The Allen-Bradley 1747-L551, also cataloged as the 1747-L551 SLC 5/05 Controller, operates as a dedicated hardware component for executing user application logic and Ethernet-based data communication within SLC 500 control platforms.

Model Identification

The 1747-L551 is a SLC 5/05 processor module with 16 KB user memory capacity, RS-232 and Ethernet communication interfaces, and support for RSLogix 500 programming software. The controller executes ladder logic programs with a listed program scan time of 0.9 ms/K.

Hardware Specifications

Industrial Control Network Compatibility

The 1747-L551 processor integrates SLC 500 backplane communication with Ethernet networking capability for controller-to-controller data exchange and supervisory communication. The processor architecture supports deterministic PLC execution by coordinating I/O updates, ladder program scanning, and communication servicing.

The SLC 500 platform uses fixed processor memory mapping and modular I/O expansion. The 1747-L551 firmware environment supports application execution through RSLogix 500 programming tools and maintains user data through battery-backed RAM and Flash EEPROM storage.

Communication and Firmware Characteristics

The controller provides Ethernet and RS-232 communication channels for programming, monitoring, and system integration tasks. Firmware flash compatibility allows application retention and controller maintenance without replacing the processor hardware.

The SLC 500 backplane communication structure manages local I/O data exchange between processor modules and installed chassis modules. Network configuration should follow Allen-Bradley addressing and communication parameter requirements.

Ordering Information

• 1 x Allen-Bradley 1747-L551 SLC 5/05 16K Controller module
• 1 x Installed processor housing assembly
• 1 x Factory-installed firmware memory hardware
• Compatible SLC 500 chassis installation required separately

Field Installation Guidelines

Module Mounting

• Install the processor into the designated SLC 500 chassis slot.
• Confirm chassis power is removed before module insertion or removal.
• Verify module seating and locking tabs before energizing the system.

Communication Wiring

• Use proper Ethernet cabling and RS-232 wiring according to network design requirements.
• Separate communication cables from high-voltage power wiring to reduce electrical interference.
• Confirm communication addressing before connecting the controller to an active network.

Maintenance Considerations

• Verify battery-backed memory status during scheduled maintenance.
• Maintain firmware compatibility between processor and application software.
• Ground shielding according to industrial control cabinet wiring practices.

Frequently Asked Questions

• What memory capacity does the 1747-L551 provide?

The controller provides 16 KB user memory with battery-backed RAM for SLC 500 application storage and processor operation.

• Which programming software is used with the 1747-L551?

The 1747-L551 is programmed using RSLogix 500 software for ladder logic development and controller configuration.

• Does the 1747-L551 support Ethernet communication?

Yes. The processor includes Ethernet communication capability for programming, monitoring, and network data exchange.

• What communication ports are available on this controller?

The module provides Ethernet and RS-232 communication interfaces for system configuration and data communication.

• What is the operating temperature range?

The specified operating temperature range is 0 to 60 deg C for normal controller operation.

• What is the processor scan performance?

The controller provides a listed program scan time of 0.9 ms/K instruction execution.

• What type of memory storage is used?

The controller uses battery-backed RAM and Flash EEPROM memory for application storage and retention.

• Can the 1747-L551 replace other SLC 500 processors?

Replacement compatibility depends on chassis configuration, program requirements, firmware revision, and communication architecture.