Overview
The Allen-Bradley 1747-L514 is an entry-level SLC 5/01 processor designed for the modular SLC 500 platform. This processor provides reliable control for small- to medium-scale machine automation, process monitoring, and networking applications. It features 4K instruction memory, capacitor-backed RAM, and built-in DH-485 communication for peer-to-peer network connectivity. The unit mounts in slot 0 of any 1746 modular chassis.
Key Features
- 4K Instruction Memory: Adequate program space for standard automation and process control logic
- 960 Maximum I/O Points: Supports control of up to 30 SLC 500 I/O modules across up to 3 chassis
- DH-485 Communication Port: Built-in networking for distributed I/O and multi-node messaging
- Capacitor-Backed RAM: Non-volatile data retention without battery dependency
- Modular Slot 0 Design: Single-slot installation in 1746 chassis simplifies integration
- Extended I/O Support: Compatible with 1747-M1 and 1747-M2 optional EEPROM memory modules
Technical Specifications
- Processor Type: SLC 5/01 (Catalog Number 1747-L514)
- Program Memory: 4K instructions
- User Memory Expansion: Via 1747-M1 (1K EEPROM) or 1747-M2 (4K EEPROM)
- Maximum I/O Capacity: 960 I/O points (up to 30 modules supported)
- Communication Interface: DH-485 (peer-to-peer, message command capable)
- Input Voltage: 5–24 VDC
- Backplane Current Draw: 0.090 A at 5 VDC
- Power Consumption: 1.75 W minimum
- Operating Temperature: 0–60°C
- Backup Memory: Capacitor-backed (no battery required in -L514 configuration)
- Mounting: Slot 0, 1746 modular chassis (single slot width)
- I/O Scanning: 8 ms per 1K instructions
- Supported Instruction Set: Bit logic, timers, counters, comparison, basic math, move/copy, bit shift, sequencer, jump and subroutine
Typical Applications
- Small- to medium-scale machine control and automation systems
- Basic process control with timer and counter logic
- Distributed I/O systems using DH-485 networking
- Simple packaging and material handling applications
- System upgrades from fixed-I/O SLC controllers to modular platforms
- Remote I/O and extended chassis configurations
Compatibility & Replacements
Compatible With
- 1746 modular chassis (all sizes: A, B, C, D)
- SLC 500 I/O module series (1746-IA, -OA, -IOA, -IB, -OB, -IOB, analog and specialty modules)
- RSLogix 500 programming software
- 1747-M1 and 1747-M2 optional memory modules
- 1761-NET-AIC and Advanced Interface Converter (AIC) modules for extended networking
- Allen-Bradley Data Table Access Module (DTAM) for memory table access
Replaces / Drop-In Replacement For
- Direct replacement in systems configured for 1747-L514 specifications
- Upgrade path from 1747-L511 (1K memory SLC 5/01 variant)
- Functionally equivalent to industrial surplus variants (1747-1514, 1747-L51A)
Works With
- RSLogix 500 IDE and compiler
- DH-485 communication protocol (peer-to-peer messaging)
- SLC 500 instruction set (no Structured Text or Function Blocks; ladder logic only)
- Optional accessories: 1747-M memory modules, 1761-NET-AIC networking adapter
