Is there such thing as a Z-wave "load detector" module

[moerderin@gmail.com]

First, the high-level use-case:

• When the NVR (via IP camers) detects people, turn on the front lights.

Now the complicated part:

My NVR comes with a relay module such that when it detects motion it completes the circuit and can turn on a light bulb for example. Rather than turn on a light bulb, I want some sort of Z-Wave module that detects when the load on the circuit. When it gets triggered, then I can detect it and use Homeseer to turn on all my outside light switches.

I feel like "dry contacts" or "wet contacts" maybe what I'm looking for but even after googling them I don't fully understand it and am honestly new to this space and feel like it's probably a pretty simple solution if I even knew the terminology that I should be googling. Thoughts?

[ericg]

Hi,

Your diagram indicates that your relay can be wired as "dry contact"; i.e., no power to the contacts, it's just a switch. The Z-wave module most people (in my experience) use is a battery operated door open/closed sensor. These things are as cheap as a Z-wave module gets. They ordinarily use a magnet to operate an internal switch when the door is closed. A few models have internal terminals that you can use to supply your own switched input to the module.

Although it's often possible to hack a standard unit to accept the output of your relay, IMHO it's easier to just buy a unit that already has the terminals. A model I use can be found here:

https://www.amazon.com/Z-Wave-Magnet...593088078&th=1

To use it, run one wire from your relay ground to either of the terminals inside the unit. Run the other relay wire to the other terminal inside the unit. Set the magnet aside because you won't need it.

Once you have the Z-wave module connected to your motion detection relay, you'll need to write a HomeSeer event along the lines of:

IF motion_detected becomes On
THEN set all_lights On

Good luck!

[moerderin@gmail.com]

Thanks Eric! I'll give your door sensor a try.

Another thing I was thinking of doing is buying a MIMO Lite (although it's more expensive than your option). The use I had in mind would be:

• Relay 1 -> Sig1 +
• Relay 1 Ground -> Sig1 -

Would that do essentially the same thing? or do I have my wiring wrong?

[ericg]

Thanks Eric! I'll give your door sensor a try.

Another thing I was thinking of doing is buying a MIMO Lite (although it's more expensive than your option). The use I had in mind would be:

• Relay 1 -> Sig1 +
• Relay 1 Ground -> Sig1 -

Would that do essentially the same thing? or do I have my wiring wrong?

I don't have one, but yes, the MIMO Lite would likely also meet your needs. It is, as you say, considerably more expensive. And I think you have the wiring right.

I have read that others have made good use of this unit for gate control. They use the MIMO's output to drive a gate motor, and the input to verify open/closed status.

One difference that might affect your choice: The door opener I recommended uses a single CR123A battery, while the MIMO is powered by a (supplied) wall wart. My two units have been in service for about two years, and they are both still using the original batteries.

[Roger D]

moerderin@gmail.com,

Another option is the Aeotec Door/Window Sensor 7 Pro.

It accepts a dry contact and in addition, it can also be powered remotely if you do not want to use the battery. I have several that I'm using in HS4 and they have been flawless
Note: Only the Pro version has the terminal strip to accept the remote contacts.

It's small at about 3 inches long. Here's a photo showing the insides.



The user manual is available here.




Hope this helps,

Roger D.

[Dweber85rc]

I have used the door sensors with dry contacts for things like this for years. I also have a mimolite doing the same thing and they are at least twice as expensive as the door sensors. But they don't need a battery either. If you think you might have multiple dry contact sources in that same area a raspberrypi or arduino work well for that.

[moerderin@gmail.com]

Hi,

Your diagram indicates that your relay can be wired as "dry contact"; i.e., no power to the contacts, it's just a switch. The Z-wave module most people (in my experience) use is a battery operated door open/closed sensor. These things are as cheap as a Z-wave module gets. They ordinarily use a magnet to operate an internal switch when the door is closed. A few models have internal terminals that you can use to supply your own switched input to the module.

Although it's often possible to hack a standard unit to accept the output of your relay, IMHO it's easier to just buy a unit that already has the terminals. A model I use can be found here:

https://www.amazon.com/Z-Wave-Magnet...593088078&th=1

To use it, run one wire from your relay ground to either of the terminals inside the unit. Run the other relay wire to the other terminal inside the unit. Set the magnet aside because you won't need it.

Once you have the Z-wave module connected to your motion detection relay, you'll need to write a HomeSeer event along the lines of:

IF motion_detected becomes On
THEN set all_lights On

Good luck!

Wow, this was absolutely amazing. It felt a bit like magic to be honest.

Especially appreciate your thorough "todo" instructions.

