7.1.3 RS-485 Bus Termination
Use the terminator dip switch on the main control board of the adjustable
frequency drive to terminate the RS-485 bus.
NOTE!
The factory setting for the dip switch is OFF.
Terminator Switch Factory Setting
7.1.4 EMC Precautions
The following EMC precautions are recommended in order to achieve interference-free operation of the RS-485 network.
Relevant national and local regulations, for example regarding protective ground connection, must be observed. The RS-485 communication cable must
be kept away from motor and brake resistor cables to avoid coupling of high frequency noise from one cable to another. Normally a distance of 200 mm
(8 inches) is sufficient, but keeping the greatest possible distance between the cables is generally recommended, especially where cables run in parallel
over long distances. When crossing is unavoidable, the RS-485 cable must cross motor and brake resistor cables at an angle of 90 degrees.
VLT HVAC Low Harmonic Drive Instruction
Manual
7 RS-485 Installation and Set-up
MG.16.A1.22 - VLT
®
is a registered Danfoss trademark
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