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I have a water pump at my home that I want to connect to 12 switches, so that each one of them can turn the water-pump on/off. Can it be done?

Thank you!

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    I'd love to hear your use case for this, as well as why you want "alternatives" to 4-way switches. – isherwood Feb 2 '16 at 17:24
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    It's perfectly reasonable to want alternatives to 4-way switches. They are not that awesome. They don't indicate position. They require high voltage in every location... and flowing operating current a long distance and through many connections (46?). They won't work with high current loads. With this many control points, other stuff starts to make sense. – Harper - Reinstate Monica Feb 2 '16 at 17:52
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    I suspect (reading between the lines) that this is a home in need of a powered potable water system and has 12 locations (baths, laundrys, faucets, etc) that need to be able to turn it on when water is needed and off when not in use. If this is the case then I suspect a more appropriate description is that you don't actually need to turn it on OR off from any point, you need to be able to turn it ON from any point (the difference is important and impacts the answer to the question) i.e. do you want to allow for multiple users to have it "on" for their duration and not interrupt other users. – Jeff Meden Feb 2 '16 at 20:32
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    I have no experience with this application, but if OP wants to turn on a pump from any of 12 locations, isn't there some sort of water pressure sensor that will turn on the pump whenever a spigot is opened? – JS. Feb 3 '16 at 0:02
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    @rtecxs can your tank be operated by a float switch? – Brad Feb 3 '16 at 3:58
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Yes, the first switch in the circuit from the panel would be a three-way switch. The last switch in the circuit before the pump would also be a three-way switch. Then the other 10 switches would all be four-way switches.

Four way switch diagram

Multiple four way switch wiring

  • So, if suppose i switched on the pump from switch no. 1 then will i be able to switch off the pump from say switch no. 5? – rtecxs Feb 2 '16 at 17:07
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    Yes. It might be educational for you to look at the circuit and figure out why. – keshlam Feb 2 '16 at 17:09
  • Are there any alternatives to 3 way or 4 way switches? – rtecxs Feb 2 '16 at 17:16
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    @rtecxs 3-way and 4-way switches are cheap, effective, and will do what you're requesting. I'm not sure why an alternative would be necessary, but.. to prevent making things complicated - this would be what you want. No reason to reinvent the wheel. – TFK Feb 2 '16 at 17:18
  • @rtecxs Sure! Have a bunch of smart switches that route to a home intelligence system, which runs arbitrary code based off of their state, and switches the target device on and off. All of the functionality, 10 to 100 times the price! – Yakk Feb 3 '16 at 15:43
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Yes, you use 4-way switches. Here is an animation that shows how they work. You can have as many 4-way switches as you want, in the middle. http://users.wfu.edu/matthews/misc/switches/4WayAnimation.html

Changing the switch causes the pump to change. If it was on, it will be off, or vice versa. The switch position will not tell the user whether it's on or off. If you want that, use switches with a "pilot light" feature.

EDIT: Folding some of my additional comments into my answer.

There are many "smart switches" on the market that can do a lot of things. You may be able to adapt these easily. Some of them even use wireless controls for extra switches, so you don’t have to run wires everywhere.

You could also use pushbuttons (so the pump only runs when a person presses a button). Either the pushbuttons would have to handle a LOT of current… or they could switch a small DC voltage (12 or 24 volts) which would then operate a relay to power the pump. The power would come from a small transformer at the pump. Even better, use a time-delay relay, which will continue running the pump for a set amount of time, so you don’t have to keep holding the button e.g. while the toilet refills. Edit: Here's an example of a low-voltage system. I only show 2 pushbuttons here, add as many as you want. Code-legal versions of these parts are common. Single-pushbutton relay controls

A more sophisticated method is commonly used in industry. Each location has TWO pushbuttons, an "on" and "off". There is a latching relay at the pump. If someone presses "on" anywhere, the relay switches and stays on. Push the other, it switches and stays off. You'd need at least 3 wires, but they can be thin wires. You can’t see the pump status unless you add a pilot light (4th wire). But you don’t really need to - if you simply press “off”, it’s definitely off. Edit: Here's an example of a latching relay circuit with 2 push buttons - note the optional "power relay" in case a latching relay isn't strong enough, and also the optional indicator light circuit. enter image description here Edit: There's a variant on a latching relay called an impulse sequencing relay. It only requires one pushbutton, not two, so you don't need the circuit labeled "O". Every time you press it, it will toggle the relay between on and off. But it will not indicate on or off, so you might want that indicator light circuit.

