There are three situations about LED status:
1. Always green: That means you power on this module.
2. Extinguish: Data is transmitted from RS-232 to RS-422/485.
3. Momentary red: Data is transmitted from RS-422/485 to RS-232.
LED is:
green: when you search RS-485 network through ADAM-4520/4522,
orange: (green and red) when you get something from RS-485 network.