[SirCJW]

I am also just getting into this and this is great information. My question is from the routine perspective has anyone written in the logic to check If it is dark out (or integrated sunrise / sunset times) so it only turns on the lights at night. Also when the motion stops one would assume that the cameras stop recording and the relay would return to NO / NC state depending on how it is wired. Has anyone written this code to keep the lights on for a given period of time after motion stops or put them back to a prior state (lit in a non motion state). I ask because these lights may not only be motion driven but also be on for a purpose and you do not want nuisance tripping where you are working in the yard, the lights turn on at dusk or are flipped on and suddenly you move and the cameras start and the lights are now being driven by the relay and will turn off once the relay is disengaged as an example. I have wired all my outside lights so that they can be on / off / motion switch driven and return to that state even with a power failure (which generally resets and screws with the dusk to dawn / motion situation)

[ericg]

If you want the lights to come on only at night, you might use something like this:

IF motion_detected becomes On
AND IF The time is nighttime (after sunset, before sunrise)
THEN set all_lights On

Now suppose you want to turn off the lights if there has been no motion (i.e., the detection relay has been open/reset) for, say 5 minutes. An easy way to satisfy this need is to create another event similar to this:

IF motion_detected has been False for exactly 5m,0s
THEN set all_lights Off

Let's look at some implications of this second event:

• The sensor design will usually keep the relay output active for a predetermined period past the last motion detection. It may be a second or two, or it may be a minute. The event offered above will keep the lights on / cameras running for an additional 5 minutes after the motion detector resets.
• If a person or animal is lurking, that motion_detected relay will may be going on and off as the animal/person moves around. You probably don't want your lights/cameras to be tracking this on/off sequence. Once the lights are turned on by the first event, they will stay on for a full 5 minutes after the motion sensor no longer detects motion.
• If the lights have been turned on for some other reason -- perhaps you are expecting a guest -- then motion_detected will not become true until the guest arrives. The IF trigger for the second event cannot be satisfied until 5 minutes after motion_detected resets, so the lights will stay on indefinitely as the guest is awaited.
• A common mistake is to set up an event that runs continuously (i.e., once every second) when the desired condition has been satisfied. That's why the trigger for the second event above uses "exactly" instead of the "at least" option.

Now let's turn to the "working in the yard" situation. If you're working in the yard during the day, the lights won't be on, and they won't turn on. But what if you want to work in the yard at night in an area where the motion detector will notice you? So you turn on the lights with a switch before you go outside. The first event will trigger, but it turns on lights that were already on, so no harm done. And if you keep moving around as you work -- i.e., motion-detected at least once every 5 minutes, then the lights won't go off. But if you take a break or move outside the sensor range for 5 minutes, then you might very well find yourself in the dark.

One way to deal with this problem is to introduce a new virtual device. Let's call it motion_enabled. We enhance the first event:

IF motion_detected becomes On
AND IF The time is nighttime (after sunset, before sunrise)
AND IF all_lights Off
THEN set all_lights On
THEN set motion_enabled True

The second event is modified:

IF motion_detected has been False for exactly 5m,0s
AND IF motion_enabled is True
THEN set all_lights Off
THEN set motion_enabled False

If you've turned on the lights before going outside to work, then the first event can't run, and motion_enabled won't be set. You can go outside and do whatever you wish for as long as you wish; and you won't get caught in the dark, because neither event will be triggered. You can go back inside, and the lights will still stay on until you turn them off from a switch. Note that, the moment you turn off the lights with a switch, the motion sensor is enabled to turn on the lights when there is motion.
All this is from the top of my head -- I haven't done any testing. And it's possible, of course, that I misunderstand the problem. But I hope that you will find this helpful.

Edit:
If you want to control both lights and cameras, you probably don't want to lump them together. For instance, you may not want your cameras running if you just went outside to do a little night work. It should be easy to extend the system to cover this situation.

[Roger D]

You can also create a single event like so...

IF
Motion_Detector Had its value set to: On
AND IF
The time is nighttime (after sunset, before sunrise)
AND IF
Manual_Override_Switch is Off
THEN
Set Device:
Motion_Activated_Lights to: On
+
Remove Delayed Device Actions for: Motion_Activated_Lights
+
Set Device:
Motion_Activated_Lights to: Off
after a delay of 5 Minutes, 0 Seconds

This is neither the right nor wrong way of doing it. It's just a way that simplifies it for me, YMMV.

Roger D

[Roger D]

Just to throw another way of doing this out there you can use a dimmer for the lights and have them to come on at say 25% or so and when motion is detected they go to full brightness.

I do something similar with the HS-WD200+ Dimmer.
At Sunrise daily everything resets and LED_1 on the dimmer turns Blue

At Sunset daily
Lights turn on to 20% Brightness until Dawn with Motion Override. (The Default Operation)
Dimmer LED_1 now goes to Green
If Motion is detected during this time then LED_1 blinks red until motion is no longer detected

A single Tap up on the switch overrides normal operation and the lights go to 100% on with Motion disabled, LED_1 turns solid red.
A Double Tap Up turns off the 20% and only uses the Motion activated lighting. LED_2 turns purple.

A single Tap Dwn returns the system to the default 20% w/Override
A Double Tap Dwn Turns the lights off till the morning

At Sunrise everything goes back to defaults.

This is just one way of doing things, you can get carried away quickly if you aren't careful.

Roger D.