VLT® 7000 Booster
Installation
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Switches 1-4
The dipswitch is located on the control card. It is used
for serial communication and external DC supply.
The switching position shown is the factory setting.
Switch 1 has no function.
Switches 2 and 3 are used for terminating an RS-485
interface to the serial communication bus
NB!:
When the frequency converter is the first or
last device on the serial communication bus,
switches 2 and 3 must be ON in that designated
VLT. Any other VLTs on the serial communication bus
must have switches 2 and 3 set to OFF.
NB!:
Please note that when Switch 4 is in position
"OFF," the external 24 V DC supply is galvanically
isolated from the frequency converter.
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Bus connection
The serial bus connection in accordance with the RS
485 (2-conductor) norm is connected to terminals
68/69 of the frequency converter (signals P and N).
Signal P is the positive potential (TX+,RX+), while
signal N is the negative potential (TX-,RX-).
If more than one frequency converter is to be connected
to a given master, use parallel connections.
In order to avoid potential equalizing currents in the
screen, the cable screen can be earthed via terminal
61, which is connected to the frame via an RC-link.
MG.70.A1.02 - VLT is a registered Danfoss trademark
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