I'm building a BMS based on NAE and FXs talking to each other via LON. I managed to connect FXs to NAE and download points for each FX which was quite a struggle Now I can read all the output NVs through NAE, but I can't read any input NVs and therefore change their values.
In the FX builder you can put the point on the network as a permanent point or as a volatile point. Permanent means that the value is stored in the memory of the FX and volatile means that the value is gone when the power supply is gone, right?
To protect the set points and all that, the FX programmer put all the points on the network as permanent points, what seems to be resonable.
Anyway, I took one FX program, changed some points into volatile points, downloaded it into FX, extracted the xif file and attached it to NAE's Lon Trunk and after all that I was able to see the points that I changed into volatile points.
And here's my question: is it the only way of having the ability to change the value of a point? It just has to be a volatile point?
I called a JCI guy with that question and he answered yes, but to be honest, I don't trust him
If it's true, then let suppose the NAE breaks down and the electricity goes down for a moment - all the FXs lose their set points and the AHU under them won't work properly if you start them manually.
Thanks for your time