38
Network Configuration
Section 2-2
cable alone. Use the following formulae to calculate the max. network length
based on the lengths of thick and thin cable in the line.
L
THICK
: Length of thick cable in the maximum network length
L
THIN
: Length of thin cable in the maximum network length
Example Calculation
L
THICK
+ L
THIN
= 175 m
≥
100 m
500 kbps not allowed
L
THICK
+ 2.5
×
L
THIN
= 250 m
≤
250 m
250 kbps OK
L
THICK
+ 5
×
L
THIN
= 375 m
≤
500 m
125 kbps OK
The results of the above formulae indicate that 250 kbps and 125 kbps can be
used as the baud rates for this configuration example.
Even when the above conditions are met, however, the current flowing
through the cables must not exceed the permissible current capacity. (Refer to
SECTION 3 Communications Power Supply Methods
.)
Applications Requiring
Thin Cable
Thin cable must be used in applications where space is restricted and thick
cable cannot be bent enough. In particular, use thin cable when wiring
devices mounted to DIN Track and the area between the DIN Tracks is limited.
In conclusion, we recommend the following usage:
Baud rate
Max. network length
500 kbps
L
THICK
+ L
THIN
≤
100 m
250 kbps
L
THICK
+ 2.5
×
L
THIN
≤
250 m
125 kbps
L
THICK
+ 5
×
L
THIN
≤
500 m
6 m
24 m
125 m
20 m
1 m
Max. network length
Terminal-block
Terminating Resistor
Node
Node
Node
Node
PS
Thick
Thin
Thin
Thin
Application
Cable type
Trunk line
Thick cable
Branch lines
Unrestricted spaces such as outside panels
Thick cable
Restricted spaces such as within panels
Thin cable
Sub-panel
Thin cable
Thin cable
DIN Track
Thick cable
Содержание DEVICENET -
Страница 1: ...DeviceNet Cat No W267 E1 11 OPERATION MANUAL...
Страница 2: ...DeviceNet Operation Manual Revised April 2008...
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Страница 41: ...20 Basic Operating Procedures Section 1 4...
Страница 107: ...86 Operational Checklist Section 2 6...
Страница 123: ...102 Step 3 Splitting the System into Multiple Power Supplies Section 3 6...
Страница 161: ...140 Index...