hot water kettle is going to start popping breakers if its used at the same time as either the Keurig or Microwave. While one would hope a sign saying “don’t use X if Y is in use” would work, we can’t trust it.

So i’m hoping for a “smart” solution that is actually not all that smart and just mechanical. A long ago in college, I remember you could rent the “micro fridge” from the school. It was an all in one mini fridge with microwave attached to the top. If you were using the microwave, it would cut power to the fridge so the compressor couldn’t kick on. As soon as the microwave was done, it would flip back so the fridge could power up if needed.

I’m looking or something similar. So I can put the tea kettle and the microwave on the same circuit. If Microwave turns on, power to tea kettle gets cut. Internet searches have been been tricky as you can see how many words it took to explain this and I can’t find the right keywords other than “relay”. Ideally I’m looking for something that exists, not a custom build as this will go into the office and they are less likely to like a custom electrical project.

Anyone know of anything like that, or of parts that cold go together in a somewhat easy fashion that doesn’t look too home made?

How about this:

It appears to support configurable load shedding, see p. 39:

Little spendy @pswired !

Starts to feel like multiple smart plugs can get you there in some fashion.

This could form a cheaper base with some homebrew:

You could go full analog and wire up a 3-way toggle switch to switch 2 outlets, only one being hot at a time. Having just deactivated a switch in an outlet that provides power to my toaster & kettle, you’re giving me ideas! Any electricians gonna be a killjoy with the NEC?

Hard to tell what the OP’s situation is, but the liability caused by using a non-UL-listed devices on business premises would far exceed the value of that mini-ATS.

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Now, in the hypothetical situation that one were doing this at home or in some other nonregulated environment…

That plus a standard 120v 20A rated relay in a 4x4 box with enough volume would get the job done. Add a SO cord whip and receptacle and you’re off to the races.

Thanks everyone for the recs.

The Tripp-Lite PDU is interesting and I may look more into it.
The ADA Fruit switch could be good, but I think it needs more parts as not only the RPI, but also something with current sensing to tell the Pi to switch outlets. Or a push button to manually switch outlets.

Correct that I am looking for a complete / off the shelf solution. While no one in the office would necessarily say anything if I built my own, in the event anything ever happened, I certainly would not want it to be because of my home made contraption. I’m honestly surprised that there isn’t a solution already which makes me think maybe there is a UL issue with the concept. Or is it that unique of of a problem?

Indeed. Guessing that UL (NEC) issues compound with multiple relays and points of failure.

… And why not an HS300 with some Kasa firmware that doesn’t exist yet? Latency in current detection would be too great?

Make a short breakout box extension cable splitter with a fat toggle switch and nice in-your-face office sign like you put in the fridge!

Get rid of the kettle and use the Keurig for hot water?

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[I was stuck in a thought groove based on my single-outlet kettle + toaster needing similar treatment – so all I was *getting* was soggy toast or burnt water]

As a non coffee drinker, I have to veto the Keurig as hot water source. I always feel like the water always tastes like coffee. Yes, usually by the time you toss in a tea bag and honey, you can’t really taste it, but it also depends on how recently the machine was just used. I know if I use a hot chocolate or tea pod right after someone just used a coffee pod, I’ll get that taste, so I usually try to run a hot water cycle before changing to a non coffee product. I appreciate the work around, but…
I also of course wish that Signs would work and am a fan of K.I.S.S., but its an office and for the first day maybe a sign will be followed, but soon people will forget / move on.

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I know what you mean, I drink a good amount of tea and can’t imagine a dual-use device could ever work unless there are separated water paths. I’m also particular about the water vessel and pretty much can only tolerate stainless steel (plastic is nasty; non-stick surfaces break down). Have you considered something like a low-wattage (boil + standby), well insulated boiler?

Check the Zojirushi CD-WHC40

Seems good for an office given the large-ish capacity. And cheaper than a proper PDU!

Nice specs:

Now of course the question is whether the Keurig leaves you with enough watts?
They don’t (go figure) seem to publish the wattage! That’s what Sense is for (thanks @samwooly1):

So apart from the initial 1500W boil, the 245W element should work alongside the Zojirushi.
Of course, it’s an office so it’s not perfect but with the low standby of the Zojirushi, if you got that to boil first thing or anytime after the Keurig startup then you should be safe.

Kinda loving this problem and waiting for somebody to chime in with an obvious solution.

I had a work period where a microwave was the only way to make tea btw. PITA, but it worked.

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