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120Vac Timer which is like a three-way Wall switch

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MikeMl

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I'm finishing the wiring on my new house, and have encountered a county code issue. The county has a "dark skies"policy, where external house/yard lighting is either limited to max lumens, or the external lights must turn off automatically within ~10min after being turned on. The lights in question are controlled by a " (US) four-way" circuit (three switches), where the power feed is to one end of the string of switches, and the far end switch feeds the lights, just like this:

**broken link removed**.

The existing switch at the load end has a normal (Com, NO, NC) form C switch with power fed to it only on the travelers and it has Neutral available.

I need a "three-way switch/timer" (White, Decora) that is just like the normal "three-way" switch it replaces, except that it should automatically reverse the feed to the load from the "travelers" 10min after any switch in the string was last operated. Note that this requires the timed switch to be triggered either if the local handle is manually operated, or if any of the upstream remote switches causes a reversal of which traveler is hot.

I am either looking for a ready-made solution, or if necessary I will build my own circuit.
 
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I think changing the switches it the wrong thing to do.
I think changing the light (or near the light) is better.
I think there are timers that will count to 10 minutes and turn off. So any time power is sent to the light it will turn off in 10 minutes. To turn the light back on it will require you to turn off, then on the light. (flick the switch twice)

I have relays that work like that. There might be a electrical (not mechanical) bath room fan timer like that.
 
What is the nomenclature for an 120V AC-powered timer module that turns on its load when power is first applied, keeps the load turned on during the timing interval, and then turns off the load even though power remains applied to the timer.
 
Boy, that sounds like a really tough problem.

I suspect,, though, it can be done with an Insteon system. Expensive though.

With the contacts being maintained, it might be tough.

Although a Delay-On-make module at the light does offer a solution. Flipping the state once it turned off would require a toggle operation at any switch. That's the only drawback. So if off, the first flip would do nothing. The second flip would turn it on IFF it turned off via the timer. If it did not, then a flip would change the state.

So, I guess you can say that if the light is off you may require a toggle with at least a 0.050-0.1 second pause between each flip.

I know Insteon has been used to turn off a bathroom fan, That system is EXPENSIVE.

Check out www.ssac.com Watch lights being inductive (CFL's) when you select the module.

Now, i do have another better idea:
Create an electronic DPDT switch just as the traveler is. Make this a alternating latching relay or impulse relay. Tough to find. when the light turns on, start timing. After the 10 min interval, pulse the electronic switch. So, you need a delay on make (10 min) and a delay on release (100 mS pulse) The DPDT is used for the n-way switch.

see: https://www.electro-tech-online.com/custompdfs/2012/09/711_Series.pdf
and www.ssac.com

I need to apologize for the unconventional thinking. I tend to start someplace and modify. Even if the idea is unworkable or creepy. So, I came up with three different ways.

A fourth would be a custom solution, say using a PICAXE to implement the timer. It's probably possible that the system could go to sleep totally when the lamp is off.

Figuring out how the mounting and logistics of the system goes together is difficult in itself.
 
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You might try using a "ratchet relay". They are relays that have a alternate action mechanism to change the contact state from one position to the other each time the coil is pulsed.

Put an SPDT version in place of the switch at the load end of the switch string. Put a small power supply in parallel with the light. When the supply powers up, it starts a timer. After 10 minutes, the relay coil is energized, 'flipping' the switch to the other position. This turns off the light and the power supply until another switch changes position.

Typo correction.
 
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Chris: How is that going to work? Your "Ratchet relay" is my impulse relay with a datasheet to match. Why the extra power supply?
I pretty much had it covered.

As pictured, in the OP's schematic a "FAKE" DPDT switch or "DPDT impulse relay" is inserted into the n-way switching arrangement. Now, the only thing that has to happen is that after the 10 min timing interval, a pulse is generated to change the state of the "Impulse relay".

All you need is a mechanism that when 120 VAC is supplied, it waits 10 minutes and supplies a pulse > about 50 mS. It's possible to not use any extra power supplies and no power is drawn when the lamp is off.

