Weatherproof "button"
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From: D Yuniskis on 4 May 2010 17:50 Ecnerwal wrote: > In article <hrq1s1$ve1$1(a)speranza.aioe.org>, > D Yuniskis <not.going.to.be(a)seen.com> wrote: > >> I need some sort of "button" (sensor?) that I can locate out >> "in the elements" and use to activate the irrigation system. >> I.e., "push this button to turn on the water supply". > .... >> Are there any other clever approaches that might work? >> Even "weatherproof" switches fail one or more of the >> above criteria... :< > > Garden gnome (or similar easily ignored as decor item - frog, turtle, > rock, gazing ball, sundial) with a magnet in its foot/base. Sealed > weatherproof box with reed switch (or Hall effect if you want to > complicate things). Offset the magnet and the switch so that when the > gnome faces one way, the switch is off, and when the gnome faces the > other way, the switch is on. The box is under the gnome. Ha! This would really be neat! But, adding something like a painted little elf to the landscaping would be kinda tacky. :< > Not sure why you want to put the switch out in the yard - most places > get by fine with said switch being in the house, and then the local > kiddies can't discover the fascinating effect of turning your gnome, and > it does not need to be weatherproof. Is walking into the house/garage > when the lawn needs water really all that difficult/time consuming? Watering the "yard" (xeriscape) isn't a problem. The rest of the irrigation system handles that. What I am looking for is something to supply water *to* the individual hose bibs (3 of them) located around the yard (independantly). E.g., there are times when I may need supplemental irrigation in a particular *spot* (like just after planting a tree; or, if it is unusually dry/windy and the roses need more water (without also watering everything *else* on the "rose circuit"). So, I want to be able to run a hose to the spot in question, connect it to a bib, open the (manual) valve to the desired flow rate and then "turn on the electrically operated valves" to cause water to be made available *to* that hose bib. Then, the controller can turn the water off some time later (without me having to go outside and close the manual valve). I.e., this sort of configuration (hose feeding some portion of the yard) might persist for several days at a time depending on weather conditions. Likewise, I might be outside and just want to "turn the hose on" to wash some dirt off my hands. I'd be annoyed if I had to "walk into the house/garage" just to get a splash of water from the hose. > Beware the effect of lightning on your exterior wires, and things they > attach to inside... Yup.
From: Joerg on 4 May 2010 17:49 D Yuniskis wrote: > Hi Joerg, > > Joerg wrote: >> D Yuniskis wrote: >>> I need some sort of "button" (sensor?) that I can locate out >>> "in the elements" and use to activate the irrigation system. >>> I.e., "push this button to turn on the water supply". >>> >>> Ideally, the thing will be cosmetically unassuming so you >>> don't notice it unless you go *looking* for it (despite the >>> fact that it will be "in plain sight"). >> >> Where is it mounted? Side of a shed? House? On a pole? > > *In* a "block" wall. (sort of like cinder blocks -- only > different! :> ) I.e., I want it to be unobtrusive. Mount > it just above the hose bib so it's right there where you *want* > it (need it) yet doesn't look like, e.g., a weatherproof > electrical box tacked on the wall. (conceptually, think of > it in the same sense as a "doorbell" -- there, yet not noticed > until you need it) > > A friend had suggested the *cleverest* approach: using the > valve on the hose bib itself (!) by sensing pressure drop > on the supply side of the valve. But, that only works when > you know the valve will be returned to the "closed" state > after use. (too bad as it would have been an engineering > delight -- using a sensor to control an electrically > operated valve to make a *mechanically* operated valve behave > as it would WITHOUT ALL THIS CRUFT! :> Well, then just mount an electical box, put an ordinary switch in it that just looks like a switch but does nothing. For camouflage. Mount a thread cap into the lower port but inside out so there's a little recess. Drill a hole and mount a wee push button in it. Nobody will see if but the people "in the know" will know that you must reach underneath and push. Any sort of proximity switch will have the issue that animals, hail, et cetera can trigger it. