Which one should I use – A Review of X-10 Controllers
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Ido Bar-Tana, ido_bartana@yahoo.com Updated May 20, 2004 IntroductionTo a large extent, a home automation controller defines the entire system. First and foremost, it defines the system protocol. In addition, it sets the performance envelope of the system in terms of expandability, flexibility and reliability. Finally, in many cases, it is the single most expensive item in the automation system. Thus choosing a controller warrants some thought.
This article reviews nine X-10 controllers, and attempts to provide a clear picture of what’s out there. It is my hope that this will aid you in deciding which X-10 controller would best suit your needs.
A note before we start: this article is sparkled with many links to pages in smarthome.com. Although I don’t endorse them, I do applaud their web site. It very thoroughly covers many X-10 products and has an extensive and thorough description of every item (well, at least their pros). If you’re new to X-10, their catalog is the best X-10 Beginner’s Guide I can think of.
That out of the way, lets define a controller as a software programmable X-10 transmitter device. I added ‘software’ to the definition so as to exclude consoles such as the mini-controller. On the other hand, I didn’t confine the definition to ‘transceivers’ because I want to cover one-way devices such as the classic CP290 and the CM17A (Firecracker).
There are three quite distinct categories in controllers.
Next, let's define the benchmark - a meter to rate each controller. I’ll rate the controllers using five categories, in each rating a controller from 1 to 5 stars. The categories that I think matter are:
Finally, I'll give an overall score: an approximate, opinionated weighted integral of all the criteria. This might be very different from your needs and wants.
Now that we’ve laid the ground rules, let them start marching in. Teasers and AppetizersAppetizer I: CM17A/CM18A (Firecracker)
The combination of the computer interface and the wireless transceivers enables sending commands from the computer to the home power-lines, controlling the lamp module. Praise:
$6 was a
hard price to beat, but not such a great deal at $40. The low price and small size of the computer device quickly prompted people to write software for it. You can find an ActiveX control for the firecracker, attempts were made to implant it into a 3com Palm, and the limited original software that came with the device was quickly enhanced to include web control and macros (chains of commands). Gripes: The wireless transceiver module is limited to 16 devices. Additional devices would require additional transceivers. Worst, your computer can only send commands. It cannot receive the status of devices (such as sensors) and thus cannot issue commands in response to changed states or events (other than time of day etc). The wireless transceiver also has (as of this writing) a serious hardware bug: many people documented in the home automation newsgroup lockups when trying to dim lights using the wireless transceiver. The only way to release the transceiver from the lockup was to unplug it from the mains. Overall, The CM17A kit will give you no more than a taste and proof that you indeed can control a light using your PC very easily. This is a far cry from anything that falls under ‘home automation’ in my dictionary. I think you will soon grow tired of the demo, and will quickly look for a better controller. I argue that even as a demo it defeats its purpose because it is so limited and because home automation isn’t. If you want a much better taste for home automation, shell out $10-20 at Ebay.com and get a HomeDirector kit.
Appetizer II: CP290
Praise: For
starters, it’s a combo of a controller and a console. The console has eight
ON/OFF buttons that can control eight devices in one house code, and through
software any of the 256 X10 address space. Another quite unique
hardware feature is that events programmed into the CP290 can be played right on
time or randomized around the programmed time for ‘lived-in’ look. Finally, it
has a battery that saves programmed events through power-downs. Of course no
transmitted event will get through the power-line during power-outs, but at
least when power is restored, the controller will still have the events stored
in it. It has its own internal clock so it can be disconnected from the host and
play out the events.
