Danfoss VLT 6000 warning #34

[jtech1111]

I'm maintaining VFDs that that recently installed for energy saving purposes.
Recently an Alarm/Warning started blinking "Warning 34". according to the manual, HPFB communication fault (the serial communication card is not working).
I tried to reset and i aknowledged at the BAS computer but no avail.
any idea what caused it? How can i correct the problem? If i replace the communication card i'm not quite sure how to commission it.
Please help. Thanks

[controldude]

1:Does this drive have RS485 communication to your BAS/or Serial comm being used
2:What is the serial number some units have ribbon cable problems giving false alarms although that isn't the alarm I've been seeing

[jtech1111]

This VFD setup is controled remotely by Lonwatcher3 (Lonworks) program via series of routers to a DDC (Distech Control).
It's pretty neat though but too high tech and a little complicated.
This VFD is hooked up to a 450 ton chiller, this one control the chilled water pump. DDC control other stuff like the valves and dampers on AHUs.
VFD is 52.5 kva output.

Pardon my ignorance here dude, but i will double check to make sure. either RS485 0r serial comm.
as for ribbon cable prob. i'll check on this too.

thanks and please bear w/ me on this one.