PRODUCT INFORMATION
Product Overview
Revision scope: These specifications describe 1747-L542/A (Series A). Check the corresponding technical data before specifying another hardware series.
The Allen-Bradley 1747-L542 is an SLC 500 SLC 5/04 Processor module for industrial automation racks. It features 32K words of battery-backed RAM divided into program and data areas. The unit supports up to 4,096 discrete inputs and 4,096 discrete outputs across three chassis. RSLogix 500 programming software executes ladder logic with a typical 0.9 millisecond per kiloword scan rate.
Communication options include a Data Highway Plus port and an RS-232 multi-protocol serial channel. The RS-232 port supports DF1, DH-485, ASCII, and Modbus RTU communication protocols. The module mounts into slot zero of any compatible SLC 500 chassis backplane. It draws 1 ampere at 5 volts DC and 175 milliamperes at 24 volts DC.
TECHNICAL DATA
Technical Specifications
These specifications describe 1747-L542/A (Series A). Check the corresponding technical data before specifying another hardware series.
| Parameter | Specification |
|---|
| Specification | Value |
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| Processor Type | SLC 5/04 |
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| User Memory | 32K Words (battery-backed RAM); 28K program/data + 4K data only |
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| Flash Backup Memory | Flash EPROM (via 1747-M13 memory module) |
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| Discrete I/O Capacity | Up to 4,096 Inputs / 4,096 Outputs |
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| Analog I/O Capacity | Up to 480 Points |
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| Communication Ports | Channel 0: RS-232 (DF1, DH-485, ASCII, Modbus RTU); Channel 1: Data Highway Plus (DH+) |
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| Backplane Voltage | 5V DC / 24V DC |
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| Backplane Current Draw | 1 A at 5V DC; 175 mA at 24V DC |
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| Thermal Dissipation | 4 W |
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| Program Scan Time | 0.9 ms/K (typical) |
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| I/O Scan Time | 0.225 ms (typical) |
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| Bit Execution Time (XIC) | 0.37 ms |
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| Operating Temperature | 0 to 60°C (32 to 140°F) |
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| Storage Temperature | -40 to 85°C (-40 to 185°F) |
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| Relative Humidity | 5 to 95%, non-condensing |
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| Operating Shock | 30G |
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| Vibration | 2.5G at 57–2000 Hz; 0.015 in. displacement (pk-pk) at 5–57 Hz |
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| Local I/O Chassis / Max Slots | 3 Chassis / 30 Slots |
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| Dimensions (W x H x D) | 35 x 145 x 142 mm (1.38 x 5.71 x 5.59 in.) |
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| Programming Software | RSLogix 500 |
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| Mounting | SLC 500 Chassis Backplane (Slot 0) |
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| Hazardous Location Rating | Class I, Division 2, Groups A, B, C, D |
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| Certifications | UL Listed (US & Canadian Standards), CE, C-Tick |
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TECHNICAL INFORMATION
Order Information
| Revision Part # | Also known as | Reference Price |
|---|
| 1747-L542 Ser A | 1747-L542/A, Series A | USD 429.00, indicative (Used/Refurbished) |
| 1747-L542 Ser B | 1747-L542/B, Series B | USD 398.00, indicative (Used/Refurbished) |
| 1747-L542 Ser C | 1747-L542/C, Series C | USD 459.00, indicative (Used/Refurbished) |
| 1747-L542 Ser D | 1747-L542/D, Series D | USD 1,090.00, indicative (Used/Refurbished) |
Reference prices are observed third-party market prices for the stated revision, not a final Aituos quotation.
TECHNICAL INFORMATION
Features
- Provides 32K words of battery-backed user memory for program and data storage.
- Supports 4,096 discrete inputs and 4,096 discrete outputs across local racks.
- Includes one Data Highway Plus port and one configurable RS-232 serial port.
- Offers optional non-volatile program backup using a 1747-M13 Flash EPROM module.
- Executes basic bit instructions in 0.37 milliseconds with fast typical scan times.
- Consumes 4 watts of thermal dissipation during standard backplane operation.
TECHNICAL INFORMATION
Applications
- Manages discrete and analog I/O control across multi-chassis SLC 500 modular systems.
- Provides networking on Data Highway Plus networks for plant-wide peer-to-peer data communication.
- Coordinates serial communications with peripheral devices using DF1, DH-485, ASCII, or Modbus RTU.
TECHNICAL INFORMATION
Connections / Interfaces
- Channel 0 provides an RS-232 serial interface for multiple industrial protocols.
- Channel 1 provides a Data Highway Plus interface for peer communications.
- The module connects directly to the SLC 500 chassis backplane bus.
TECHNICAL INFORMATION
Installation Guidelines
- Insert the processor into slot 0 of the first SLC 500 chassis.
- Ensure power to the chassis power supply is disconnected before module installation.
- Maintain ambient operating temperatures between 0 and 60 degrees Celsius.
TECHNICAL INFORMATION
Configuration Guidelines
- Configure processor settings and logic routines using Rockwell Software RSLogix 500.
- Set Channel 0 parameters to DF1, DH-485, ASCII, or Modbus RTU.
- Store user programs into the 1747-M13 Flash module for non-volatile backup.
TECHNICAL INFORMATION
Compatibility
- Installs in slot 0 of modular SLC 500 chassis systems.
- Compatible with SLC 500 discrete, analog, and specialty I/O modules.
- Supports memory expansion and backup with the 1747-M13 Flash EPROM module.
TECHNICAL INFORMATION
Compliance and Certifications
- UL Listed under United States and Canadian safety standards.
- Class I, Division 2, Groups A, B, C, D rated for hazardous locations.
- Carries CE and C-Tick compliance marks.
COMPATIBILITY
Compatibility & Replacement
COMPATIBLE MODELSInstalls in slot 0 of modular SLC 500 chassis systems. Compatible with SLC 500 discrete, analog, and specialty I/O modules. Supports memory expansion and backup with the 1747-M13 Flash EPROM module.
Verify compatibility against the exact Part Number, revision and manufacturer documentation before ordering.
PART VERIFICATION
Before You Order
Industrial automation parts can share similar model names, suffixes and revisions. Confirm the complete manufacturer Part Number before purchase.
01Check Part NumberMatch the complete ordering code on the existing unit.
02Confirm RevisionCheck suffix, hardware or firmware when applicable.
03Send a Label PhotoWe can review a clear label photo when identification is uncertain.
ORDERING PROCESS
From RFQ to Dispatch
1Submit Part Number2Verify Product Identity3Confirm Stock & Condition4Issue Quotation5Dispatch & Tracking
PRODUCT FAQ
Frequently Asked Questions
What memory configuration is available in the 1747-L542 processor?
The unit includes 32K words of battery-backed RAM. It divides into 28K program words and 4K data words.
Which communication ports are integrated into the 1747-L542?
The processor includes an RS-232 port on Channel 0 and a Data Highway Plus port on Channel 1.
Where should the 1747-L542 module be mounted?
It must be installed in slot zero of the primary SLC 500 chassis.
What is the market reference price for the 1747-L542?
Verified market observations show an indicative reference price of approximately USD 429.00 for used or refurbished units. Figures are indicative market reference pricing only and are not a final quotation.
