Eric Ryherd Presenting “IoT Device Testing Best Practices” at Z-Wave Summit in Oklahoma City September 26-28, 2017

Z-Wave Developers and Marketers will come together at the Z-Wave Summit at the Jasco facility in Oklahoma City September 26-28, 2017. You have to be a member of the Z-Wave Alliance to attend. I highly recommend attending if you are developing Z-Wave devices . Networking with other Z-Wave developers and having intimate access to the Sigma Design and Alliance engineers and marketing folks is invaluable. To attend, register via the Alliance member-only web site. The Alliance always has some fun in the evenings too so it’s not all work!

Eric Ryherd Presenting

Express Controls founder and Z-Wave expert Eric Ryherd (aka DrZWave) will be presenting at the summit for the 4th consecutive year. Last years presentation was “Seven Things you probably don’t know about Z-Wave” and was well received. I was surprised how many engineers were completely unaware of the many new features and command classes that have been added to Z-Wave in the past couple of years. This year’s topic is “IoT Device Testing Best Practices“. I’ll go over some of the failures I’ve found over the last several years in both my products and other products I’ve tested.

Abstract

Z-Wave wireless Internet of Things (IoT) devices are hard to test! There are countless devices already in customers hands with bugs in them that make Z-Wave seem unreliable when in fact many of the issues are bugs in the device firmware.  Eric Ryherd, Z-Wave expert and consultant, describes some of the  failures that are still shipping today and best practices when testing your IoT device to reduce the chance your device fails in your customers hands. Simple command sequences sent one at a time by a test engineer is not representative of the real world packet storms that occur in an apartment building with complex RF reflections and multiple interfering RF networks. Your device has to work in the real world and to do that you need to simulate those terrible conditions that do not happen on the engineers desk.

Author Bio

Eric Ryherd licensed Z-Wave in 2003 to develop IoT devices before the term IoT even existed. Light switches, motion & temperature sensors, water valves and meters, hubs, window shades, remote controls are just a sample of the Z-Wave IoT devices developed and tested by Express Controls. Eric applies his Z-Wave expertise in consulting, training and assisting with Z-Wave Certification to companies of all sizes. Read more by Eric at his blog – DrZWave.blog.

Z-Wave Challenges in MDUs and How to Resolve Them

Deploying a robust Z-Wave network in MDUs (like apartment buildings or hotels) can be challenging unless you follow a few basic rules.
The most common problem in MDU deployment is that many installers fail to take advantage of Z-Wave’s number one technical advantage – the mesh network. Every always-on (wall powered) Z-Wave device adds a node to the mesh. But battery powered devices like door locks, sensors and many thermostats do NOT add nodes to the mesh – they merely benefit from other devices on the mesh network. A system where there is one Z-Wave hub and a door lock in each dwelling unit will result in a poorly performing system because there is no mesh! To build a reliable mesh, every device in the network needs at least two routes between the hub and every device on the network. This means you need at least one Z-Wave repeater or lamp module in every network.
An MDU can easily have dozens or even hundreds of units all within Z-Wave range of each other. If each unit has just a single Z-Wave hub and a door lock, then each unit causes interference with every other unit resulting in a cacophony of Z-Wave traffic. A better solution is to have one hub serve 5 or even 10 units with each unit having at least one always-on device within it to provide a good “mesh” node to access the battery powered devices. Always-on devices in adjacent units help provide routing pathways to improve the robustness of the network. The installer needs the proper tools to evaluate the best location for these always-on devices to ensure a high-quality mesh network with plenty of alternate routes.
Another challenge in MDUs is that things are always changing. An owner might install a mirror (which is a metal plate on glass) or a metal appliance that significantly alters the Z-Wave quality within the unit. Even though the mirror or appliance is not in between the hub and the door lock does not mean that it won’t cause connectivity problems. The solution to this issue lies again with the mesh network and having alternate routes. Since things are always changing, the hub needs to have a policy to “heal” the network occasionally to adjust to the changes in the environment.
If some door locks seem to have short battery life then you might be suffering from limitations in older, pre-500 series Z-Wave devices. Early generations of Z-Wave would wake up battery powered devices like door locks using only their NodeID to request which node to wake up. This works fine in single family homes since every node on the network has a different NodeID, but in an MDU with multiple adjacent Z-Wave networks, if the door lock in each unit is NodeID=2, then every hub will wake up every door lock in the building any time a unit needs to check on the battery level of any door lock. The solution is to ensure each adjacent installation has a different NodeID for door locks or battery powered nodes. Thus, apartment 101 will have the door lock as NodeID=02, apartment 102 will have the door lock as NodeID=03, and so on. The latest generation of Z-Wave solves this problem so as these newer locks come on the market this issue will disappear.

