PRODUCT INFORMATION
Product Overview
The Allen-Bradley 1771-IH is an 8-point PLC-5 Digital Input Module. It operates across a rated DC input voltage range of 24 to 50V DC. The hardware supports sinking input circuits for field sensors with sourcing load capability. It connects to field wiring using a removable 1771-WA wiring arm. The assembly mounts directly into any standard 1771 I/O chassis slot.
This module draws 74 mA of backplane current at 5V DC. It features 1500V AC RMS optical isolation between field circuits and the backplane logic. Nominal input current is 8.4 mA at 24V DC and 20 mA at 48V DC. The typical turn-on signal delay is 15 ms with a tolerance of 7 ms. The turn-off signal delay is typically 20 ms with a tolerance of 9 ms. Individual status indicators display the on and off conditions of all eight channels.
TECHNICAL DATA
Technical Specifications
| Parameter | Specification |
|---|
| Backplane Current | 74 Miliamperes |
|---|
| Category | PLCs |
|---|
| DC Operating Voltage | 24-50 Volts |
|---|
| GTIN | 10662468205532 |
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| Max DC Off-State Current | 0.7 Miliamperes |
|---|
| Model Status | Earlier Model |
|---|
| Module Type | Digital DC Input Module |
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| Mounting | Rack Mountable |
|---|
| Number of Inputs | 8 Inputs |
|---|
| Product Line | PLC 5 |
|---|
| Typical AC Signal Delay (Off) | 24 (+/- 10) ms |
|---|
| Typical DC Signal Delay (Off) | 20 (+/- 9) ms |
|---|
| Typical DC Signal Delay (On) | 15 (+/- 7) ms |
|---|
| Voltage Category | 10-60 Volts DC, Sink (Source Load) |
|---|
| Weight | 0.94 lbs (0.43 kg) |
|---|
| Wiring Arm | 1771-WA |
|---|
TECHNICAL INFORMATION
Features
- Provides eight discrete DC input channels in a single slot.
- Supports 24 to 50V DC nominal operating voltage levels.
- Offers 1500V AC RMS galvanic isolation between field inputs and logic.
- Includes red status indicator LEDs for each individual input point.
- Draws a low backplane current load of 74 mA at 5V DC.
TECHNICAL INFORMATION
Applications
- Sensing position from DC proximity switches and limit switches.
- Monitoring dry-contact status in industrial discrete manufacturing lines.
- Receiving digital state feedback in 1771 PLC-5 automation systems.
TECHNICAL INFORMATION
Connections / Interfaces
- Interfaces with field wiring through the 1771-WA swing-arm terminal strip.
- Plugs into backplane edge connectors inside standard 1771 I/O chassis.
TECHNICAL INFORMATION
Installation Guidelines
- Insert the module into an unpowered 1771 I/O chassis slot.
- Secure the module firmly using chassis card guides and locking latches.
- Attach the 1771-WA wiring arm to the chassis pivot post.
- Terminate field cables according to sinking DC input wiring diagrams.
TECHNICAL INFORMATION
Configuration Guidelines
- Configure input addressing in the PLC-5 processor I/O image table.
- Ensure signal response times accommodate the typical 15 ms turn-on delay.
TECHNICAL INFORMATION
Compatibility
- Mounts into Allen-Bradley 1771 I/O chassis assemblies.
- Connects to field wiring via the 1771-WA wiring arm.
TECHNICAL INFORMATION
Lifecycle / Replacement Information
- Classified as an earlier model PLC-5 component.
- Replaced through existing spare stock or refurbished supply channels.
TECHNICAL RESOURCES
Documentation
COMPATIBILITY
Compatibility & Replacement
COMPATIBLE MODELSMounts into Allen-Bradley 1771 I/O chassis assemblies. Connects to field wiring via the 1771-WA wiring arm.
Verify compatibility against the exact Part Number, revision and manufacturer documentation before ordering.
PART VERIFICATION
Before You Order
Industrial automation parts can share similar model names, suffixes and revisions. Confirm the complete manufacturer Part Number before purchase.
01Check Part NumberMatch the complete ordering code on the existing unit.
02Confirm RevisionCheck suffix, hardware or firmware when applicable.
03Send a Label PhotoWe can review a clear label photo when identification is uncertain.
ORDERING PROCESS
From RFQ to Dispatch
1Submit Part Number2Verify Product Identity3Confirm Stock & Condition4Issue Quotation5Dispatch & Tracking
PRODUCT FAQ
Frequently Asked Questions
What is the backplane current draw for the 1771-IH?
The 1771-IH module draws 74 mA at 5V DC from the 1771 chassis backplane power supply.
Which wiring arm is compatible with the Allen-Bradley 1771-IH?
Field wiring connects via the 1771-WA wiring arm, allowing module replacement without unwiring field terminals.
What is the typical market reference price for the 1771-IH?
Observed market reference pricing is approximately $129.00 USD for refurbished condition. Figures are indicative market reference pricing only and are not a final quotation.
