Installation Of Misc. Connections - Danfoss VLT Series Design Manual

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VLT HVAC Drive Design Guide

5.5. Installation of misc. connections

5.5.1. RS 485 Bus Connection
One or more frequency converters can be con-
nected to a control (or master) using the
RS485 standardized interface. Terminal 68 is
connected to the P signal (TX+, RX+), while
terminal 69 is connected to the N signal
(TX-,RX-).
If more than one frequency converter is con-
nected to a master, use parallel connections.
In order to avoid potential equalizing currents in the screen, earth the cable screen via terminal
61, which is connected to the frame via an RC-link.
Bus termination
The RS485 bus must be terminated by a resistor network at both ends. For this purpose, set switch
S801 on the control card for "ON".
For more information, see the paragraph
5.5.2. How to Connect a PC to the FC 100
To control or program the frequency converter from a PC, install the MCT 10 Set-up Software.
The PC is connected via a standard (host/device) USB cable, or via the RS-485 interface as shown
in the FC 100 Design Guide chapter
NB!
Communication protocol must be set to FC MC par. 8-30.
How to Install > Installation of misc.
NB!
The USB connection is galvanically isolated from the supply voltage (PELV) and other
high-voltage terminals. The USB connection is connected to protection earth on the
frequency converter. Use only isolated laptop as PC connection to the USB connector
on the VLT HVAC Drive.
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MG.11.B2.02 - VLT is a registered Danfoss trademark
Switches S201, S202, and S801
5. How to Install
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connections.
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