Gripes: the worst single shortcoming of the CP290 is that it is a one-way (transmit) only device. In fact, I think that many, myself included, would have continued to use it and not switch to ActiveHome or other, more expensive controllers, if it wasn’t for this limitation. Priced comparably to ActiveHome, a two-way controller, it fails on that criteria. Being old and retired by ActiveHome, the CP290 doesn’t get much software support on the newer operating systems. However, it has plenty of DOS based programs and I’m sure if you look hard enough, some Windows as well. Programming the CP290 is harder than the newer controllers, but it has been done before and you can find the code if you look for it. One known pesky problem with the CP290 is that the clock drifts badly (in excess of a minute per month), though there is a remedy for this that involves replacing the clock chip with a better one. There is no low-battery indicator, and the internal memory can store only 128 events, so it can’t be disconnected from the host for too long. Overall, for the price, there is no reason to buy this old timer (no pun intended) today. ActiveHome displaced it. Mainstream ControllersMainstream I: CM11A (ActiveHome, HomeDirector)
Praise: The activehome is the first controller on our march that finally introduces two-way. This opens up a flood of situations that can be handled much better than with the previously reviewed controllers. The CM11A also strikes a good balance between price and features. It enjoys the status of widest applications base support. I am not aware of any new general purpose HA program that won’t interface with the Activehome. It is easy to install and comes in many flavors: the CM11A is made for the 110v power-line voltage. CM11K is for 220v, and there are versions with French, German and British plugs. The HomeDirector is a CM11A under the IBM brand. Radio Shack calls it something else, and the list goes on. Marketing really sets this controller apart. Technically, however, this
controller boils down to a dumbed-down CP290, stripped from the console, but
with power-line sensing circuitry. It has less memory then the CP290 but
introduces macros, which are chains of events.
ActiveHome does a good job of reporting collisions. It not only reports the presence of collisions, it also reports the colliding command. This is important in order for the host to keep a correct state table of the modules. This and the Ocelot described later are, to the best of my knowledge, the only controllers with a colliding-command report. This controller is one of the very few that understands dim/bright commands sent by other transmitters, and understands extended commands. The only other one I know of is the Lynx-10 PLC, which costs more than twice as much (see below).
Gripes: There are plenty of documented problems with the CM11A in the reliability arena. There are no less than four different ways the CM11A can hang! In addition, there have been reports of the device overheating to the point of too hot to touch. All that doesn’t score too well for its reliability. Overall: I believe it is a sensible choice for a controller unless you either know how to solder or are looking to automate your infra-red equipment as well. If that’s not the case, I think your search ends here.
Mainstream II: The LynX-10 kit
Praise: There are good assembly instructions on my x10 knowledge base site. The kit board can be placed inside the PC, on the bottom, on top of a plastic sheet (so nothing gets shorted). In addition, the extra space on the right of the kit printed circuit board can be used for something useful. For example, you can build a watchdog timer that keeps an eye on your entire home automation system, and if something fails, resets the PC. In short - this is an ideal controller for enthusiasts with some electronics backgrounds. Other nice features include extensive error reporting (carrier lost, command timeout, collisions etc), statistics counter and it handles dimming a bit better. Programming is exceedingly easy for the LynX-10 and it comes with a robust
general-purpose program. Gripes: This is a general one from this point onwards. To communicate with the power-line, the LynX-10 uses a module called TW523. This $15-20 module sits between the power-line and the LynX-10, so take its price into account. Another issue with the TW523 is that it does not support extended codes and does not receive DIM commands. Thus, the all TW523-using devices won’t ‘hear’ advanced two-way modules that use extended codes or report dimming status. Moreover, the LynX-10 needs a host computer running all the time. There is no backup battery. However, there is a small pro here: for what the LynX-10 (and controllers reviewed from this point down) can do, you probably want a host computer. Some examples: irrigation program that is forward looking based on the forecast downloaded from the Internet; control through the Internet or phone; speech synthesis and recognition. For these and others, you’ll have a PC running anyway, so it’s smart to move as many features as possible from the hardware domain to the software domain, where the solutions are much easier, cheaper and more scaleable. Overall: this is the first controller reviewed so far that addresses the two-way issue while not compromising reliability, and in addition has some unique features. If you don’t need or plan on IR control, and am willing to solder, the LynX-10 kit is in my opinion, a sure bet. Marrick Ltd, makers of the LynX-10 are working on a $100 controller that has encompassed the TW523 and supports extended codes. It’s called the LynX-10 PLC. Mainstream III: Ocelot
Praise:
Concentrating on the
controller itself, the CPU-XA/Ocelot has an internal clock and is battery
powered. It has a relatively tremendous program space of 16K (compared to 1K for
ActiveHome), and the big add-on is the built in infrared controller. Ocelot
costs about $200 and can address a touch-sensitive screen (the ‘Leopard’) and generally, is more
scalable to future enhancements.
