A-B 1747-ASB Module Overview Remote I/O Adapter Module

1747-ASB Module Overview

The 1747-ASB module is an SLC 500 single-slot, RIO communication link module. It

occupies the first slot (slot 0) of a 1746 remote chassis, where the SLC processor

normally resides.

The 1747-ASB module is an adapter, or slave, on the RIO link, and the master of the

remote chassis and remote expansion chassis in which it is installed. Remote

expansion chassis are optional. The module acts as a gateway between the scanner

and the I/O modules residing in the remote chassis and remote expansion chassis.

It maps the image of the I/O modules in its remote chassis and remote expansion

chassis directly to the SLC or PLC processor image.

Output data is sent from the scanner of either the SLC or PLC local chassis to the

1747-ASB module across the RIO link. This data is automatically transferred to the

output modules across the chassis backplane by the 1747-ASB module. Inputs from

the input modules are collected via the backplane by the 1747-ASB module and

sent back to the scanner across the RIO link. No user programming of the 1747-ASB

module is necessary.

Hardware Features

Required Tools and Equipment

Have the following tools and equipment ready:

• medium blade screwdriver

• (2) 1/2 watt terminating resistors (See page 18 for correct size.)

• an adequate length of RIO communication cable (Belden™ 9463) for your

specific application. (See page 18 for maximum cable distances.)

Determining System Power Requirements

Review the power requirements of your system to ensure that the chassis supports

placement of the 1747-ASB module. The adapter consumes 600 mA at 5V dc. For a

detailed list of device load currents, refer to the SLC 500 Fixed Hardware Style

Installation and Operation Manual, publication number 1747-6.21; the SLC 500

Modular Hardware Style User Manual, publication number 1747-UM011, or the

appropriate Technical Data sheet.

Slot Addressing

Slot Numbering

The 1747-ASB module is capable of controlling 30 slots. When expansion chassis

are used, the 1747-ASB module treats all of the I/O modules as if they are installed

in a single chassis.

The remote chassis and remote expansion chassis slots are numbered from 0 to 30.

The 1747-ASB module must reside in slot 0. Slots numbered 31 and above cannot

be used.

IMPORTANT Installing modules in slot 31 or above results in a module error.

Addressing I/O Modules

SLC and PLC processors address the I/O modules residing in the chassis by logical

rack and logical group. Slot addressing refers to how each chassis slot is assigned a

specific amount of the 1747-ASB module image. The amount depends on which

type of slot addressing you choose; 2-slot, 1-slot, and 1/2-slot addressing is

available, as shown below.

IMPORTANT Due to SLC and PLC addressing differences, when the 1747-ASB

module is used with an SLC processor, the image bit numbers are

0 to 7, 8 to 15 decimal. When the 1747-ASB module is used with

a PLC processor, the image bit numbers are 0 to 7, 10 to 17 octal.