How to check RS485 signal with Multimeter True RMS - Video 2 (2nd video)

Below description same as in Video 1 Normally whenever we use RS485 to control any device like Lighting or Blinds SDN like Somfy, If we connect to a controller like Crestron CP4/CP3 COM Port 1 Which has the options in program in SW to use as RS232 or RS485 The Baudrate and other parameters should match with the devices to control. If it’s worked then it’s Good, If it’s doesn’t work We need to start where is the Problem 1. Parameters not correct in Port Configuration SW Crestron. 2. Devices may not have power at all. 3. +D and -D including common wire’s not connected to the right terminal. Procedure:- You can send control signals like On/Off lights or up / Down in case of blinds Accordingly you should see the activity on you multimeter AC(in real these are square pulses ) Signal level 1.2 V to .8V Across +D and -D Multimeter used/ You can use similar Fluke - 112 True RMS Meter switch selection: AC Range: 10 Volt’s Terminal used: Common and Positive (Red &Black)