Whats the difference between an Insteon PLC vs a PLM?
- Thread starter RichTJ99
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upstatemike
Senior Member
I don't think in its current state that a PLM is in fact better than a PLC. The PLC is considered sub-optimal for Computer control because it has a slow PC interface, does not support the extended command set of the Insteon specification, and depends on software loaded into the device that has always been buggy and unreliable.
The PLM removes the software layer so that the application builder is not constrained by it and can manage all of the logic within the PC. The current PLM does support the extended Insteon command set but suffers from heat related lockup problems and insufficient memory for any practical application. I understand the lockup issue is being addressed by reducing the trasmit power of the PLM to prevent excessive heat generation but this has introduced other compromises. I understand it is also easy to exceed the maximum number of records that can be held in the memory available, creating a situation from which you cannot easily recover.
The only practical available solution (that I am aware of) at this time is to either to keep your Insteon installation extremely small or use PowerHome with a PLC. PowerHome compensates for most of the shortcomings of the PLC by only storing a responder link for each device so it can negotiate the security restictions of the Insteon protocol and track the status of your Insteon devices. Used this way, the memory restrictions are virtually eliminated and features are less constrained by the interface itself. PowerHome will eventually support the PLM in order to gain access to the extended Insteon command set but this does not provide enough of an advantage at this time to offset the other problems being seen in the current PLM releases.
The reduction of the PLM output power seems significant to me. I have no major communications problems with a PLC but with a PLM the communication is HORRIBLE.
The workaround sugested on some forums is to plug an Accesslink into the PLM to act as a repeater. That only adds to the heat problem and may be why I locked up two in a matter of weeks.
The workaround sugested on some forums is to plug an Accesslink into the PLM to act as a repeater. That only adds to the heat problem and may be why I locked up two in a matter of weeks.
johnnynine
Active Member
Interesting, I thought the PLM was the solution to all the PLC's problems. The insteon PLC was one of the main reasons I stopped using insteon. Then when the PLM came out I was under the impression that it was much more reliable.
Firmware/Software wise maybe. They are working on a version with extended memory to try and alleviate the 417 link maximum capacity issue as well.
When they lowered the sensitivityand or output power the communications reliability went down (maybe not for everyone) and people started using the Accesspoint as a workaround. For me it was still not enough. The PLC works 99% of the itme I would say. The PLM was probably 70 % or so at best(I dont have hard numbers to back it up its a best guess).
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