Grounding Shielded Control Cables; Dip Switches; Serial Communication - Danfoss vlt fcd 302 Operating Instructions Manual

Installation

2.4.12 Grounding Shielded Control Cables

2 2
See Illustration 2.11 for details.
A A . Correct grounding
Secure control and serial communication cables with
grounding clamps provided at both ends to ensure best
possible electrical contact.
B. 50/60Hz ground loops
With very long control cables, ground loops may occur. To
eliminate ground loops, connect one end of the screen to
ground with a 10nF capacitor (keeping leads short).
C. Serial communication
To eliminate low-frequency noise between frequency
converters, connect one end of the screen to terminal 61.
This terminal is connected to ground via an internal RC link.
Use twisted-pair cables to reduce interference between
conductors.

2.4.13 DIP Switches

•
Analog input terminals 53 and 54 can select for
either voltage (0-10V) or current (0-20mA) input
signals
•
Set switches S201 (terminal 53) and S202 (terminal
54) to select the signal type. ON is for current, OFF
for voltage
•
Terminal 53 default is for a speed reference in open
loop
•
Terminal 54 default is for a feedback signal in
closed loop
20
inverter.ru (812) 702-47-50
PLC etc.
FC
PLC etc.
FC
b
10nF
FC FC
69
68
61
c
MG.04.F2.02 - VLT is a registered Danfoss trademark
VLT Decentral Drive FCD 302 Operating Instructions
3
Illustration 2.11 Location of DIP Switches
1 S201 - terminal 53
2 S202 - terminal 54
3 S801 - standard bus termination
4 Profibus termination
5 Profibus address
NOTE
Switches 4 and 5 are only valid for units fitted with Profibus.
a

2.4.14 Serial Communication

Connect RS-485 serial communication wiring to terminals
(+)68 and (-)69.
•
•
•
•
•
•
1 2
4 5
Switch S801 (BUS TER.) can be used to enable
termination on the RS-485 port (terminals 68 and
69). See Illustration 2.11 above.
Shielded serial communication cable is
recommended
See 2.4.12 Grounding Shielded Control Cables for
proper grounding
Two communication protocols are internal to the
frequency converter
•
Danfoss FC
•
Modbus RTU
For basic serial communication set up, select the
following
•
Protocol type in 8-30 Protocol
•
Frequency converter address in
8-31 Address
•
Baud rate in 8-32 FC Port Baud Rate
Functions can be programmed remotely using the
protocol software and RS-485 connection or in
parameter. group 8-** Communications and
Options