A few quick rules for deploying Z-Wave in MDUs:

  1. Always build a Z-Wave mesh
  2. Install fewer hubs
  3. Use tools like IMA to validate mesh networks
  4. Don’t build the same network in every unit
  5. Network must be flexible due to changing environments

EZMultipli How-To for SmartThings

SmartThings, now part of electronics giant Samsung, is a popular home automation platform and with the recently published Device Type fully supports the EZMultipli multi-sensor. Samsung_SmartThings_LogoSmartThings (a.k.a. ST) relies on the Cloud for processing which makes it flexible but is a little slower executing commands compared to a system with local processing. The ST user interface is exclusively thru a smartphone or tablet, there is no web interface for desktop computer access.  The system is easy to use with good support and an active user community.  SmartThings requires a $99 hub to interface to Wifi, Zigbee and Z-Wave devices. This post will show you how to get the most out of Express Controls EZMultipli Z-Wave MultiSensor. Refer to the EZMultipli User Manual for more details.

EZMultipli Multisensor

ezmultipli200The EZMultipli performs five functions:

  1. Motion Sensor
  2. Temperature Sensor
  3. Light Level Sensor
  4. Color LED indicator
  5. Z-Wave Range Extender

What sets the EZMultipli apart from the typical battery-powered motion sensors is that it is wall powered so you never need to change the batteries! Because EZMultipli is wall powered it functions as a Z-Wave range extender which adds another routing node in the Z-Wave mesh network. If your Z-Wave network is a little flakey and you have some nodes that are having trouble communicating reliably, adding an EZMultipli or two will provide additional routes for every Z-Wave node to talk to every other node. Then the sensors are a bonus!

Because EZMultipli is firmly plugged into an outlet, there is no mounting required. No screws, no tape, no mending of the wall when you move. This makes EZMultipli ideal for apartments, offices or other short-term uses where you’ll want to take it with you when you leave. But what if you don’t have an outlet in the right spot for detecting motion? Ah… that is a problem and not every device can solve every problem. EZMultipli was specifically designed with a wide-angle lens to capture motion in any direction out to about 12 feet. So it doesn’t have to be placed in the perfect location to be able to detect motion where you need it. It is ideal for kitchens, bathrooms and garages which often have unused outlets in handy locations. You can also put it in unused outlets under a table or chair. Obviously it isn’t much good behind a couch or other solid furniture. Some locations like hallways will have to use a battery-powered motion sensor because the sensor has to be in just the right place and there are no outlets nearby.

STEZMAddThingAnother placement problem involves pets. If you put the sensor down low in a typical wall outlet, virtually any pet from a cat to a small dog will trigger the motion sensor. You have to either put the sensor up on a higher outlet or in a room that pets are not allowed in when you need to detect if a burglar is in your home. In my case we always close off our home office from the pets during the day when we are not home. Only the EZMultipli in the office and the one in the garage will send us a text when the home is in Away mode.

Setup and Configuration

STEZMfullInclude EZMultipli into the ST hub in the normal way: Just click on the +Add A Thing button on the ST app. Next then press the button on the side of EZMultipli. You should get a device called “EZMultipli” which is the default name.
Rename the device if you want then click on Save and then OK.
You should now have the screen shown here. The main Tile at the top will turn the LED behind the lens on and off or if you click on the color circle you can change it to be any of 8 different colors. The motion sensor, temperature sensor and luminance sensor are on the next row of tiles. The REFRESH button will force the ST hub to poll EZMultipli to be certain it has the latest sensor readings. We’ll get to the CONFIGURE tile in the next section.

STEZMConfigAt this point, the best thing to do is to click on the Gear icon in the upper right corner. This brings you to the configuration screen where you can adjust various parameters to suite your needs. Generally the defaults will work fine for most applications. The next section will get into more details.

The temperature and luminance sensors are set to send a report every 6 minutes which is fine for an average sized Z-Wave network. However, if you have a lot of nodes (more than 50) in your network and specifically more than a few EZMultiplis, it would be better to reduce the frequency of sensor updates just to keep the traffic from getting clogged up. If you set the report frequency to 0 then that sensor will never send an update so if you’re not interested in a sensor then make its value 0. Click on DONE and then CONFIGURE to push the configurations down to the EZMultipli.