This timer, https://www.electro-tech-online.com/custompdfs/2012/09/k141-1.pdf would require a DC supply. Mode 7, a recycling timer would actually work, so a 120 V recycling timer could also work.
As another example: http://www.ics-timers.com/op45_46.html

The timer would never recycle. It would time the first event, and then turn itself off indirectly, so it won't recycle, but it will work.

Let's think about what happens if power failed (Won't consider between states). If the light is off, no problem. If the light happens to be on, it will stay on and then go off in 10 minutes.

If it was timing in the 10 minute time frame, no big deal. Glitches would, in theory, be possible if power failed during the 1 second pulsing. I think in this case, being a recycling timer will fix any glitches. I might guess that 20 minutes on is a remote possibility.

This would be OFF for 10 minutes and on for 1 sec or so when power is first applied. See, basically two standard parts, but rather large and it APPEARS that the parts have to be installed in two locations or at a minimum two cables from two locations into a single box.
 
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There is a time relay in my garage door opener for turning on the light.

"Interval on time delay relay:The relay energizes and timing begins when input voltage is applied. At the end of the time delay period the relay will de-energize. Reset is accomplished by removing, then reapplying, the input voltage."
From Tyco See CH series relay. See CB series.

On the S-timer data sheet drop down to the third page.
 
The latter isn't too bad at all. The wattage wasn't specified, nor the type of lighting. Low voltage lawn lighting could likely cause some issues.


I didn't realize that you were wiring a new house. In that case you have options that some won't have. If you use UL listed components then I doubt I'd see any problems with the inspectors. Anything that has connections needs to be accessible. If we are talking some space in an unfinished basement, then a J-box or better yet a -box with a 1/4" aluminum panel in the bottom attached via a spacer, could house the two components. If you want to do something super exceptional use DIN rail and terminal blocks to make the connections. It's just two parts.

Here is a better pic http://www.electrical-online.com/wp-content/uploads/2010/09/4-way-network-simplest-method.jpg to illustrate what has to happen.
1. The middle DPDT switch is the impulse relay.
2. The Last SPDT switch needs a 3 conductor cable to your "control box"; just switch to control box.
3. The First switch (output side) goes to your "control box"
4. And you need a two conductor output.

If I had my druthers, I's probably get a wall flange mountable control box and make power enter it. Go to a DIN rail mounted breaker and wire to the first switch. terminal to terminal. Do the same for the last switch (terminal to terminal) and have an output.

Then internally, I'd create a DIN terminal and spacers between each set. (2)(end plate)(ground terminal)(3)(end plate)(ground terminal)(3)(end plate)(ground terminal)(2)(end plate)(ground terminal

You then just wire the cables to the appropriate terminals. Power in/switch/switch/power out
Mount a DIN rail breaker to satisfy a disconnect within 3 feet.
Mount the impulse relay using a DIN rail socket
Mount the other relay using a DIN relay.
Although not strictly necessary, you COULD fuse the timer output.

This then becomes a nice easy to troubleshoot control system. Been there. Done that.

If this really is lighting and later you wanted to add some sort of remote control like from your cell phone etc, it might be wise to make the box larger.

Going say the insteon route, you might need a module that can deliver a pulse and an AC presence signal conditioning. You may also need a DIN moutable wall outlet for the Insteon device.

AC power module: http://www.asi-ez.com/member/x124-AC-Power-Module-DIN-Rail-Mount.asp

Here is a GFCI DIN breaker, but you can get regular ones too: http://www.asi-ez.com/member/x557-Ground-Fault-Protectors.asp

Here are some terminal blocks, but the quantity minimums are too high: http://www.asi-ez.com/member/x526-Terminal-Blocks.asp

Here is some T-35 rail: http://www.asi-ez.com/member/x046-DIN-Rail-Cutter.asp

L-comm primarily sells waterproof enclosures http://www.l-com.com/item.aspx?id=29808, but it gives you an idea. These have the backing plate and they even have a duplex outlet inside.

Here is a fancy NEMA-1 enclosure and the sub-panels are optional: http://www.automationdirect.com/adc...s/Metal/NEMA_1/Single_Door_Wall_Mount#listing Yep, big and expensive.

