NOTE:
When applying power to the CPU (DL250–1/260) and local expansion bases, make sure the
expansion bases power up at the same time or before the CPU base. Expansion bases that power up after
the CPU base will not be recognized by the CPU. (See chapter 3 Initialization Process timing
specifications).
DL250–1 Local Expansion System
The D2–250–1 supports local expansion up to three total bases ( one CPU base + two local
expansion bases) and up to a maximum of 768 total I/O points. An example local expansion
system is shown below. All local and expansion I/O points are updated on every CPU scan.
No specialty modules can be located in the expansion bases (refer to the Module Placement
Table earlier in this chapter for restrictions).
• The CPU base can be located at any base position in the expansion system.
• All discrete and analog modules are supported in the expansion bases. Specialty modules are
not supported in the expansion bases.
• The D2–CMs do not have to be in successive numerical order, however, the numerical
rotary selection determines the X and Y addressing order. The CPU will recognize the local
and expansion I/O on power–up. Do not duplicate numerical selections.
• The TERM (termination) switch on the two endmost D2–EMs must be in the ON
position. The other D2–EMs in between should be in the OFF position.
• Use the D2–EXCBL–1 or equivalent cable to connect the D2–EMs together. Either of the
RJ45 ports (labelled A and B) on the D2–EM can be used to connect one base to another.
DL205 User Manual, 4th Edition, Rev. B
4–14
Chapter 4: System Design and Configuration
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
D2–EM Termination
Switch Settings
D2–CM Expansion
Base Number Selection
D2–250–1
CPU
Use D2–EXCBL–1 (1m)
(Category 5 straight–
through cable) to connect
the D2-EMs together.
.
I/O addressing #1
I/O addressing #2
I/O addressing #3
30m (98ft.) max. cable length
Note: Do not use
Ethernet hubs to
connect the local
expansion system
together.
