Allen-Bradley 1756-CP3 RS232 Cable Logix SLC Programming

Product Architecture & Overview

The Allen-Bradley 1756-CP3 is a dedicated serial communication interface for the Logix and SLC controller families. This 3-meter (10-foot) programmer cable facilitates a point-to-point RS232 connection between a controller’s front-panel serial port and Data Terminal Equipment (DTE). Featuring a 90-degree female 9-pin D-shell connector for the controller side and a straight female 9-pin D-shell for the PC side, the 1756-CP3 ensures stable serial data transfer for logic configuration and online monitoring.

Oiltech Controls’s Insight

• The 1756-CP3 remains the industry standard for physical serial access to ControlLogix chassis.
• Engineered with superior shielding to prevent EMI interference during critical logic synchronization.
• Right-angle connector design is essential for closing cabinet doors during active monitoring.
• Directly supports high-speed serial baud rates required for RSLinx Classic configuration.
• Inquiries: info@oiltechcontrols.com | WhatsApp: +86 158 8020 0923

Core Technical Matrix

• Manufacturer: Rockwell Automation / Allen-Bradley
• Part Number: 1756-CP3
• Cable Interface: RS232 Serial (DB9 Female to DB9 Female)
• Cable Length: 3 Meters (10 Feet)
• Series Support: ControlLogix (Logix 5550+), SLC 5/03, 5/04, 5/05
• Connector Profile: 90-degree (Controller) / Straight (PC)
• Thermal Dissipation: 17.4 BTU per hour
• Net Weight: 0.293 kg (0.64 lbs)

Device Suitability & Interfacing

• Fully compatible with ControlLogix 1756-L55, L6x, and L7x series processors.
• Supports serial communication for SLC 500 modular controllers (SLC 5/03 and above).
• Interfaces with standard DB9 COM ports on industrial PCs or high-quality USB-to-RS232 converters.
• Optimized for use with Studio 5000 and RSLogix 500/5000 programming environments.

Logistics & Warranty Terms

• Warranty: 12-Month standard industrial warranty coverage.
• Dispatch Speed: Rapid shipping within 24-48 hours from order confirmation.
• Carrier Partners: Global express delivery through FedEx, UPS, and DHL.
• Quality Status: New & Original in factory-sealed packaging.

Purchasing & Selection Guide

• Verify the controller side requires a 9-pin D-shell; some CompactLogix units may require different mini-DIN cables.
• Select the 1756-CP3 for fixed 3-meter distances; ensure RS232 signal integrity for longer runs.
• If your laptop lacks a COM port, use a high-quality industrial USB-to-Serial adapter.
• Contact info@oiltechcontrols.com or +86 158 8020 0923 for bulk project pricing.

Professional FAQ (Field Experience)

• Why does the 1756-CP3 use a right-angle connector?
• It reduces physical strain on the controller’s serial port and allows for enclosure door clearance.
• Can this cable be used for DH-485 communication?
• No, the 1756-CP3 is strictly an RS232 null-modem style cable and does not support DH-485.
• What is the maximum baud rate supported by the 1756-CP3?
• It supports the full baud rate capability of the Logix serial port, typically up to 115.2 Kbps.
• Is it safe to leave the 1756-CP3 connected permanently?
• While possible, it is recommended for programming and diagnostic use only to prevent mechanical wear.
• How do I troubleshoot a “Failed to Browse” error in RSLinx?
• Ensure the “RS-232 DF1 Devices” driver is configured and use the “Auto-Configure” feature.

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