A unique ‘feature’ with this controller is the dedicated and responsive tech support from Adicon. The level of support received many compliments in the home-automation newsgroup.
Gripes: The Ocelot shares the same limitation with the LynX-10: it needs the TW523, and thus is prone to TW523 limitations described above.
In addition, the price of add-on quickly adds up.
Overall, the Ocelot makes a superb X-10 controller, which is very expandable and flexible. The only reservation is the relatively high price tag.
High priced ControllersA note before reviewing the high end devices: the price range for these controllers is $600-1000. At this price range, the bottleneck won’t be the hardware – it will be the protocol. The X-10 protocol has some inherent deficiencies in it. For starters it is very slow. It takes around a second from command sent to command performed. Macro execution (several lights performing) may take much longer. Many people find that mildly irritating. People who are willing to pay $700 for the controller alone may find it very irritating. Secondly, the protocol is collision prone, and it is difficult to load the system with more than three-dozen transmitters (sensors, two-way modules etc) and be able to respond to them well (i.e. to keep the state table right). In other words, the X-10 protocol does not scale up very gracefully. What this boils down to is that at this price range, X-10 may be the wrong technology for you. X-10's greatest benefits are low cost retrofits. If you’ve ventured into this price range, it may be worthwhile to also look for other alternatives such as dedicated control wires to each switch or control by wireless. Now that you’ve been warned, let’s continue on: TimeCommander Plus (by JDS)
Praise: This is an integrated unit with very powerful hardware features. It can easily control HVAC and handle alarm sensors and actuate sprinkler relays. The hardware for it is built in.
Gripes: There is
no direct support for IR (which is a given in the Ocelot). For IR support under
the TimeCommander Plus, one needs to add the
Infrared Xpander for $300. Surprisingly, at this price range (>$500) the controller still needs the TW523 for X-10, with all the limitations of the latter described above. The fact that the I/O is built inside the controller may be a mixed blessing: sometimes you’d have the sensors input far from the controller, or alternatively, will need to control far relays. Both situations will necessitate wiring, which defeats the entire underlying benefits of X-10. Overall: a good choice for high-end systems, if your plans call for many sensors and controls actuated from a central location. Touchlinc (By smartlinc)
Gripes: in order to have sequences of commands, the Touchlinc needs to be tied to another controller, which in turn triggers pre-programmed commands. As all its predecessor two-way controllers except the Activehome, it too needs the TW523.
Stargate (by JDS)
Praise:
A
high-end controller integrating many components others sell separately. Gripes: As it’s predecessors, this controller needs the TW523 for two way X-10. At $1,000 the added value is, in my opinion, marginal. With a host PC and a freely downloadable Direct-Speech-Synthesis activeX control (you can get it here), one can very easily incorporate the added features, and while at it, also add speech recognition. There are $30-$50 products that do X-10 telephone transponding, or if you have a voice modem, you can do it with software. In short, the expense of moving features from the software domain to the hardware domain can get substantial, and is usually not warranted. Overall: an extreme controller for this technology.Concluding remarks and guidelinesThere are, of course, other controllers besides the ones reviewed. However, most of them fall somewhere around the ones described.X-10 is by its nature modular and incremental. However, changing a controller is usually more involved than simply adding more modules to the system. Often, the software must be replaced, and the controlling commands rewritten or revised for the new features. There’s usually a different interface with new idiosyncrasies and learning curve. Therefore, for ‘general-purpose’ home automation, my suggestion is to avoid the under-achievers. Looking at what seems basic today for home-automation, a controller must be able to do two-way X-10.Another general suggestion is to think the system through. This is easier said than done, though. Looking forward, think about what you’d like to have in say, a year: would you want sprinkler automation? Would you want audio/video auto-control? Next, check the ‘boundary conditions’: would you have a PC running continuously? Can you wire all your inputs to a central location? How reliable must the system be? How comfortable are you with rolling your own code? Answering these and other questions can rapidly steer you to the right X-10 controller for you.
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