A-B 1788-MCHKR Communication Module

Allen-Bradley 1788-MCHKR Communication Module / Diagnostic Tool

 

 

The Allen-Bradley 1788-MCHKR is not a PLC communication module, but a portable industrial network diagnostic tool (Network Media Checker). It is used to test and verify communication cables and network wiring integrity in industrial automation systems.

It is mainly used for troubleshooting ControlNet, DeviceNet, DH+/RIO, and Ethernet cabling.

Key Specifications

• Model: 1788-MCHKR
• Brand: Allen-Bradley (Rockwell Automation)
• Product Type: Network Media Checker / Diagnostic Tool
• Supported Media:
  • ControlNet
  • DeviceNet
  • DH+/RIO
  • Ethernet (RJ45)
• Connectors:
  • RJ45 Ethernet port
  • DB9 serial-style connector
• Display:
  • LCD screen (2-line text display)
• Power Supply:
  • Battery powered (AA batteries)
• Function Type:
  • Cable tester / network analyzer

What it does (simple explanation)

Cable / Network wiring
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1788-MCHKR tester
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Displays results:

• Open circuit
• Short circuit
• Cable length
• Wiring errors
• Signal integrity issues

It helps engineers quickly check whether communication problems come from:

• Bad cables
• Wrong wiring
• Network noise
• Connector faults

Main Functions

• Cable fault detection (open/short)
• Wiring verification (pin-to-pin test)
• Cable length estimation
• Network media troubleshooting
• Supports multiple Allen-Bradley industrial networks

Key Features

• Portable handheld design
• LCD display with simple menu operation
• Multi-network compatibility (legacy AB systems)
• DB9 + RJ45 interface support
• Fast field diagnostics
• Battery powered for maintenance use

Important Clarification

Many sellers mistakenly list this as a “communication module”, but technically:

• ❌ Not a PLC module
• ❌ Not an Ethernet/IP communication adapter
• ❌ Not a ControlLogix/CompactLogix plug-in card
• ✔ It is a network diagnostic tester (maintenance tool)

Applications

• Factory network troubleshooting
• PLC communication cable testing
• Commissioning ControlNet / DeviceNet systems
• Maintenance of legacy Allen-Bradley networks
• Electrical cabinet wiring checks