Purchase now: Allen Bradley 1747-CP3 RS-232 Programming Cable
Purchase now: Atlantechdrives provides you the 1747-CP3, the universally recognized and absolutely essential RS-232 serial programming cable for the Allen Bradley SLC 500 platform. This 3-meter (10-foot) cable connects your engineering laptop directly to the Channel 0 serial port of SLC 5/03, 5/04, and 5/05 processors, as well as CompactLogix and MicroLogix controllers (with the appropriate adapter). It allows you to use RSLogix 500 and RSLinx software to download logic programs, perform online edits, upload backups, and monitor live machine data. Engineered with a specialized «Null Modem» internal crossover, the 1747-CP3 is the required physical link for all DF1 full-duplex communication protocols in the Rockwell Automation ecosystem.
Technical Specifications of the 1747-CP3
The 1747-CP3 is not a standard straight-through serial cable. It is factory-molded with a specific crossover wiring configuration (Pin 2 to 3, Pin 3 to 2, Pin 5 to 5) that allows two DTE (Data Terminal Equipment) devices to communicate. It features a highly convenient right-angle connector on the PLC end.
- Part Number: 1747-CP3
- Component Type: PC to PLC Programming Cable
- Protocol Compatibility: RS-232, DF1 Full-Duplex, DH-485 via RS-232
- Connectors: 9-Pin D-Sub Female to 9-Pin D-Sub Female
- Design Feature: Right-angle 90-degree head on the PLC side
- Length: 3.0 Meters (10.0 Feet)
- Internal Wiring: Null Modem crossover
Expert Tips: The Importance of the Right-Angle Connector
Many engineers attempt to build their own null modem cables or buy generic straight-head serial cables, only to run into immediate physical problems. Expert Tip: The 1747-CP3 features a 90-degree right-angle connector on the end that plugs into the SLC processor. This is intentionally designed because the processor sits deep inside the 1746 chassis, and the control panel door is often only a few inches away. If you use a generic straight-headed serial cable, it will stick out too far, meaning you cannot close the panel door while monitoring the PLC. Leaving a high-voltage industrial panel door open while a machine runs is a massive OSHA safety violation. The right-angle head of the CP3 allows the cable to drop neatly down the wiring duct, allowing the door to close securely while you debug your program safely from outside the arc-flash zone.
Maintenance and Modern Laptop Integration
Modern engineering laptops no longer feature native 9-pin RS-232 COM ports. Therefore, the 1747-CP3 must almost always be paired with a high-quality USB-to-Serial adapter (such as the Allen Bradley 9300-USBS or a Keyspan adapter). When setting up RSLinx, you must open «Configure Drivers,» select «RS-232 DF1 devices,» choose the COM port assigned to your USB adapter by Windows, and click «Auto-Configure.» If the 1747-CP3 is correctly seated, RSLinx will automatically detect the baud rate and parity, establishing an immediate connection to the SLC processor.
Frequently Asked Questions (FAQs)
Q: Can I use the 1747-CP3 to connect an SLC to a PanelView HMI?
A: Yes! Because the 1747-CP3 is a null-modem cable, it is the exact cable required to establish point-to-point RS-232 (DF1) communication between an SLC 5/03 (Channel 0) and an older PanelView Standard HMI equipped with an RS-232 port.
Q: Will this cable work with the SLC 5/01 or 5/02?
A: No. The SLC 5/01 and 5/02 do not have 9-pin RS-232 Channel 0 ports. They only have RJ45 DH-485 ports. You would need a 1747-PIC or a 1747-UIC USB interface to connect to those older processors.
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For serial communication, this cable connects the RS-232 port of an SLC 5/03 processor directly to a PC.
