I have a Nilan Compact-P heating system in my home and it has a USB connector. When I plug it in my Windows Laptop automatically the driver for "lmc 300" is installed and a COM Port opens up.

Nilan Compact P

This is the panel where I can control temperatures and read the info from (but can't export) Panel of the heating system

My goal is to talk to the controller to read information about the heating system like Temperatures, status (currently heating or not), etc..

What I know by now:

  • A technician of the company said they use a software called "loader multitool" to read the data via USB. I didn't find any software by this (pretty generic) name via Google. Has anyone of you heard of it?
  • The Engineer also talked about some "motus module" but that also doesn't bring up many answers on Google
  • I tried talking to the Heating system via the COM Port and Putty. No reply whatsoever but then again I don't even know its baud rate

Has anyone of you heard of this LMC and knows how to talk to it?


The "motus module" that the engineer was talking about, is probably a "modbus module". Modbus is a protocol normally used on top the RS485 serial bus.

The LMC 300 controller communicates with the control panel using RS485. I think you will have more luck using this interface instead of the USB interface as both Modbus and RS485 are industry standards and well documented. The data on the USB interface might be very hard do decode.

Regarding the LMC 300, I have a theory that it also goes by the name LMC 320 - or maybe that's a 2nd generation of the same product - in any case, I think the information you can read online about how to communicate with the LMC 320 also applies to the LMC 300.

LMC 320 User Manual (page 48+49 details how to connect a RS485 device): https://www.manualslib.com/download/952626/Lodam-Lmc-320.html

I found this video a good resource to understand how RS485 works: https://www.youtube.com/watch?v=9NJVs3_g_PY&t=633s

You can read more about the Modbus data protocol here: http://www.simplymodbus.ca/FAQ.htm

|improve this answer|||||
  • \$\begingroup\$ Awesome pointers, thanks! I am still not at my goal but you helped me quite a bit \$\endgroup\$ – Christian May 20 '18 at 21:19

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.