Initially the temperature and light level sensors may not have a value but in a few minutes the sensors will send readings the values will update.

For the first several minutes after joining the sensor to the ST hub the LED will blink white anytime is detects motion. You can use this to make sure it will detect motion where you want it too. If it is not detecting motion, try flipping it around in the outlet as this will change the orientation of the lens elements. Remember that EZMultipli detects MOTION, not people. So the people have to be moving within range of the sensor otherwise the lights will turn off while they are still in the room!

Configuration Parameters

Screenshot_20170410-125808EZMultipli has five configuration parameters that change how the device responds to various events.

  1. OnTime – Number of minutes the light will stay on when motion is not detected
  2. OnLevel – Dim level sent to Association Group 2 nodes
  3. LiteMin – Number of minutes between luminance reports
  4. TempMin – Number of minutes between temperature reports
  5. TempAdj – Temperature adjustment and 1/10ths of a degree F

Generally ST works best with a fairly short OnTime parameter of 2 minutes. This allows a SmartApp to control the amount of time a light stays on after motion is no longer detected. The current Device Type doesn’t provide access to the Z-Wave Association command class so that feature of the EZMultipli is not available. Thus, it is best to leave the OnTime at 2 minutes and configure your SmartApps to do all the other work. Refer to the EZMultipli User Manual for details on the other parameters.

After changing any configuration settings, be sure to click on the CONFIGURE button to push the configuration settings to EZMultipli.

SmartApps

STEZMSmartAppNow that you have a motion sensor, the most common thing is to turn a light on or off when there is motion or not. In ST that is done using a SmartApp. Go back to the home screen and click on Automation at the bottom. Then click on + Add a SmartApp and select Lights and Switches and then Smart Lights. You can then easily pick the light(s) you want to control and which sensor will trigger which lights as shown here. Turn on the Turn Off After Motion Stops and then pick a reasonable amount of time for the lights to turn off then no-motion is detected. In a hallway, this number can be quite short like 2 or 3 minutes. In a kitchen it needs to be more like 15 minutes and if sitting in a living room reading you might want it to be more than an hour. You can also set different timeouts using multiple SmartApps that are only active at certain times of the day. For example, I significantly extend the OFF time during meal times because while sitting at our kitchen table I don’t want the lights to turn off while we’re eating but no one has moved enough for the kitchen sensor to detect motion (which is next to the sink, not the table).

Color LED

The color LED of the EZMultipli is easily controlled using the phone app. But the more interesting use is to display things like when your garage doors are open or what the weather will be today (Blue for nice blue sky, Yellow for sunny and warm, Red for blistering HOT, White for snow, Green for rain, etc.). I’ll follow up later with more posts on how to do fun things like this with SmartThings and EZMultipli.

10 Questions when Reviewing Embedded Code

Design News posted a great article “10 Questions to Consider When Reviewing Code” and I’m just posting the list here. Follow the link for the full article with the details behind each question.

  1. Does the Program build without warnings?
  2. Are there any blocking functions?
  3. Are there any potential infinite loops?
  4. Should this function parameter be a const?
  5. Is the code’s cyclomatic complexity less than 10?
  6. Has extern been limited with a liberal use of static?
  7. Do all if…else if… conditionals end with an else? And all switch statements have a default?
  8. Are assertions and/or input/output checks present?
  9. Are header guards present?
  10. Is floating point mathematics being used?

My personal pet peeve is #3 – I am constantly reviewing that uses WHILE loops waiting for a hardware bit to change state. But what if the hardware bit is broken? Then the device is DEAD. Always have some sort of timeout and use a FOR loop instead of a WHILE loop. At least the code will move on and won’t be dead. Maybe it won’t work properly because of the broken hardware but at least the device can limp along.

How to support Over-The-Air (OTA) firmware update now that Micron has End-Of-Lifed the NVM Z-Wave needs

Sigma Designs Z-Wave chips rely on an external non-volatile memory (NVM) to store the routing tables and other data that needs to survive a power-loss. Unfortunately, Sigma chose an NVM that is single-sourced and what is even more unfortunate is that the source, Micron, has decided to End-Of-Life (EOL) the part in March of 2018. Semiconductor companies like Micron regularly EOL parts as technology moves on so I can’t fault them for that. Micron  gave plenty of warning as the EOL notice went out in 2013 giving you 5 years to prepare for the end. I and many other Z-Wave manufacturers didn’t realize the EOL until a couple of months ago when the NVM became out-of-stock at virtually all distributors! This shut down production lines and we were unable to build product! A potentially company killing event. Fortunately Micron was able to restock and we were able to ship product with only a slight delay. This temporary unavailability raises the critical nature of finding a replacement soon.

