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Home Assistant waters my plants

finnian.io

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Re: Home Assistant waters my plants

#11

Post by atoav »

zerof1l wrote: post #8

I wanted home assistant compatible plant watering solution that works on a solar panel and does not require being connected to the water line and is Zigbee compatible. Unfortunately, I could not find any. So I did a DIY solution: a big barrel which I manually fill with water, a 12V pump (usually sold for camper vans), some rechargeable batteries, 10W solar panel, a solar charging controller, and Tuya ZG-2002-RF switc…

An art student of mine once needed a way to electrically control precise small amounts of water. We solved that using:

  1. Water tank and gravity  
  
  2. Medical IV flow regulator¹  
  
  3. Servo hooked up to that IV flow regulator via a 3D-printed part
It worked very well. In medical applications off must be really off, so it was also quite safe in that regard as well. Her 3D-printed part had a little bit too much flex in it, but in principle this works quite well. If it is really, really safety critical I would still recommend a mechanical fallback that protects in case of power loss or when the servo fails open (e.g. bending the hose with the force of a spring if electricity is gone).

¹: see https://www.gvs.com/en/catalog/iv-flow-regulators

Re: Home Assistant waters my plants

#13

Post by ga_to »

squigz wrote: post #9
calgoo wrote: post #5

Earlier quoted context omitted.

Exactly! I prefer the small power plugs that lets me control fans and other power systems as relays. Family has a habit if switching of light bulbs using light switches and i have not gotten the change approval to disable the physical switches in the house :)

It seems like quite the hassle to have to pull out one's phone every time one enters or leaves a room just to turn on lights? Let's hope you don't have to get to the bathroom quickly late at night...

Disabling the physical light switch should usually only come after setting up a different way of controlling the light by hand, without a phone.

Most likely there is some sort of motion or presence sensor that turns on the lights which then turn themselves off after some time or no more presence is detected. There are also small wireless switches that could be used in place of the actual wall switch.

I have done so in my apartment for example. Since the bedroom light switch is for some reason outside of the room I taped it down and put a wireless switch in a more reasonable spot. Another example is the hallway light, which only turns on by motion sensing when the sun is starting to go down.

Re: Home Assistant waters my plants

#14

Post by stinos »

atoav wrote: post #11
zerof1l wrote: post #8

I wanted home assistant compatible plant watering solution that works on a solar panel and does not require being connected to the water line and is Zigbee compatible. Unfortunately, I could not find any. So I did a DIY solution: a big barrel which I manually fill with water, a 12V pump (usually sold for camper vans), some rechargeable batteries, 10W solar panel, a solar charging controller, and Tuya ZG-2002-RF switc…

An art student of mine once needed a way to electrically control precise small amounts of water. We solved that using: 1. Water tank and gravity 2. Medical IV flow regulator¹ 3. Servo hooked up to that IV flow regulator via a 3D-printed part It worked very well. In medical applications off must be really off, so it was also quite safe in that regard as well. Her 3D-printed part had a little bit too much flex in it, b…

> If it is really, really safety critical

Your suggestions should be fine for hardware failure but I'd be more concerned about software failure: what if a bug in your software makes it unresponsive and stuck in the state with the flow open? Maybe a watchdog or some other system running in parallel checking for a heartbeat or a max amount of time water can be flowing?

Re: Home Assistant waters my plants

#16

Post by H8crilA »

longtermemory wrote: post #2

Nice! For the hardware, why didn't you considered using a Raspberry Pi?

I used to run HA on an RPi, but eventually migrated it to a similar NUC. The RPi eventually just wasn't powerful enough (peak compute needs), while the NUCs are still quite cheap. And you can run a surprising amount of Proxmox VMs and LXCs on barely a few cores and gigabytes of RAM.

Re: Home Assistant waters my plants

#17

Post by davemp »

Fun project. Though it’s kind of unreal how complicated it is to set up HA and I literally do this for a living, both embedded sw and backend web dev.

Docker compose with a zwave management server, reverse proxies for TLS, vlan isolation for the server, macvlan for HA container so it does see the host network, etc, etc. All to turn on and off a lightbulb with the sun. All the while AI is telling me to configure things insecurely.

I think when I get some more spare time, I’d like to write a statically linked program that handles a zwave controller and basic automation scripting. No IP networking needed for my lightbulbs. Then it wouldn’t feel risky to just make a system user and udev rule to give it permissions to the controller, and run with systemd.

Re: Home Assistant waters my plants

#18

Post by davemp »

H8crilA wrote: post #16
longtermemory wrote: post #2

Nice! For the hardware, why didn't you considered using a Raspberry Pi?

I used to run HA on an RPi, but eventually migrated it to a similar NUC. The RPi eventually just wasn't powerful enough (peak compute needs), while the NUCs are still quite cheap. And you can run a surprising amount of Proxmox VMs and LXCs on barely a few cores and gigabytes of RAM.

I use an RPi 4 w/ 4GB of RAM and a 1TB usb 3.2 SSD and it flies through all my workloads. Though I don’t do any video encoding things.

Re: Home Assistant waters my plants

#19

Post by PetitPrince »

squigz wrote: post #9
calgoo wrote: post #5

Earlier quoted context omitted.

Exactly! I prefer the small power plugs that lets me control fans and other power systems as relays. Family has a habit if switching of light bulbs using light switches and i have not gotten the change approval to disable the physical switches in the house :)

It seems like quite the hassle to have to pull out one's phone every time one enters or leaves a room just to turn on lights? Let's hope you don't have to get to the bathroom quickly late at night...

As a another comment said, the smarter way to have a smart light is to replace the switch with a smart one or even better put a relay behind the existing dumb switch to smartify the switch. For me it's important to have a manual override; you shouldn't need an app for a thing as basic as turning the lights on.

Re: Home Assistant waters my plants

#20

Post by mytailorisrich »

H8crilA wrote: post #16
longtermemory wrote: post #2

Nice! For the hardware, why didn't you considered using a Raspberry Pi?

I used to run HA on an RPi, but eventually migrated it to a similar NUC. The RPi eventually just wasn't powerful enough (peak compute needs), while the NUCs are still quite cheap. And you can run a surprising amount of Proxmox VMs and LXCs on barely a few cores and gigabytes of RAM.

Wow, not sure how to interpret your experience that a RPi wasn't powerful enough to manage watering a few plants. I can only suspect the overall software setup is massively bloated.
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