Technical data

ManualsBrandsAllen-Bradley ManualsAdapter1794ASB Series B

Publication 1794-2.1 - January 2000

FLEX I/O and FLEX Integra Product Data

24V dc Remote I/O Adapter (up to 8 modules) Cat. No. 1794-ASB/C & /D 15

24V dc Remote I/O Adapter (up to 8 modules) Cat. No. 1794-ASB/C & /D

Wiring

The series D adapter can communicate with FLEX Integra analog

modules.

1. Connect the remote I/O cable to the removable remote I/O

connector.

2. Connect +24V dc input to the left side of the lower connector,

terminal E.

3. Connect 24V common to the left side of the upper connector,

terminal D.

4. Connections G and F are used to pass 24V dc power (G) and 24V

common (F) to the next module in the series (if required).

5. Make wiring connections as described in the installation

instructions included with the module that mounts on your

terminal base unit.

The 1794-ASB adapter module can interface a maximum of 8 I/O

modules. This adapter can be used in the mode that requires a unique

location address for each I/O module and can also be used in a mode

that allows duplicate addressing of I/O modules.

Duplicate addressing of I/O modules allows the maximum amount of

I/O in a system for a given amount of I/O image area. An input

module can have the same location address as an output module

because they complement each other. The input module uses only the

input image area corresponding to the address. The output module

uses only the output image area corresponding to the address.

ATTENTION

When connecting wiring, torque terminal

screws D, E, F, and G to 7-9 inch-pounds.

Description of Modes

Addressing

Type

Module Placement Rules Legal Module

Placements

Standard • 8 terminal bases per adapter

• Each terminal base

represents 1 I/O group

• Any module in any slot

Compact

16-point

addressing

• 8 terminal bases per adapter

• Each module represents 1/2

of an I/O group

• 2 modules represent 1 I/O

group

• 8 modules = 1/2 I/O rack

• A 16-point input module and a

16-point output module in an

I/O group

Compact

8-point

addressing

digital modules

• 8 terminal bases per adapter

• Each module represents 1/4

of an I/O group

• 4 modules represent 1 I/O

group

• Two 8-point input modules

and two 8-point output

modules in an I/O group

• Module type must alternate

within an I/O group: input,

output, etc.

COM

24V

1SH2

30228

Description of Modes (continued)

Compact

8-point

addressing

analog

modules

• 8 terminal bases per adapter

• Each module and adjacent

empty base represents 1/2 of

an I/O group

• Two block transfer modules

and their adjacent empty base

= 1 I/O group - An empty slot

must accompany each block

transfer module in 8-point

compact addressing

Complementary

16-point

addressing

• 8 terminal bases per adapter

• 2 modules, 1 in primary, and

1 in complement represent 1

I/O group

• Any module in any I/O position

of the primary chassis, input

modules complemented by

output modules, analog

modules complemented by

analog modules or empty base

Complementary

8-point

addressing

• 8 terminal bases per adapter

• 4 modules, 2 in the primary

and 2 in the complement,

represents 1 I/O group

• 2 inputs in a group

complemented by 2 outputs

• 2 outputs in a group

complemented by 2 inputs

• 2 block transfer modules

complemented by 2 empty

slots

• 1 block transfer module and 1

input in a group

complemented by 1 empty slot

and 1 output module

Specifications - 1794-ASB/C & /D

The 1794-ASB/C & /D adapter cannot be used with PLC-2 processors.

I/O Capacity 8 modules

Power Supply Note: In order to comply with CE Low Voltage

Directives, you must use a Safety Extra Low Voltage

(SELV) or a Protected Extra Low Voltage (PELV)

power supply to power this adapter.

Input Voltage Rating 24V dc nominal

Input Voltage Range 19.2V to 31.2V dc (includes 5% ac ripple)

Communication Rate 57.6, 115.2, 230.4k bit/s

Indicators Adapter active - green

Adapter fault - red, Local fault - red

Flexbus Output Current 640mA maximum

Isolation Voltage 500V ac between user power and flexbus

Power Consumption 450mA maximum from external 24V supply

Power Dissipation 4.6W maximum @ 31.2V dc

Thermal Dissipation 15.7 BTU/hr @ 31.2V dc

General Specifications

Dimensions HxWxD 87mm x 68mm x 69mm (3.4in x 2.7in x 2.7in)

Environmental Conditions

Operational Temperature

Storage Temperature

Relative Humidity

Shock Operating

Non-operating

Vibration

0 to 55

C (32 to 131

-40 to 85

C (-40 to 185

5 to 95% noncondensing

30g peak acceleration, 11(±1)ms pulse width

50g peak acceleration, 11(±1)ms pulse width

Tested 5g @ 10-500Hz per IEC 68-2-6

Remote I/O Cable Belden 9463 or equivalent as specified in A-B

Approved Vendor List, publication ICCG-2.2

A-B pin connector part no. 942029-03

Power Conductors

Wire Size