Allen-Bradley 1756-CP3 Logix Family RS232 Programmer Cable

Configured for serial programming and controller-to-DTE communication in ControlLogix and Logix family systems, the Allen-Bradley 1756-CP3 (1756-CP3 Logix Family RS232 Programmer Cable) provides direct physical electrical signal routing between Logix controllers and external programming or terminal devices over a 9-pin to 9-pin RS-232 interface across a 3 m (10 feet) link segment. The cable operates as a passive interconnect within the Logix communication stack, supporting redundant configuration environments and ControlNet-linked controller architectures.

Suffix Breakdown & Model Matrix

The 1756-CP3 is a single fixed configuration part number with no documented suffix segmentation or functional variant matrix. It is supplied as a standardized Logix Family RS232 programmer cable assembly.

Hardware Specifications

Allen-Bradley ControlLogix Serial Communication Architecture

The 1756-CP3 is integrated within the ControlLogix communication ecosystem where serial programming access is mapped through RS-232 DTE linkage paths. Within Allen-Bradley Logix platforms, backplane-to-communication module synchronization supports deterministic execution cycles over EtherNet/IP or ControlNet, while the 1756-CP3 provides a physical-layer terminal access route for configuration, diagnostics, and controller-level programming operations.

Firmware-level communication compatibility is maintained through Logix family controller stacks, enabling consistent configuration access behavior across redundant controller deployments and mixed communication topologies.

Frequently Asked Questions (FAQ)

Q: Does the 1756-CP3 support hot-swap during active controller communication sessions?
A: No hot-swap function is defined for RS-232 passive cable assemblies. Connection should be made only when controller serial port is in idle state to avoid frame corruption.

Q: Does the cable affect backplane current or chassis load in ControlLogix systems?
A: No direct backplane load is applied. However, system-level serial port interfacing may reflect minimal signaling current as specified by 5.1 VDC and 24 VDC reference inputs.

Q: Can the 1756-CP3 be used with EtherNet/IP-only controllers?
A: It is physically compatible only with RS-232 serial ports. EtherNet/IP communication operates independently and does not use this cable path.

Field Installation Guidelines

Ensure RS-232 connector alignment is verified before insertion into Logix controller serial ports and DTE terminal devices. Maintain cable routing separation from high-frequency power conductors and inverter output lines to minimize induced noise on serial signaling pairs.

Shield continuity should be maintained across connector shells where applicable, with grounding performed at a single-point control cabinet earth reference. Avoid tight bend radius below standard RS-232 cable mechanical tolerance to prevent conductor fatigue over repeated maintenance cycles.

Do not install under energized motion or high-vibration conditions without mechanical strain relief at both connector ends.