Danfoss VLT HVAC Drive FC 100 Series, Руководство по конструкции

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7.1.2 Adjustable Frequency Drive Hardware
Setup
Use the terminator dip switch on the main control board
of the Adjustable frequency drive to terminate the RS-485
bus.
1 2
S801
ON
130BA272.11
Figure 7.3 Terminator Switch Factory Setting
The factory setting for the dip switch is OFF.
7.1.3 Adjustable Frequency Drive
Parameter Settings for Modbus
Communication
The following parameters apply to the RS-485 interface
(FC-port):
Parameter Function
8-30 Protocol Select the application protocol to run on
the RS-485 interface
8-31 Address Set the node address. Note: The address
range depends on the protocol selected in
8-30 Protocol
8-32 Baud Rate Set the baud rate. Note: The default baud
rate depends on the protocol selected in
8-30 Protocol
8-33 Parity / Stop
Bits Set the parity and number of stop bits.
Note: The default selection depends on the
protocol selected in
8-30 Protocol
8-35 Minimum
Response Delay Specify a minimum delay time between
receiving a request and transmitting a
response. This can be used for overcoming
modem turnaround delays.
8-36 Maximum
Response Delay Specify a maximum delay time between
transmitting a request and receiving a
response.
8-37 Maximum
Inter-Char Delay Specify a maximum delay time between
two received bytes to ensure timeout if
transmission is interrupted.
Table 7.2
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 200mm (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.
Ser
ial c
om. bus cable
Brake resistor
Min. 200mm
90° crossing
130BA080.10
Figure 7.4
RS-485 Installation and Set...
VLT
®
HVAC Drive Design Guide
7-2 MG11BB22 - VLT
®
is a registered Danfoss trademark
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