Here's a newbie question:  I have just acquired an ISY-499i and need to get an Insteon PLM. There is a serial version and a USB version.  Does it matter which one I get.  That port is irrelevant to the ISY device, right?

You need the serial version.   And at the moment they are out of stock everywhere.  Rumor has it the first of the year they should be back, but I've not seen that offically posted anywhere.

10 minutes ago, gray88 said:

Here's a newbie question:  I have just acquired an ISY-499i and need to get an Insteon PLM. There is a serial version and a USB version.  Does it matter which one I get.  That port is irrelevant to the ISY device, right?

The ISY requires the serial version.  Currently the PLM is on back order from Smarthome, you may have to wait until the end of December or January before they become available. It's also possible that an updated version of the PLM may be what's back ordered.

This is what you'll need:

Serial Modem Interface | HouseLinc Compatible |Smarthome

 

 

Thanks - glad I asked.

I've gotten my last couple of PLMs from SmartEnit.  They are functionally equivalent to the old 2412S.  Con is that it's not dual band.  Pro is you can power your ISY through it, thus no need for a wall wart.  I don't know if they are still in stock, but I didn't see any out of stock notice on their website.

You're better off waiting. The newer PLMs have updated firmware, updated RS232 interface,, updated capacitors, and increased memory.