Rockwell Automation Allen-Bradley 842D, Руководство пользователя

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3-2 Configuring the DeviceNet Encoder DIP Switches
Setting the Node Address
The Node Address is set via the 6-pole DIP switch. The DIP switch
settings are binary starting with switch number 1 = (2
0
) and ending
with switch number 6 (= 2
5
).
0 = DIP switch is OFF
1 = DIP switch is ON
Setting the baud rate
The 3-pole DIP switch allows for setting the transmission baud rate.
X = don't care
0 = DIP switch is OFF
1 = DIP switch is ON
Bus termination
The recommended method for connecting DeviceNet products is to
run a “trunk line” with 120-ohm resistors connected at each end.
DeviceNet products are then connected as “drops” along the length of
the trunk line. In this configuration, the internal termination resistor
of the 842D should not be used and the bus termination DIP switches
should be in the OFF position.
When 842D encoders are connected in a “daisy chain” configuration,
the internal termination resistor may be used on the
end positions
only . In this configuration, only 842D(s) at either end of the network
should have their bus termination 2-pole DIP switches placed in the
ON position. Further details on termination resistors can be found in
publication DN-6.7.2
DeviceNet Cable System Planning and
Installation Manual.
DIP-1 DIP-2 DIP-3 DIP-4 DIP-5 DIP-6
Address
2
0
2
1
2
2
2
3
2
4
2
5
0 0 0 0 0 0 0
1 0 0 0 0 0 1
... ... ... ... ... ... ...
1 1 1 1 1 1 63
DIP-1 DIP-2 DIP-3 Baud rate
0 0 X 125 kBaud
1 0 X 250 kBaud
0 1 X 500 kBaud
1 1 X 125 kBaud
!
ATTENTION: If you do not use terminating resistors
as described here and in publication DN-6.7.2, the
DeviceNet system will
not operate properly.