1-919-535-3180 | 1-800-360-6802

GE / IP FANUC Series 90/30 In Stock

A Global Supplier of Industrial Electronics



Mon-Fri 8AM-5PM EST



Rated 4.4/5 Based on 35 ratings.

Rate your purchase of the 1747-L551

Allen Bradley | SLC-500 | 1747-L551 | Image

Allen Bradley | SLC-500 | 1747-L551 | Image

Includes a PDF Electric and Supply warranty.

(Never Used)


2 In Stock

3 Yr PDF Supply warranty

What is Surplus?



1 In Stock

2 Yr PDF Supply Warranty

What is Refurbished?

Repair Service


5-10 Days

2 Yr PDF Supply warranty


Other Available Revisions for the 1747-L551 1747-L551/A1747-L551/B1747-L551/C1747-L551/D

Common misspellings:
  • l747-L551
  • 17A7-L551
  • 1747-1551
  • 1747-L55l
  • 1747L551

The Allen Bradley 1747-L551 processor Hardware SLC is one member of the Allen Bradley SLC 500 product line. The 1747-L551 has a program memory size of 16KB and is considered a high-performance module due to its modern port that shortens execution time and makes communication much faster than before. Up to 4,096 input and output points are controlled by this SLC processor. One of this unit’s most convenient features is its runtime editing programming feature.


The 1747-L551 processor contains DeviceNet pass-through, remote I/O, and channel-to-channel features in addition to its built-in calendar and real time clock. It comes along with a DH-485 channel and may also come with an RS-232 channel, which supports DF1 full duplex for the purpose of point-to-point communication. The RS-232 can also serve as support to the DF1 radio modem and DF1 half-duplex master.


To ensure support certain functions such as high-speed communication, SNMP, extended messaging capabilities, and BOOTP, the 1747-L551 has a built in 10/100 Base-T Ethernet port. It contains programming capabilities for various additional instructions and advanced math instructions. On the basis of UL 508, CSA C22.2 No. 142 standards, the 1747-L551 can withstand about 150 Volts of Active Current (AC). It operates at a vibration of 2.5 g at 5 to 2000 Hertz and at 5 g its non-operating vibration ranges from 5 to 2000 Hertz. The 1747-L551 processor isolation between the communication circuits approximates to 1500 Volts Active Current.


This unit has a user memory capable of storing up to about 16,000 words; in addition, it takes a minimal 0.9 milliseconds to scan the entire unit’s programs. It has a backup Flash memory and thirty (30) chassis module slots. Do not store this module in temperatures outside of the safe range of -40 to 185 degrees Fahrenheit or operate it in a temperature zone outside of 32 to 140 degrees Fahrenheit.

Technical Specifications for 1747-L551

ManufacturerAllen-Bradley / Rockwell Automation
SeriesSLC 500
Part number1747-L551
Product typeModular processor
Memory16K words
I/O capacity4096 discrete I/O
Maximum number of chassis3
Maximum number of I/O slots30
Input voltage1 Amp at 5 Volts DC, 0 milliamps at 24 Volts DC
Memory backupFlash EPROM
Operating temperature0 to 60 degrees Celsius
Relative humidity5 to 95%
Operating shock30 g

About 1747-L551

The Allen-Bradley 1747-L551 processor is a modular processor which belongs to SLC 5/05 series from the SLC 500 product line. The hardware features of the SLC 5/05 processor include 16K to 64K words of memory, online programming, a built-in 10/100 Mbps Ethernet interface, a built-in RS-232 interface, a channel to channel passthru feature, a built-in real time clock, indirect addressing, and battery-backed RAM. The 1747-L551 processor also includes a memory module, a keyswitch, an Ethernet interface, an RS-23 interface, and a battery. The processor supports a total of 4096 discrete I/O, 3 chassis, and 30 I/O slots. The number of remote I/O is limited by the chassis power and processor memory to 4096 outputs and 4096 inputs. The oower consumption of the processor is 4 Watts.

The “RUN” LED indicator on the 1747-L551 processor is on when the processor is in the run mode, it flashes when the processor is transferring a program from the RAM to the memory module, and it is off when the processor is in a different operating mode. The keyswitch on the 1747-L551 processor can be used to select 1 of 3 operating modes including the run, program, and remote mode. In the run mode, the processor executes the ladder program, monitors the inputs, and activates the outputs. The program mode can only be used for online program editing. In the program mode, the ladder program is not executed and the outputs are deactivated. The remote mode can be used for program editing. The temperature ranges for operation and storage are 32 to 140 degrees Fahrenheit and -40 to 185 degrees Fahrenheit, respectively.
The Allen-Bradley 1747-L551 processor is an SLC 5/05 series processor. The amount of user memory available on the processor is 16K words.

F.A.Q for 1747-L551

All online orders placed before 4:30 PM EST “SHIPS SAME DAY FREE!" World’s largest warehouse of Factory Sealed GE 90-30 PLC, GENIUS I/O and RX7i PACSystem.highlight_off

PDF Electric & Supply Inc. sells new, new surplus and refurbished products which are sourced through independent channels. All warranties and support, if applicable, are with PDF Electric & Supply Inc. and not the manufacturer. PDF Electric & Supply Inc. is not an authorized distributor or representative for the listed manufacturers and makes no representations as to any quality control performed by any listed manufacturer on the products. The products listed on this website may vary as to their country of origin; the accessories, and other items included with the product; and the language used on the packaging, the parts, and any related instructions or printed material related to the products. This website is not sanctioned or approved by any manufacturer or tradename listed. Designated trademarks, brand names and brands appearing herein are the property of their respective owners.