Lastly, if you want something really intelligent, you can feed buttons or switches to an Arduino or Raspberry Pi controller and program it to respond as you wish.

  • Are there any alternatives to 3 way or 4 way switches? – rtecxs Feb 2 '16 at 17:16
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    Sure, there is a variety of "smart switches" on the market that can do lots of things. You could also use pushbuttons (only run when someone presses a button) or use time delay relays so it'll run for some time after the button is released. If you want something really intelligent, you can feed buttons or switches to an Arduino controller and program it to respond as you wish. – Harper - Reinstate Monica Feb 2 '16 at 17:26
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    Or you could wire 12 plain switches in parallel, the pump will run if ANY switch is on, and the switch will indicate. However if anyone leaves a switch on, you'll have to check 12 places to find it. – Harper - Reinstate Monica Feb 2 '16 at 17:28
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    Another method is commonly used in industry. Each location has TWO pushbuttons, an "on" and "off". There is a latching relay at the pump. If someone presses "on" anywhere, the relay switches on and latches (stays) on. If they push "off" anywhere, the relay turns off. All ”on" buttons are wired in parallel, as are all "off" buttons. You'd need at least 3 wires, but they can be thin wires. This would not indicate pump status unless you add a pilot light (4th wire). – Harper - Reinstate Monica Feb 2 '16 at 17:41
  • @WolfHarper or a single push button at each location which triggers the relay so it switches to the inverse of the current setting. My grandparent's flat hat that for lights (though not 12 ones, just three or four). – Paŭlo Ebermann Feb 2 '16 at 20:30
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This is commonly used in industrial controls:

schematic

I've drawn it as a ladder diagram because I think it's easier to see the individual circuits and the interactions between them. You can translate from that to the actual wiring.

I'm using a second relay contact to power the load so that the control circuit only has to handle the relay, which is almost nothing in most cases. You can also add a light in each panel as Wolf mentioned, wired in parallel with the load or with the relay; which one is up to you, but consider how it might fail.

For safety:

  • All start buttons should be recessed and all stop buttons protruding. This allows someone to swat the panel in a panic stop situation but requires them to intentionally start it.
  • All stop buttons must interrupt power. This makes the pump stop immediately if a wire comes loose instead of being impossible to stop from that location. You really don't want to discover that in an emergency.
  • You might also consider using double contacts for the stop buttons and for the relay contact that powers the load. Make sure that if one decides to weld itself, the other can still operate, and wire them in series. Also consider how you might detect a welded contact for mandatory replacement.
  • 1
    To add a schematic to any SE site: 1) Start a question on a site that has a schematic editor. This includes Electronics, Raspberry Pi, and maybe some others. 2) Draw and insert the schematic as usual. 3) Copy the generated markup into where you actually want it. 4) Discard the original question. – AaronD Feb 2 '16 at 19:51
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    No. That is not what I'm talking about. I refer to a commercial device made for code electrical work, called a latching relay. Google it. – Harper - Reinstate Monica Feb 2 '16 at 23:19
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    @WolfHarper I've never actually seen one of those used, nor did I see what you described in a casual google search. If I understand correctly though, it sounds like a safety hazard to me because a loose or broken wire could make it impossible to turn the pump off remotely. That's if you're serious about all the "off" buttons being wired in parallel; I thought it was a typo. – AaronD Feb 3 '16 at 3:19
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    Try mouser.com/ds/2/357/105A_755-7090.pdf ... I'm glad for your enthusiasm about safety, but blind overdesign and condescension don't lead to actual safety. I've seen it tried by novices, it ironically leads to unsafe practice. Ultimately safety of a particular application depends on its failure tree (worst case scenario), and the designer knows that. Leave it to him. – Harper - Reinstate Monica Feb 3 '16 at 5:23
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    Keeps adding information? Then why haven't I seen...oh, it's in the disorganized comments that SE hides by default! Hey @rtecxs, could you please edit ALL the relevant details into your question itself so that everyone can see it? Thanks! – AaronD Feb 4 '16 at 2:12
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For that many locations, I'd strongly consider one of the types of switches intended for home automation applications. One switch would actually control the pump, and the others would signal that switch to turn on or off. Some of them offer battery operated remotes that can be used without any permanent wiring, or you can mount a switch in a normal junction box as long as you have a neutral and hot wire available.

Check into Insteon, Lutron, and Z-wave switches.

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maybe I'm missing the issue, but it would seem a lot simpler and possibly cheaper to just install a small pressure tank controlled by a single pressure switch to the incoming water line.

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