Direwolf,
Nice to meet another controls type. I've been designing aerospace fuel controls systems for 30 years. As you said, if it didn't do what we told it to do we want to know about it (now!). If a problem is non-critical we'll begin setting health flags. Otherwise backup channels and failsafe systems begin to kick in.
There's really no equiavlent to this with powerline automation. The powerline itself is the weak link. The devices we plug into the powerline generate noise and/or absorb X10 and Insteon signals. If there is enough noise/absorption the system fails. There is no backup other than re-trying the communication.
Insteon improves on the X10 communication protocol in a few ways:
- Each transmission is encoded with a CRC for error checking by receivers.
- All Insteon devices that "hear" a message will repeat the message (0 - 3 times) as commanded by the controller.
- Receivers transmit an ackowledge upon receiving a valid tranmission (your feedback). This is only used for device to device commands, not broadcast commands.
- If the transmitter does not receive an acknowledge, it will increment the repeat count (up to 3) and resend the message up to 5 times.
In summary, while Insteon does provide error checking, multiple repeaters, and acknowledge/retry logic, it's still single thread. If I place a noise source between the transmitter and receiver I can break it.
Zwave and Zigbee attempt to get around this with RF and multiple repeaters but they are far more expensive and have some of their own problems (I'm really not qualified here). Personally, I don't like the idea of 900Mhz all over my house (Yeah, I'm an oldtimer - don't own a cell).
As a result of the above there are many things that I would never trust to a HA system -
- Security - Hardwired
- HVAC - Hardwire, dedicated controller
- Appliances - Hardwired (Appliance module is a misnomer, these should be called on/off relays switches. A flourescent lamp - fine, my freezer - not on your life).
Sorry for the negativity. Like you, I'm an Engineer - I have to tear things apart to find their good points.
On the lighter side -
It is definately possible to "clean" and "couple" your powerlines to allow X10 systems to be reliable. Unfortunately, this tends to be a maintenance item. We typically keep adding devices to our homes and breaking our X10 systems.
Going for an "inexpesive" solution, there are a number of X10-2way units that can be interrogated for their status. Using ActiveHomePro and the CM15a (the link you provided) you can use a macro to poll these devices and re-issue commands if they don't respond. Keep in mind, you're using the same powerline that didn't transmit the command the first time. It's entirely possible that you won't get a response to your status query.
Insteon units are all X10-2way compatible. They can provide a nice bridge while you're getting your feet wet. I've used my Insteon units for 2 years with the CM15a/ActiveHomePro package while I was waiting for a "stand alone" Insteon controller. Do NOT purchase the PLC version of the Insteon controller that you referenced previously. Smartlabs was never able to get the promised "macro download" functioning and they have abandoned future development. On the other hand, I'd say the ISY-26 would be overkill (way to much investment before you have a good idea on how you want to proceed).
For your pump application,
Steven_R's suggestion of the X10 outlet was a good one. These is an Insteon version of this available as well (or will be available on 12/17). For a controller, I'd recommend either the mini timer (if you want to get your toe wet) or the AHP/CM15a/Smart Macros package (can usually be purchased for $49 on sale). The CM15a/Smartmacro package would allow you to interrogate the status of the Insteon Outlet (I believe - don't have one yet).
Boiler