Rockwell Automation 1791-IOBB USER MANUAL - Manual (Page 8)

Chapter
2
2Ć1
Introducing Block I/O
In this chapter you will learn what block I/O is, and its features, and how
it functions.
Block I/O consists of small, self–contained remote I/O devices complete
with power supply, programmable controller interface, input/output
connections and signal conditioning circuitry.
Two types of block I/O are available. The 1791–IOBA has 8 inputs and 8
outputs; the 1791–IOBB has 10 inputs and 6 outputs. In all other aspects,
they are identical.
The blocks are compatible with PLC–2, PLC–3, and PLC–5 family
programmable controllers, and the SLC 500 modular controllers. When
used with PLC–2 family programmable controllers, a sub I/O scanner
module (cat. no. 1771–SN) or remote I/O scanner module (cat. no.
1772–SD2) is used to communicate with the blocks. When used with
PLC–3 and PLC–5 family programmable controllers, they can be
connected directly to the controller, a scanner module, or through a remote
I/O adapter module. When used with SLC 500 controllers, a 1747–DSN
scanner (or the 1747–SN Remote I/O scanner) is used to communicate
with the blocks.
Physical features of the block I/O are shown in Figure 2.1.
Figure 2.1
Major Features of the Block I/O Module (1791-IOBA shown)
OUTPUT
INPUT
COMM POWER
Removable Remote I/O Link Connector
Communication LED Power LED Status Indicators Switch Assemblies
Removable Input/Output Connector
DH-485 Port
10825-I
Chapter Objectives
General Description