Looking for ideas / suggestions on how to do this smartly - I have the following scenario:
I live in a renting environment where I am the landlord and room-mates/tenants pay a fixed cost per week for power.
In our laundry we have a clothes-drier and washing machine (two separate appliances) connected to the same 2-outlet power socket on the wall.
Unfortunately, the clothes drier costs about 1/2 the weekly power allowance if left to run for a full cycle (180 minutes). It’s an old model with a simple dial to set the run-time.
The tenants have been told on multiple occasions that 30-45 minutes is sufficient for a full load, and that it should be occasionally only. However, I am certain that it is being used for crazy amounts of time (and thus cost) while I am away at work during the day, and late at night etc as I have caught it running on multiple occasions.
So, what I want to do somehow is limit a maximum cycle of it to 45 minutes. Or come up with some other ‘smart’ way of monitoring the exact power usage so that I can on-charge the cost while being sure that I can identify who used it (I can already tell who is home thanks to phone mac address)
Bear in mind that the washing machine is also on the same circuit so don’t want to disable this mid-cycle if possible.
Tossing around the idea of a Sonoff switch inside the wall but not sure what sort of rules/configuration I could put around it?
to be honest, if you even find a way to stop the dryer after 45 min on one of the sockets, it won’t be long before your tenants realise it’s linked to one socket only and then plug the dryer on the other socket?
The other way round would be to have an inline controllable socket on the dyer cable (since it’s old I guess it’s no longer under warranty), but:
You need a device that will monitor power usage
You need to make sure the device will accept big loads (dryers use a LOT of power)
You need to somehow reset the “counter” so that after a successful 45min your tenants could run another load (how you’ll know if it’s the same load going for 2nd time or a new load is another way for them to “beat” your system).
So with all this in mind, maybe you only use an energy monitor that would somehow be built in line on the dryer (again to avoid a swap of the cables on the socket), and then maybe add some sort of charge back to their rent if they overuse the dryer?
I’ve not looked as energy monitors that would fit such method of installation though so not even sure they exist, but I would be surprised if there wasn’t one out there
Thanks, you’ve hit on pretty much all the scenarios I have been running up against.
The laundry room has a single power outlet, with the two sockets. These are a single feed, so if I put a switch on the outlet I’m affecting both sockets.
I need to investigate what’s out there. Obviously a smartplug could do it, but that’s easily bypassable…
True.
They shouldn’t be running more than one load at a time, ever. If they’re running more than a couple of loads a week I need to increase the rent. So I need to know in either case.
I am thinking about the following, which although not automatic would at least allow me a degree of control.
Put a high-current Sonoff behind the socket.
Put a meter behind the socket too.
Have a power monitor alert me when the dryer has been drawing for more than 45 mins - I can then choose to disable the dryer remotely.
Have the power automatically restore at times of the day I’m likely to be home, so that I can have checked to make sure they dryer is turned off by the time power comes back on.
the way I would attempt to do this is ideally an in line energy monitor / controllable device (like a sonoff indeed, if they have a version that gives you power usage) so that it can’t be tempered with (to avoid the tenant connecting the dryer to the other power outlet and bypass the whole setup)
It looks like a Sonoff Pow might be what you’re after:
16A so should be good enough for the dryer, and built in energy monitor. Install Tasmota on it and you’re good to go.
Just one note: it appears recent Sonoff Basic can no longer be flashed with non Sonoff firmware, so you may want to double check that first.
You could use something like the aeon labs smart switch 6 to monitor when there’s a load, and then turn it off after xx minutes. Very easy to do. This would be easy for someone to circumvent, but it would at least prevent absentmindedness. Same goes for a GE z-wave smart outlet (but at least it would be built in).
A sonoff in the wall sounds like a good way to burn down a house and kill a tenant. Consider the trade-offs re: dryer problem solved v. lawsuit.
Alternatively (which I would much more strongly recommend), you could get a new, more efficient dryer, or re-negotiation the utility billing scheme.