These are just ideas. Something to make the wiring pass and look neat.
 
Sorry for being slightly off topic but I'm stunned that people are not allowed to decide how much light they want in their own backyards! What if someone is working outside at night? Or wants to light up their yard for a party, or to deter intruders?

I'm wondering how well that "law" would stand up in court. "ive never heard of someones "right to light" being taken away before and it sounds very disturbing!
 
A neighbor had to install awnings because a neighbor of ours likes to light up his back yard and in his case his bedroom. The light would be on nearly all night and they were floods.

Then again, neighbors at the top of the hill petitioned the power company to install a street light. They wanted everyone on the street to pay first, but those a few doors away would have no benefit.

Courtesy makes some sense. if there is no law, you can't enforce it. You can't enforce "common courtesy" like don't mow your lawn at 5 am in the morning.
 
As usual, I've been thinking again: See **broken link removed**

I don;t quite understand the instructions, but it looks like it could become the basis of what you need.

A lot of the Insteon stuff requires a neutral in the switch box. If I were wiring a house I'd use 3 conductor with ground from the light to the switch in every room. This opens up a lot of automation options. The light would have power (2 wire) and the switch (3 wires) would have hot, neutral and a switched hot and thus you have options.

However, central lighting systems could even be better where the lights are run to a central location. The switches are part of an automation system. Ceiling fans are common too. Speed control of ceiling fans is tempermental at best.
 
Roman,

I just moved to rural northern Arizona. I am blown away by being able to go outside at night and being able to see billions of stars, including the milky way, right out the back door. I just moved from a large industrial city, where the only thing you see looking up is the sun, moon and about a half dozen planets and stars.

The limitation on what you can see down here is that one neighbor about a 1/4mi to the east insists on leaving the porch light (~60W incandescent) on all night; another, about a mile to the north has a 500W halogen yard light. Those two lights are so bright as to screw up my view of the night sky...

The county dark skies ordinance stems from an initiative to protect the Lowell Observatory. I'm good with the requirement that outside lights not be left on all night. Unfortunately, the ordinance grandfathered stupid people with preexisting houses, so only new construction is subject to the timer/lumen requirement...

I'm all for individual liberties, but there is always some yahoo that thinks their right to personal freedoms trumps what might be the greater good...
 
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...See **broken link removed**

I don;t quite understand the instructions, but it looks like it could become the basis of what you need....

I looked at that before I posted. I cant figure out how to trigger a new interval by using the existing external switch(s). It appears that I would have to install the time switch at the load end of the four-way circuit. I can see what they are doing with just one extra switch, but cant figure out if there are enough wires from switch to switch to trigger a new cycle from multiple other places.
 
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You had to make me look again, didn't ya?

Look for "Vzia". I found this: **broken link removed** It doesn't have enough wires because the device is Z-wave.

I can see how a 3-way switch is wired, but they do mention n-way but it doesn't seem to be discussed. As expected the first switch gets a line and a neutral and the timer/switch has to control the load and it also gets aline and a neutral. This, then looks different than the typical power at the light fixture and the switch runs to the light fixture.

I hate wires where the functionality isn't defined. Leviton has a habit of doing that. Some sort of block diagram would help. Who knows what the functionality of the wire between the devices? W hat happens when you add another to try to make it n-way? It could very well be an indicator feedback signal.

The instruction sheet here: **broken link removed** does actually call a terminal "Remote", but it still seems very vague. Leviton, AT&T and Verizon belong in the same box together.

Note that there is a support number.

Also note here; **broken link removed**

That instructions in general are barely usable for Leviton devices. That was the impression I got from looking at nearly all of their stuff.
 
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...
The county dark skies ordinance stems from an initiative to protect the Lowell Observatory. I'm good with the requirement that outside lights not be left on all night. Unfortunately, the ordinance grandfathered stupid people with preexisting houses, so only new construction is subject to the timer/lumen requirement...
...

Thnaks for explaining and I apologise for the slight off-topic intrusion into your thread. Observatories are pretty cool. :)

I suppose I could just use infra-red floods and night vision goggles when mowing the lawn at 3AM. ;)
 
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