This is a rack and tray for mounting an Ambient Weather PM2.5 Wireless Outdoor Particulate Monitor outdoors in a way that you can still use it while it's plugged in.
Much of the time, these sensors are solar-powered, and they can be run most places entirely on solar power. However, if you are far enough north and have enough clouds, solar power is not effective any sort of device like this over the winter. Since this device works fine plugged in, the obvious solution is to either recharge it regularly, or just keep it plugged in. But in hot weather, that stresses the batteries via overheating. Also, the charge cord comes straight out the bottom of the battery compartment, creating a very difficult situation in terms of placing the device on any surface when in use. (Think Apple Magic Mouse. Same problem while charging.)
Accordingly, I have designed this tray and rack system to hold the device in a reasonable position for extended periods while driving it with a USB charging cable. Originally, the idea was that you could slide the tray into the rack even with the cord plugged in, but in some plastics the rack became too flexible. So I abandoned that part of the idea. The rest is still good though, and keeping the tray still a separate object allows more refinements by other people and also keeps water flowing away from the electronics of the device.
Please note there are TWO DIFFERENT RACKS. One is for use with the tray, and is for when the battery cover of the monitor has been removed and it's sitting on the tray running while charging or being powered solely by USB. This is the rack seen in the photos. It's right next to an outlet.
The other rack is for use without a tray, as it is exactly the right width for the monitor when fully assembled and running on battery and solar. I have that rack out in full sun, and the monitor just sits on it. The tray mounts are not quite symmetrical and smaller than the charging rack, and the fact that it fits the fully-assembled monitor perfectly was an accident I was happy to use. ^_^ It's sitting out in as much sun as I can get it.
I know this is incredibly niche but if you need it, you kinda really need it. xD
Anyway, as part of my ongoing air-exchange-based HVAC project, I have an outdoor air quality sensor from Ambient Weather (no sponsorship, I bought with my own money, etc). It’s battery/solar powered, and that’s fine… except for the part where that doesn’t work here in the winter. We just don’t get enough sun or close to it.
But it plugs in to charge and keeps working when plugged in, so winner winner chicken dinner, right?
WRONG! Because to do that you have to take the bottom off the case, and then, the charge plug sticks directly out from the bottom facing down, like a goddamn Apple Magic Mouse.
So maybe I can’t fix the mouse, but I can fix this, and so I have made a printable tray and rack system that lets you use it that way without it being stupid. Enjoy!
HVAC assist system. It cut our peak electricity bill by 40% year over year under similar conditions, too, with substantially better performance.
But really it’s very simple. All I’m doing is improving the effectiveness of very traditional methods of temperature control by being more accurate and much more aggressive about exchanging air in and out when appropriate. Obviously in the middle of a 90-110F heat wave that’s not going to matter, so it’s more of a northern thing - but it really does a great deal in a lot of climates. (And in spring and autumn in more southern climates, I suppose.)
One of the key elements is that outdoor temperature varies a lot from point to point on the property, so we have air exchange measured at five points around the house, keyed to local indoor vs. local outdoor air temperature. (And air quality and a few other things, of course.) The actual air exchange is a combination of the original air-exchange system plus just opening and closing windows. We overcool at night with air exchange so we’re always below ambient outdoor temperature during the day.
It’s remarkably effective. We went from… well, it varied a lot, but +7 to +10 F above ambient to -7 to -5 below. (I was doing all this in C internally but F because I was talking about it to Americans.)
Again, I’m in an environment where this is particularly effective, but it costs so little and saves so much money and energy use I have to think it has some general utility many places.
Looks neat! Do you have more details you can share about your HVAC system? What are you measuring, what are your actors?
HVAC assist system. It cut our peak electricity bill by 40% year over year under similar conditions, too, with substantially better performance.
But really it’s very simple. All I’m doing is improving the effectiveness of very traditional methods of temperature control by being more accurate and much more aggressive about exchanging air in and out when appropriate. Obviously in the middle of a 90-110F heat wave that’s not going to matter, so it’s more of a northern thing - but it really does a great deal in a lot of climates. (And in spring and autumn in more southern climates, I suppose.)
One of the key elements is that outdoor temperature varies a lot from point to point on the property, so we have air exchange measured at five points around the house, keyed to local indoor vs. local outdoor air temperature. (And air quality and a few other things, of course.) The actual air exchange is a combination of the original air-exchange system plus just opening and closing windows. We overcool at night with air exchange so we’re always below ambient outdoor temperature during the day.
It’s remarkably effective. We went from… well, it varied a lot, but +7 to +10 F above ambient to -7 to -5 below. (I was doing all this in C internally but F because I was talking about it to Americans.)
Again, I’m in an environment where this is particularly effective, but it costs so little and saves so much money and energy use I have to think it has some general utility many places.
Here are some of my posts about it:
https://solarbird.net/blog/tag/ambient-hvac/
Wow that’s super cool! Thanks for sharing!