Weatherproof "button"
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From: D Yuniskis on 4 May 2010 17:05 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... :<
From: Joerg on 4 May 2010 17:09 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... :< Where is it mounted? Side of a shed? House? On a pole? -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: langwadt on 4 May 2010 17:10 On 4 Maj, 23:05, D Yuniskis <not.going.to...(a)seen.com> 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... :< use a reed relay and hang a magnet next to it in a piece of string? :p -Lasse -Lasse
From: Ecnerwal on 4 May 2010 17:33 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. 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? Beware the effect of lightning on your exterior wires, and things they attach to inside... -- Cats, coffee, chocolate...vices to live by
From: D Yuniskis on 4 May 2010 17:39
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! :> |