What are the Z-Wave NVM options?

Before deciding which NVM to use, you have to decide if you want to support Over-The-Air (OTA) firmware update or not. I highly recommend OTA because Z-Wave continues to evolve and being able to update the firmware in the field is a huge advantage. OTA requires enough NVM storage to hold a complete firmware image of the Z-Wave module which is 128K bytes AND the routing tables which is roughly another 32K bytes. The firmware image can be compressed which allows you to use a 1Mbit (128K byte) NVM but the price for a 2Mbit vs. 1Mbit is tiny and in some cases the larger ones are cheaper than the smaller ones because they are on a newer silicon technology.

Without OTA use commodity EEPROM

If you decide to not have OTA, the NVM options are not affected by the EOL because for slave devices you don’t even need an NVM. Simple slaves can store small amounts of application data in the on-chip FLASH of the Z-Wave chip. This saves the cost, size and power of the external NVM so in some cases this is the best way to go. For very small battery-powered devices like a key-fob, this is the way to go.

Routing slaves or controllers require an external NVM such as the  Atmel AT25256 32Kbit EEPROM. The EEPROM is a commodity device supported by several manufacturers so there is no EOL issue with these devices. Controllers and routing slaves need to store  the routing tables in NVM which are many K bytes of data. The EEPROM devices are well suited to this task because you can write to single bytes of the EEPROM at a time. The serial FLASH chips are not able to write to single bytes which is the major problem. Gateways or other controllers with another micro on-board can update the Z-Wave firmware using either the SPI pins or the UART/USB. The code to burn the firmware into the Z-Wave chip has to be written by you or contact Express Controls and we can sell you a small package to do it.

With OTA use a single source serial FLASH

If you decide to include OTA in your product (and I highly recommend it), then your only solution is to use the Adesto Tech AT45DB0xx family of serial FLASH chips. The Sigma 500 Series Integration Guide (document number INS12213) lists only the Adesto part as the sole supported option at the moment. Sigma is actively looking for alternatives but there don’t appear to be any at the moment. The problem I have with the Adesto part is that it is only available from Adesto, there is no second source. This is a unique part and worse, it has a completely unique pinout as shown below. Using the Adesto part REQUIRES PCB RE-LAYOUT! Existing designs that have already passed FCC regulatory and Z-Wave compliance may not be able to switch to the Adesto part because of the pinout differences. The pinout of each part is shown below. The pins are completely scrambled. The signals are basically the same function but their placement is scrambled.

Z-Wave Experts consulting and IoT product development

The only solution is to put both footprints on the PCB to enable the option of purchasing whichever part is available and cost-effective.

Why doesn’t Sigma support commodity serial FLASH chips? The problem with commodity serial FLASH chips is that they require you to erase an entire sector (4096 bytes) any time you want to write even one byte of data. The Micron and Adesto parts both have Page Write capabilities where a page is only 256 bytes. Every time you write a single byte of data to the NVM the Sigma code will READ 256 bytes, erase the entire 256 bytes (which is a single SPI command), and the write the 256 bytes with the updated byte of data. Any time you write more than one byte to the EEPROM you should be using the MemoryPutBuffer command and not the MemoryPutByte. Supporting commodity FLASH chips would require reading/storing/writing 16 times more data with each write. That would slow many operations down to the point of unusability.

Comparing the NVM Parts

The Adesto part is specifically designed for IoT devices and has a number of really handy features. Specifically it has an Ultra Deep Sleep mode of only 1uA. The Adesto NVM has a wide voltage range which ensures it will work in battery-powered devices even as the battery approaches its end of life. The Sigma Z-Wave 500 series chips are able to operate down to 2.3V and the Adesto part is well below that.

The table below gives a breakdown of the options for NVM with Z-Wave. Using the on-chip FLASH for a few dozen bytes of application storage is of course the lowest cost option but limits the routing capabilities of the node. This option is ideal for Key-fobs or other very space/cost constrained devices that don’t need OTA. The EEPROM is fine for controllers that can be reprogrammed using a second micro. The Micron part is not recommended since it will soon be unavailable. The Adesto part is expensive and is single sourced and has a unique pinout but it is the only solution at the moment.

