Hello I have two ceiling fans are are in the attic venting out hot air. I want to send when they come on or off. they have some kind of temperature sensing device that let's them know when there is to much heat and it comes on and goes off when it gets cooler. Now Only thing i can think of is some kind of current sensor sensing If there is some kind of current to the fan when it comes on. I have not open the boxes up to see what is inside. But i thought i get a opinion or two and see if i can't attach something inside what would be the best back for outside wiring detecting.
Please follow up with the rest of your plan. It may have a bearing on how you sense the on/off.
Are there louvers on the outside of the vent? Are they hinged so the fan blows them open? Is there an second vent that allows cool air in when the fan runs? Does it have power opening louvers?
How do you want to be notified of the fan status? Will you use wires from the fan to somewhere else? Will you have to put in some power supply in the attic to operate the sensor and send the status?
Hello the vent is completely open no louvers or hinged at all. I tried to go up there but it feels like almost 200 degrees in the craw space attic. Even though it's only 88 degrees outside. There are small boxes attached to the wiring and sounds like relays in it. So I'm going tomorrow up there to open one up before the sun comes up and fans turn on.
But i came across a post from year or two ago some guy was doing the same thing and one thing someone came up with the idea of taking a cellphone charger which inputs 110v and outputs 5v to use that 5v for detection to the arduino. Now I'm good with working on 110v. I have done a lot of power wiring and breaker replacements in the past. I can rig something like that up. then I was thinking of maybe using a 433Mhz transmitter, Receiver.
Wonder if that be better this way instead of messing with that control box and whatever inside of it? Also i'll still take pictures when i go up there tomorrow.
Hello no they are tied into a breaker that the lights and some outlets are on the same circuit. there are a total of 4 fans they look to be about 12 inches maybe a little bigger and from the Power coming into a box. I saw one of them have a Temperature adjuster you can see the Degrees on it and then from that box goes out to the fans.
Guessing again! The fans all have a screen on the outside to keep the two, four and 6 legged creatures out of the attic.
I would investigate a heating duct air movement sensor and find a way to attach it to the outside of one screen. The sensor has a sail attached to a microswitch. Air pressure moves the sail and that opens/closes a switch. Then there is no reason to work with the power wiring.
Oh I'm sorry i forgot to say they are sticking out side of the roof not the side of the house. they have a round cap on top with a mesh wiring screen yes. I was getting ahead of my self. My my apologies.
I will do some more looking into the box tomorrow and take a few pictures of what is inside.
Saw a non-contact simple arrangement the other day which would suit.
Used 3 transistors.
See if I can find it again and drop a link here.
I see this kind of thing asked many times before.
josephchrzempiec:
Now Only thing i can think of is some kind of current sensor sensing If there is some kind of current to the fan when it comes on
You think right, one part, and probably no need to look inside the box either. The only thing left to think about is whether you can/want to break into the cable. If that's OK, $3, or use a non-invasive clip-round ring, about $9.
If you just want to know when they are on, put a little neon bulb on the hot side of the fan's motor to common. It'll come on when the fan turns on and extinguish when it stops. It'll cost you thirty five cents and about an hour all told.
You might try using a vibration sensor module. About $2 US or less from China. High state pin if still and Low state pin if vibrating. Suspect these fans might vibrate enough to trigger the sensor.
Hello Thank you all for the input. I'm still undecided on what to do or use yet. But In 24 hours i will upload a new update on what i would like to do and how i do it. Again Thanks everyone for the help and Pointing me in the right direction.
wzaggle:
You might try using a vibration sensor module. About $2 US or less from China. High state pin if still and Low state pin if vibrating. Suspect these fans might vibrate enough to trigger the sensor.
Wzaggle Now that is a idea. That might be doable. Thank you. I will add that into the list of parts that might work.
wzaggle:
You might try using a vibration sensor module. About $2 US or less from China. High state pin if still and Low state pin if vibrating. Suspect these fans might vibrate enough to trigger the sensor.
I love this idea. Adafruit also sells vibration sensor switches for about a buck a pop.
Another idea! Put a neodymium magnet on a fan blade that trips a reed switch when the magnet rotates past.
jrodda:
I love this idea. Adafruit also sells vibration sensor switches for about a buck a pop.
Another idea! Put a neodymium magnet on a fan blade that trips a reed switch when the magnet rotates past.
If the vibration sensor didn’t work, just attach the magnet (or any weight) as mentioned and the vibration sensor idea would absolutely work. That is until the fan shook itself to pieces from the out of balance blade.
I wish the OP would decide where and how he wants to be notified that the fans are running. Once he wants a minimum of components and next he suggest an RF link from the attic to ?