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: D Yuniskis on 4 May 2010 18:17 Hi Joerg, Joerg wrote: > D Yuniskis wrote: >>>> I need some sort of "button" (sensor?) that I can locate out >>>> "in the elements" and use to activate the irrigation system. >>>> I.e., "push this button to turn on the water supply". >>>> >>>> Ideally, the thing will be cosmetically unassuming so you >>>> don't notice it unless you go *looking* for it (despite the >>>> fact that it will be "in plain sight"). >>> >>> Where is it mounted? Side of a shed? House? On a pole? >> >> *In* a "block" wall. (sort of like cinder blocks -- only >> different! :> ) I.e., I want it to be unobtrusive. Mount >> it just above the hose bib so it's right there where you *want* >> it (need it) yet doesn't look like, e.g., a weatherproof >> electrical box tacked on the wall. (conceptually, think of >> it in the same sense as a "doorbell" -- there, yet not noticed >> until you need it) >> >> A friend had suggested the *cleverest* approach: using the >> valve on the hose bib itself (!) by sensing pressure drop >> on the supply side of the valve. But, that only works when >> you know the valve will be returned to the "closed" state >> after use. (too bad as it would have been an engineering >> delight -- using a sensor to control an electrically >> operated valve to make a *mechanically* operated valve behave >> as it would WITHOUT ALL THIS CRUFT! :> > > Well, then just mount an electical box, put an ordinary switch in it > that just looks like a switch but does nothing. For camouflage. Mount a Mounting an electrical box conflicts with goal of being unobtrusive. :> > thread cap into the lower port but inside out so there's a little > recess. Drill a hole and mount a wee push button in it. Nobody will see > if but the people "in the know" will know that you must reach underneath > and push. Ah, sorry, I didn't mean to suggest that this needs to be a "secret". No one has access to the yard so I don't have to protect against water thieves :> I just want it to be "readily accessible" to someone who was intent on *using* a hose, there. (hence the amusing appeal of sensing water pressure to determine when to turn the valve on -- no additional "switches" that the user would have to contend with) > Any sort of proximity switch will have the issue that animals, hail, et > cetera can trigger it. Yes. I had thought about something optical but it would then have to have its sensing target sufficiently far from the wall surface to prevent snow and ice from interfering. A little "doorbell (button)" above the bib seems the most intuitive and unobtrusive. But, finding a way to implement that which will tolerate exposure to the elements is the trick.
From: Sjouke Burry on 4 May 2010 18:26 D Yuniskis wrote: > Hi, > > I need some sort of "button" (sensor?) that I can locate out > "in the elements" and use to activate the irrigation system. > I.e., "push this button to turn on the water supply". > > It need not be a traditional "button" (in the electrical sense). > E.g., a pressure sensitive pneumatic switch, a photoreflective > sensor, etc. would all provide the intended function. The > trick is finding something that will operate reliably and for > many years when exposed to sun, rain, ice, etc. > > Ideally, the thing will be cosmetically unassuming so you > don't notice it unless you go *looking* for it (despite the > fact that it will be "in plain sight"). > > And, it should be operable without requiring anything other > than the typical parts of the human anatomy. :> > > My first thought was a traditional pushbutton in a flexible > rubber hood. But, I suspect the Sun will eat the hell out > of the plasticizers in the "rubber" in short order. > > I then thought of a magnet sliding in a channel passing a > Hall effect device (i.e., put a spring behind the magnet). > But, you'd need something (flexible) to keep the magnet > "sled" from falling out of its channel, etc. > > Are there any other clever approaches that might work? > Even "weatherproof" switches fail one or more of the > above criteria... : Solution one, use a reed relay in a plastic tube, then fill the tube with epoxy, making a 100% seal. put a magnet closeby, when you bend away the tube from the magnet, the switch reacts. Solution 2:Get hold of a mercury wetted switch, also seal with epoxy, and when you tilt that one, it switches(can stand high current). solution 3:Get a water level sensor from an old washing machine, connect a piece of rubbertube to it, when you squeeze the tube, the sensor will switch. Solution 4:any sturdy plastic box, put an industrial quality microswith inside, with the stud touching the centre of the largest area side, and seal the box well. Pressing the box will work the microswitch.
From: Joerg on 4 May 2010 18:30
D Yuniskis wrote: [...] > A little "doorbell (button)" above the bib seems the most > intuitive and unobtrusive. But, finding a way to implement > that which will tolerate exposure to the elements is the trick. You can get weatherproof ones with a high WAF factor but they are expensive: http://www.lumens.com/Doorbell-O-Button-by-HouseArt/uu107572/product?ad_id=cj&key_id=Doorbell%22O%22ButtonbyHouseArt&utm_source=cj&utm_medium=cpc Besides your friend's idea of a pressure switch which would need to be plumbed in there's also the nerd solution: Affix a piezo sensor to the line close to the hose bib, build a circuit that extracts the "psssshhhhhh" spectrum from the water when someone turns it on and let that do the triggering. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM. |