Spec None EEPROM M25PE AT45DB
PinOut NA Std Std Non-Std
OTA No No Yes Yes
Size on-chip 32Kb 2Mb 2Mb
Write 1 byte 1 byte 256 bytes 256 bytes
Vcc 2.3-3.6V 1.8-5.5V 2.7-3.6V 1.65-3.6V
Sleep 0 10uA 10uA 1uA
Cost1 $0.00 $0.32 $0.42 $0.75
Use Case Small battery powered devices like Key Fobs Controllers with second micro for firmware update OBSOLETE! Recommended

If Sigma can figure out how to work with the larger 4Kbyte sector sizes of commodity serial FLASH chips then the cost of a Z-Wave device can drop by over 50 cents resulting in a couple of dollar cheaper retail price. All Z-Wave manufacturers should be pressuring Sigma to come up with a cheaper solution.

Notes:

  1. NVM costs are 1K pricing from online distributors Q1 2017 and should be used for comparison purposes only – your results will vary

EZMultipli How-To for Vera

vera_logo_tmVera is one of the more popular home automation platforms and with the UI7 release it fully supports the EZMultipli muli-sensor. The main selling points of Vera are “no monthly subscription fee, no contracts and no hassles” which pretty much sums Vera up. Vera is an easy to use system with good support and an active user community who are often quicker to respond to questions than the Vera technical support team.  Vera has several platforms to choose from. I’m using the VeraEdge in this How-To which for only $69 is a good deal. This post will show you how to get the most out of Express Controls EZMultipli Z-Wave MultiSensor and specifically how to use it with Vera UI7. Refer to the EZMultipli User Manual for more details.

EZMultipli Multisensor

ezmultipli200The EZMultipli performs five functions:

  1. Motion Sensor
  2. Temperature Sensor
  3. Light Level Sensor
  4. Color LED indicator
  5. Z-Wave Range Extender

What sets the EZMultipli apart from the typical battery-powered motion sensors is that it is wall powered so you never need to change the batteries! Because EZMultipli is wall powered it is a Z-Wave range extender and adds another routing node in the Z-Wave mesh network. If your Z-Wave network is a little flakey and you have some nodes that are having trouble reporting in reliably, adding an EZMultipli or two will provide additional routes for every Z-Wave node to talk to every other node. The sensors are just a bonus!

Because EZMultipli is simply plugged into an outlet, there is no mounting required. No screws, no tape, no mending of the wall when you move. This makes EZMultipli ideal for apartments, offices or other short-term uses where you’ll want to take it with you when you leave. But what if you don’t have an outlet in the right spot for detecting motion? Ah… that is a problem and not every device can solve every problem. EZMultipli was specifically designed with a wide-angle lens to capture motion in any direction out to about 12 feet. So it doesn’t have to be placed in the perfect location to be able to detect motion where you need it. It is ideal for kitchens, bathrooms and garages which often have unused outlets in handy locations. You can also put it in unused outlets under a table or chair. Obviously it isn’t much good behind a couch or other solid furniture. Some locations like hallways will have to use a battery-powered motion sensor because the sensor has to be in just the right place and there are no outlets in that place.

Another placement problem involves pets. If you put the sensor down low in a typical wall outlet, virtually any pet from a cat to a small dog will trigger the motion sensor. You have to either put the sensor up on a higher outlet or in a room that pets are not allowed in when you need to detect if a burglar is in your home. In my case we always close off our home office from the pets during the day when we are not home. Only the EZMultipli in the office and the one in the garage will send us a text when the home is in Away mode.

Setup and Configuration

The first and most important step is to make sure you are running Vera Firmware Version 1.7.2406 or later. Check the firmware via Settings->Firmware and the screen will show you which version you currently have and if there is an upgrade available. You can include the EZMultipli into Vera but previous firmware versions didn’t understand the Z-Wave Notification command class used by EZMultipli so it isn’t very usable without at least this version.

Include EZMultipli into Vera in the normal way: Devices->Add Device->Generic Z-Wave Device->Next->Next then press the button on the side of EZMultipli. You should get a device called “EZM” which is the default name. Pick a room. Then click on FINISH.

