Weatherproof "button"
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From: Sjouke Burry on 4 May 2010 18:40 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 > > 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) You just described a waterpump used in boats an caravans/mobile homes, to put pressure on the watertap. It senses pressure and activates, when pressure is low. I dont find them very reliable however.
From: D Yuniskis on 4 May 2010 19:09 Hi Sjouke, Sjouke Burry 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". > > 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. This has promise -- see below. > 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). Switch would then have to be "movable" (tiltable) -- which poses yet another problem. > 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. This would be cool! But, the tubing would probably die in the constant sun exposure. > 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. Big. Not "unobtrusive". But, solution 1 -- taken in concert with garden gnome, "magnet on a string", etc. can work. Except, turn it around: *fix* the sensor (reed switch, hall effect, etc.) and let the magnet (passive) be the moving member (like the magnet in the gnome's feet or "magnet on a string"). Pot the sensor in RTV, recess it into the wall, paint over it. I.e., good and weatherproof. Very unobtrusive. Now, let magnet either take the form of the movable portion of a "door knocker" *or* a "pendulum" SUCH THAT the rest position engages the magnetic sensor. To "activate" the switch, you lift (door knocker) or nudge/twist (pendulum) the movable magnet so that it momentarily breaks the magnetic circuit. Expect gravity to (eventually) return the magnet to its "resting place". I.e., "magnet on a string" but without the string (or, perhaps I misinterpreted Lasse's post?). *And* "normally closed" instead of "normally open" (in the semantic sense). I think this should work as all of the sensitive parts are "potted"/protected. And, it can be dressed up so that it doesn't look like a "switch" (hmmm... a garden gnome walking up the wall?? :>) Thanks!
From: D Yuniskis on 4 May 2010 19:11 Sjouke Burry wrote: > 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 >> >> 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) > You just described a waterpump used in boats an caravans/mobile homes, > to put pressure on the watertap. > It senses pressure and activates, when pressure is low. > I dont find them very reliable however. It wouldn't work in this application. First, it has to be able to work when the manual "faucet" has been left open (and the electric valve has since turned off) -- so, no water pressure to sense (unless you deliberately let the electric valve "leak" :< ). Second, it won't work when the master (water) valve has been turned off -- *no* pressure anywhere in the supply line. As I said, it was an amusing idea but it wasn't practical.
From: Robert Baer on 5 May 2010 00:24 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... :< Well, do not toss out the magnetic approach - but use a reed (relay) switch and positioned "chunks" of iron to "hold" the magnet in all positions.
From: JosephKK on 5 May 2010 06:23
On Tue, 04 May 2010 14:50:12 -0700, D Yuniskis <not.going.to.be(a)seen.com> wrote: >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. I have seen water timers that you place inline with your hose, it gives you a set amount of time (adjustable) and stops the flow. You have to disconnect it (pressure lock) to use it again. No batteries either. |