Xiamen Xingruijia Import and Export Co., Ltd. has been specializing in the sales of industrial control equipment spare parts for 20 years. For more ABB models, please refer to the product list . If you need other brands or models, please contact us. We have a variety of brands and models in stock, and we can purchase difficult to order models for you. We look forward to your inquiry!!!
First hand source//affordable price//Spot inventory!
•Shipping Port: Xiamen
•Manager: Rhonda
•E-mail: sales7@saulplc.com
•Tel/WhatsApp/Wechat: + 86-15359273796
•Ship to you via Fedex/DHL/TNT/UPS/EMS
•Package: Original packing with cartons
ABB 1784-KT
The ABB 1784-KT is actually an Allen-Bradley (Rockwell Automation) legacy communication interface module, not an ABB-developed product. It is an ISA-bus communication card designed to allow industrial computers, programming terminals, and workstations to communicate with Allen-Bradley PLC systems through Data Highway Plus (DH+) and PLC serial networks.
The module was widely used in older PLC-2, PLC-3, and PLC-5 automation systems as a PC-side communication interface before modern PCI, Ethernet, and USB communication adapters became common.
2. Product Parameters
| Parameter |
Specification |
| Product Type |
Communication Interface Module |
| Manufacturer |
Allen-Bradley / Rockwell Automation |
| Model |
1784-KT |
| Bus Interface |
ISA 8-bit / 16-bit expansion slot |
| Network Interface |
Data Highway Plus (DH+) |
| Supported PLC Networks |
PLC-2 Serial, PLC-3 Serial, DH+ |
| External Connector |
62-pin D-shell connector |
| DH+ Communication Speed |
57.6 kbps |
| PLC Serial Speed |
9600 baud / 19.2 kbps |
| Power Supply |
+5 VDC @ 0.4 A; ±12 VDC @ 0.04 A |
| Power Consumption |
Approx. 2 W (+5 V), 0.48 W (±12 V) |
| Operating Temperature |
0…55 °C |
| Humidity |
5…95% RH non-condensing |
3. Core Functions
3.1 DH+ Network Communication
The primary function of the 1784-KT is providing a computer-to-PLC communication bridge through the Allen-Bradley Data Highway Plus network.
Typical communication tasks include:
- PLC program upload/download
- Online PLC monitoring
- Data table access
- HMI/SCADA communication
- PLC diagnostics
- Remote controller access
The card allows a computer to operate as an active node on a DH+ network.
3.2 PLC Controller Connectivity
The module supports communication with legacy Allen-Bradley controller families:
- PLC-2
- PLC-3
- PLC-5
- Related industrial terminals and workstations
3.3 Industrial Programming Interface
Before modern communication adapters such as Ethernet/IP modules, the 1784-KT was commonly used for:
- PLC maintenance stations
- Factory programming terminals
- Engineering workstations
- Industrial PCs running DOS/Windows-based programming software
4. Design Features
4.1 ISA Expansion Card Architecture
The 1784-KT uses a classic ISA computer expansion design:
- Direct installation inside industrial PCs
- Hardware interrupt configuration
- Memory address selection
- Low-level communication control
This design matched the computer platforms commonly used in industrial automation systems of the 1980s and 1990s.
4.2 Hardware Configuration
Configuration is performed through onboard settings:
- Memory address selection
- Interrupt selection
- Communication parameters
Typical supported interrupts include:
4.3 High Reliability Industrial Design
Features include:
- Industrial temperature capability
- Robust communication circuitry
- Dedicated hardware interface
- Long-term operation in factory environments
5. Hardware Composition
The 1784-KT consists of several major sections:
1. ISA Bus Interface
Responsible for:
- PC motherboard communication
- Memory mapping
- Interrupt handling
- Data transfer
2. Communication Controller Circuit
Handles:
- DH+ protocol processing
- PLC communication timing
- Serial communication management
3. External Communication Port
A 62-pin D-shell connector provides connection to:
- DH+ network cabling
- PLC communication cables
- Allen-Bradley communication accessories
4. Configuration Hardware
Includes:
- DIP switches
- Address selection circuits
- Interrupt configuration components
6. Typical Applications
6.1 PLC Programming Stations
Used with engineering computers for:
- PLC logic editing
- Online troubleshooting
- Controller maintenance
6.2 Factory Automation Systems
Commonly found in:
- Automotive manufacturing
- Packaging machinery
- Process plants
- Material handling systems
6.3 Legacy System Migration
Today, remaining 1784-KT cards are mainly used for:
- Maintaining old PLC-5 installations
- Supporting legacy production lines
- Data recovery from obsolete automation systems
7. Maintenance Considerations
Hardware Maintenance
Recommended checks:
- Inspect ISA connector contacts
- Check oxidation on edge connectors
- Verify cable condition
- Confirm correct DIP switch configuration
Communication Troubleshooting
Common problems:
No PLC Communication
Possible causes:
- Incorrect DH+ node address
- Wrong IRQ setting
- Memory conflict
- Damaged communication cable
Intermittent Communication
Possible causes:
- Aging ISA hardware
- Electrical noise
- Poor grounding
- Network termination issues
Storage Recommendations
Because the module uses CMOS-sensitive components:
- Use anti-static protection
- Store in ESD-safe packaging
- Avoid touching connector pins directly
8. Comprehensive Evaluation
The Allen-Bradley 1784-KT represents an important generation of industrial communication hardware. Its strengths include:
✅ Reliable DH+ connectivity
✅ Direct PLC programming capability
✅ Proven industrial durability
✅ Compatibility with legacy PLC systems
Sweden 
.jpg)
.jpg)