You’ll then have three new devices:

  1. vera3sensorsEZM which is the motion sensor
  2. _Temperature Sensor which is obviously the temperature sensor
  3. _Light Sensor which is the light level in the room

Initially the temperature and light level sensors don’t have a value but in a few minutes the sensors will send readings the values will update. Rename the devices to more meaningful names  by clicking on the > and entering a new name. These three sensors are the main sensors – but where is the color LED? Currently you have to load a Plug-in to use the color LED. Hopefully in a future release Vera will add support for the Z-Wave Color Command Class and we won’t need the plugin anymore. To add the plugin click on Apps->Install Apps and then enter “EZM” into the search bar and the EZMultipli Color Utility will come up. Click on DETAILS and then install the app. While you’re at it, search for DataMine2 graphing plug in and install that too.

vera4sensorsWith the plugin installed there are three more devices but the only one that is interesting is the EZM Light 2 which has the 8 LED color buttons as shown here. Assign that device to the same room as the other EZMultipli sensors. I create a virtual room called ZZZVirtual to put all the extra stuff I don’t normally want to see so it’s at the bottom of the screen.

If you wave your hand in front of the motion sensor, the EZM device will go red indicating the sensor has detected motion. If there is no motion for 10 minutes it will go back to being grey which means no-motion. NOTE! The motion sensor sends a MOTION command when motion is initially detected. Then, only after the OnTime number of minutes of there being a complete lack of motion will the No-MOTION command be sent. The sensor does NOT send a motion command every time it detects motion (though you can enable it to do that).

Vera Scenes

The most common thing you want to do with a motion sensor is to turn on a light when motion is detected and turn it back off again when no one is in the room. With Vera, we do this with Scenes. Click on Scenes->Add Scene. This will open up a wizard that will guide you thru the process. Step 1 picks the device which in this case is EZM and we’ll choose “Whenever EZM detects motion whether is armed or disarmed”. Step 2 is to pick a light to control. In this case we’ll chose the EZM Color and chose the green color. Click on Next step, scroll down and name the scene then click Finish. Next click on the RUN button just to be sure the scene works. There are tons of other options you can choose as part of the scene so try them out and experiment. You can set the scene to only run at certain times of the day or certain days of the week. This is handy for example to set the brightness of a dimmer to be only 20% late at night when all you really want is a night lite to get down a hallway without stepping on the toys your kids left in the hallway.

Configuration Parameters

EZMultipli has five configuration parameters that change how the device responds to various events.

  1. OnTime – Number of minutes the light will stay on when motion is not detected
  2. OnLevel – Dim level sent to Association Group 2 nodes
  3. LiteMin – Number of minutes between luminance reports
  4. TempMin – Number of minutes between temperature reports
  5. TempAdj – Temperature adjustment

The most important parameter is the OnTime parameter. As the name implies, OnTime is the number of minutes the lights will be ON after motion stops being detected. When you walk within range of the motion sensor, Vera receives a Motion event immediately. Vera can then turn lights on or if you configure association group 2 EZMultipli can control the lights directly. Let’s say you then walk around the room for 5 minutes and then walk out of the room. Then 10 minutes later, Vera will be sent a No-Motion event. Why 10 minutes and not 5? Because OnTime is set to 10 minutes which starts counting down when you left the room, not when you entered. Here are some recommended values for the OnTime parameter:

  • OnTime=0 disables sending OFF commands. Only ON commands are sent. This setting is not recommended.
  • OnTime=1 is the minimum setting. For example, late at night you could set the timeout to be only the 1 minute since you’re probably just passing thru. But at dinner time you want a much longer timeout of 30 minutes to prevent Vera from turning the lights off at the dinner table while you are eating dinner. Having to wave your arms in the air in the middle of dinner to turn the lights back on will lower your Wife-Acceptance-Factor (WAF).
  • OnTime=5 minutes is generally a good setting for hallways or other places that you are actively moving thru and only need the lights on while moving thru the space
  • OnTime=10 default setting which is OK for most use cases.
  • OnTime=30 minutes is recommended for rooms where people might be sitting for some time such as in an office or watching TV.
  • OnTime=60 minutes or more might be necessary for a room where someone might be sitting for a long time perhaps reading.

Remember that EZMultipli detects MOTION, not people. So the people have to be moving within range of the sensor otherwise the lights will turn off while they are still in the room!

veraconfigTo change parameters, click on the > on the EZM device and then the Device Options to get the screen shown here. If there are no configuration settings shown, click on the Add Configuration Settings button and one will be created. Select “1 byte dec” in the Data Size field then enter the desired value for the OnTime parameter in the Desired Value field. Then click on Save Changes.

Refer to the EZMultipli User Manual for details on the other parameters. The challenge with the Vera parameter user interface is that it only uses unsigned integers whereas many parameters are signed values. For example, parameter 5 is the TempAdj parameter which is in 1/10ths of a degree Fahrenheit and is a signed number. So if you want to adjust the temperature readings of EZMultipli up by 1.2 degrees you enter 12. But if you want to lower the readings by 1.2 degrees you have to enter the number of 256-12=244. The other parameters are unsigned 1 byte integers so they don’t require this crazy math.

