Danfoss VLT AQUA Instruction Manual page 103

VLT AQUA High Power Instruction Manual
4.1.12 RS-485 Bus Connection
One or more adjustable frequency drives can be connected to a controller
(or master) using the standard RS-485 interface. Terminal 68 is connec-
ted to the P signal (TX+, RX+), while terminal 69 is connected to the N
signal (TX-, RX-).
If more than one adjustable frequency drive is connected to a master,
use parallel connections.
In order to avoid potential equalizing currents in the screen, ground the cable screen via terminal 61, which is connected to the frame via an RC link.
Bus termination
The RS-485 bus must be terminated by a resistor network at both ends. If the drive is the first or the last device in the RS-485 loop, set the switch S801
on the control card to ON.
For more information, see the paragraph
4.1.13 How to Connect a PC to the Adjustable Frequency Drive
To control or program the adjustable frequency drive from a PC, install the PC-based Configuration Tool MCT 10.
The PC is connected via a standard (host/device) USB cable, or via the RS-485 interface as shown in the
of misc. connections .
NOTE!
The USB connection is galvanically isolated from the supply voltage (PELV) and other high-voltage terminals. The USB connection is
connected to protection ground on the adjustable frequency drive. Use only isolated laptop for PC connection to the USB connector on
the adjustable frequency drive.
Figure 4.10: For control cable connections, see section on
Switches S201, S202, and S801 .
Control Terminals
®
MG.20.P3.22 - VLT is a registered Danfoss trademark
4 How to operate the adjustable frequency
Figure 4.9: Connection example.
Design Guide, chapter How to Install > Installation
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drive
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