Z-Wave Association Direct Control of Lights

EZMultipli also supports the Z-Wave Association Command class. Associations are used to tell EZMultipli to send ON/OFF commands directly to other Z-Wave devices with out requiring a scene or even talking to Vera. The advantage of Associations is that it results in very fast response times and even if Vera isn’t running the lights will come on and off automatically. Note that if EZMultipli controls a device via Associations, the Vera UI won’t show the new state of the controlled device until it gets around to polling it which can be several minutes later.

Setting associations in Vera involves first clicking on the EZM device and then Device Options. Associations are just below the configuration parameters. Enter a 2 in the Group ID field and then Click on Add Group. Refresh the screen and there should now be Group ID 2. Click on SET and choose the device you want to directly control using EZMultipli. Finally click on Apply Changes. Once this is set, the device that is now associated will automatically turn on when motion is detected and turn off after OnTime minutes when motion is no longer detected.

 

Well that should get you started using EZMultipli with Vera. Future posts will include more advanced usage of the color LED and how to use the other sensors. If you have an interesting use case for the EZmultipli please add a comment or send an email to DrZwave at ExpressControls.com.

EZMultipli How-To for HomeSeer HSM200

HomeSeer HS3 is my favorite smart home software. I use the HomeSeer HomeTroller Zee S2 to run my home. The Zee S2 is a Raspberry Pi (RPi) with a built-in Z-Wave interface that runs the HomeSeer HS3 software. The part I like the most about HomeSeer is that the processing runs locally on the RPi which makes the response time very snappy compared to the cloud based systems. The RPi has plenty of horsepower to serve the web pages and run the events that control my home automatically and it does it all with a mere 6 Watts of power. Compared to having running on a PC 24/7/365 at typically 60+ watts, the RPi is a green and low-cost alternative. HomeSeer has a very active user community on their forums and if you have a question on how to do something, just ask and someone will respond quickly. HomeSeer sells the EZMultipli under their own brand name as the HSM200. For this post I’m going to show you how to get the most out of Express Controls EZMultipli Z-Wave MultiSensor and specifically how to use it with HomeSeer. Refer to the User Manual for more details on EZMultipli/HSM200.

ezmultipli200EZMultipli Multisensor

The EZMultipli performs five functions:

  1. Motion Sensor
  2. Temperature Sensor
  3. Light Level Sensor
  4. Color LED indicator
  5. Z-Wave Range Extender

What sets the EZMultipli apart from the typical battery-powered motion sensors is that it is wall powered so you never need to change the batteries! Because EZMultipli is wall powered it is a Z-Wave range extender and adds another routing node in the Z-Wave mesh network. If your Z-Wave network is a little flakey and you have some nodes that are having trouble reporting in reliably, adding an EZMultipli or two will provide additional routes for every Z-Wave node to talk to every other node. The sensors are just a bonus in that case!

Because EZMultipli is simply plugged into an outlet, there is no mounting required. No screws, no tape, no mending of the wall when you move. This makes EZMultipli ideal for apartments, offices or other short-term uses where you’ll want to take it with you when you leave. But what if you don’t have an outlet in the right spot for detecting motion? Ah… that is a problem and not every device can solve every problem. EZMultipli was specifically designed with a wide-angle lens to capture motion in any direction out to about 12 feet. So it doesn’t have to be placed in the perfect location to be able to detect motion where you need it. It is ideal for kitchens, bathrooms and garages which often have unused outlets in handy locations. You can also put it in unused outlets under a table or chair. Obviously it isn’t much good behind a couch or other solid furniture. Some locations like hallways will have to use a battery-powered motion sensor because the sensor has to be in just the right place and there are no outlets in that place.

Another placement problem involve pets. If you put the sensor down low in a typical wall outlet, virtually any pet from a cat to a small dog will trigger the motion sensor. You have to either put the sensor up on a higher outlet or in a room that pets are not allowed in when you need to detect if a burglar is in your home. In my case we always close off our home office from the pets during the day when we are not home. Only the EZMultipli in the office and the one in the garage will send us a text when the home is in Away mode.

HomeSeer Motion Events

Now that we have a sensor in an outlet that will detect motion, what do we do with that information? Naturally the most common thing is to turn lights on and off and to send a text when motion is detected and the house is in Away mode (security is enabled).ezmeventonoff

These two events are the most basic ways to control a light with motion. The light will come on when motion is detected but only if it is after sunset and before sunrise. When the sensor has not detected motion for several minutes it will change state to No Motion and the light will be turned off. Note that I also turn the light off at sunrise just to be sure its off during the daytime. The light I’m controlling with these events is the color LED of the EZMultipli itself and you can set the color to any of eight different colors.

Z-Wave Association Direct Control of Lights

EZMultipli also supports the Z-Wave Association Command class. Associations are used to tell EZMultipli to send ON/OFF commands directly to other Z-Wave devices without requiring events or even talking to HomeSeer. The advantage of Associations is that it results in very fast response times and even if HomeSeer isn’t running the lights will come on and off automatically.

Setting associations in HomeSeer involves first clicking on the root device of the EZMultipli or HSM200. Then click on the Z-Wave tab as shown here.

ezmhs3assoc

Click on the little yellow triangle to open the Associations menu. Next click on Update which will cause HomeSeer to double-check the associations set in the device. HomeSeer automatically assigns itself to Group 1 so that it will get the Motion/NoMotion Notifications. To turn lights on and off directly from EZMultipli, Click on the Association Group drop down menu and select Group 2. Then pick the device to be controlled and then Add Association. I recommend then clicking on Update again just to be sure. It is also a good idea to click on Full Optimize which will improve the Z-Wave routing thru the mesh network. Once this is done, the light in Group 2 will turn on when motion is detected and off after motion is no longer detected for 10 minutes.

Configuration Parameters

EZMultipli has five configuration parameters that change how the device responds to various events.

  1. OnTime – Number of minutes the light will stay on when motion is not detected
  2. OnLevel – Dim level sent to Association Group 2 nodes
  3. LiteMin – Number of minutes between luminance reports
  4. TempMin – Number of minutes between temperature reports
  5. TempAdj – Temperature adjustment

The most important parameter is the OnTime parameter. As the name implies, OnTime is the number of minutes the lights will be ON after motion stops being detected. When you walk within range of the motion sensor, HomeSeer is sent a Motion event immediately. HomeSeer (or via Group 2) can then turn lights on. Let’s say you then walk around the room for 5 minutes and then walk out of the room. Then 10 minutes later, HomeSeer will be sent a No-Motion event. Why 10 minutes and not 5? Because OnTime defaults to 10 minutes which starts counting down when you left the room, not when you entered. Here are some recommended values for the OnTime parameter:

  • OnTime=0 disables sending OFF commands. Only ON commands are sent. This setting is not recommended with HomeSeer.
  • OnTime=1 is the minimum setting. Use this value in collaboration with HomeSeer Timers to vary the off time based on the time of day. For example, late at night you could set the timeout to be only the 1 minute since you’re probably just passing thru. But at dinner time you want a much longer timeout of 30 minutes to prevent HomeSeer from turning the lights off at the dinner table while you are eating dinner. Having to wave your arms in the air in the middle of dinner to turn the lights back on will lower your Wife-Acceptance-Factor (WAF).
  • OnTime=5 minutes is generally a good setting for hallways or other places that you are actively moving thru and only need the lights on while moving thru the space
  • OnTime=10 default setting which is OK for many use cases.
  • OnTime=30 minutes is recommended for rooms where people might be sitting for some time like an office or watching TV.
  • OnTime=60 minutes or more might be necessary for a room where someone might be sitting for a long time perhaps reading.

Remember that EZMultipli detects MOTION, not people. So the people have to be moving within range of the sensor otherwise the lights will turn off while they are still in the room!

Refer to the EZMultipli User Manual for details on the other parameters.

To change parameters, click on the root device from the Home screen and then the Z-Wave tab and then the Settings yellow triangle to get the screen shown here.

ezmhs3config

 

 

HomeSeer knows about parameters 1, 3 and 4 but you can adjust any parameter via the Set Configuration Parameters box at the bottom of the screen. You have to “Use at your OWN risk” but the parameters are straightforward enough – I think you can handle it. The biggest challenge with parameters is setting values greater than 127. Officially all parameters are supposed to be twos-complement but you can enter values greater than 127 by using the twos-complement equivalent.

Well that should get you started using EZMultipli with HomeSeer. Future posts will include more advanced usage of the color LED and how to implement a variable timeout. If you have an interesting use case for the HSM200 please add a comment or send an email to DrZwave at ExpressControls.com.