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Allen-Bradley 1756-L72S ControlLogix Processor 4 MB

In stock: 1 unit in Milwaukee, WI. Physically stocked and ready to ship or available for local pickup. Includes a 1-year full-function warranty.

4 MB GuardLogix 5570 safety controller

Price

$749.99USD

Used units available

Request Repair QuoteEstimated $1,440.00
Part Number1756-L72S
DescriptionGuardLogix 5570 safety controller, 4 MB. In stock in used condition, Series B.
Shipping
Ships same or next business day UPS Ground included | Next-Day Air and Worldwide Shipping available at checkout
Pickup
Free local pickup at 2122 N Prospect Ave. Call ahead at (414) 331-5954.
Warranty
1-year full-function warranty provided by NJT Automation.
Warranty details
Included
1 year, full-function
2 years
+15% of product price ($112.50)
3 years
+25% of product price ($187.50)
View full warranty policy
Returns
90-day free returns. View return policy
Exchange

Send us your defective 1756-L72S after your purchase for a 10% core credit ($75). We also purchase old or damaged parts outright.

Replacement Options for 1756-L72S

Pick a condition and series below. UPS Ground shipping included.

ALLEN BRADLEY 1756-L72S SER B Logix 5572S Automation Controller 4M/2M

$749.99 USDIn-stock match

Condition: Used

Series B

1 in stockView details
Variants
Part NumberConditionSeriesQtyPrice
1756-L72S /B$749.99
Used · Series B · 1 in stock
1756-L72S /BUsedSeries B1$749.99 USD

1756-L72S

Refurbished — pick series, then request a quote

Request Quote
1756-L72SRefurbished—Request Quote
Availability
1 unit in stock
Repairs

1756-L72S Mail-In Repair Service

Estimated: $1,440.00

Part Number Decoder

GuardLogix 5570 safety controller
1756L72S
1756
BulletinControlLogix: Rockwell Automation's chassis-based control platform (controllers, I/O, communication modules, power supplies and chassis).
L
Module typeLogix controller (CPU module).
7
GenerationControlLogix 5570: Logix5570 series (USB programming port, SD card, energy storage module).
2
Memory size4 MB of standard user memory plus 2 MB of safety memory.
S
SafetyGuardLogix safety controller (SIL 3 / PLe when paired with a 1756-LSP safety partner in the adjacent slot; it is not rated for safety on its own), adds 2 MB of safety memory alongside the standard memory.
Decoded from the Rockwell Automation catalog-number structure. Series and firmware revision are printed on the product label, not encoded here.

Series & Revisions

Series B in stock; other series on request.

All series use the 1756-ESMCAP energy-storage module and a 1784-SD1 / SD2 card; no battery.

Series notes: Studio 5000 keys on catalog number and firmware revision, not series.

Intended Use

Intended for plant-wide discrete, process, and motion control applications. ControlLogix controllers run high I/O-count machines, batch and continuous process lines, and coordinated multi-axis motion from a single chassis, with redundancy and plant-network connectivity when the application calls for it. Typical homes are automotive and tire plants, food and beverage lines, water and wastewater, oil and gas skids, and large packaging systems. Safety-rated for use in GuardLogix safety chains up to SIL 3 / PLe.

Physical Data

Weight and DimensionsWeight0.87 lb (0.39 kg)H × W × D5.7 × 1.4 × 5.7 in. (145 × 35 × 145 mm)
Weight0.39 kg (0.87 lb)
Typical unit weight
Dimensions (H × W × D)145 × 35 × 145 mm (5.7 × 1.4 × 5.7 in.)
Single-slot controller module
Shipping Weight0.92 kg (2.03 lb)
Estimated: unit weight plus box and packing material; bills as 3 lb
Shipping Box (L × W × H)12 × 12 × 8 in. (305 × 305 × 203 mm)
Smallest standard box fitting the product with 3 in. cushioning per side
Product weight and dimensions are typical manufacturer-published values and may differ by series or option. Shipping box and weight are estimates for freight planning; the packed unit may ship in a different box.
CategoryControlLogix
Part Number1756-L72S
ManufacturerAllen-Bradley

Can the 1756-L72S be repaired?

Yes. NJT Automation repairs the 1756-L72S by mail-in: diagnostic evaluation, component-level repair and a functional test, backed by a 1-year full-function warranty.

NJT managed repair. No evaluation fee; no repair, no charge. Prepaid UPS label both ways, $650 minimum, rush available. 1-year full-function warranty included, 2- and 3-year options.

Get a repair quoteor text photos and symptoms to (414) 331-5954

Compare quotes from independent repair technicians. Post your repair on RepairMode to receive competitive bids from experienced technicians. Each technician sets their own pricing and warranty.

Find a PLC repair specialiston RepairMode.com ↗

Common failures

Failure patterns we regularly see on GuardLogix 5570 safety controller hardware like the 1756-L72S:

  • SD card corruption preventing the stored project from loading at power-up
  • Front USB port failure: Studio 5000 will not connect over USB
  • Scrolling status display blank or unreadable
  • Backplane communication faults from bent chassis pins after repeated module swaps
  • Program lost on power cycle: energy storage module (1756-ESMCAP / ESMNSE) failing to hold the controller through a save

Photos by NJT Automation; test videos from NJT or network repair technicians.

Still have questions?

Find answers to shipping, warranties, repairs, and more.

The Allen-Bradley 1756-L72S is a GuardLogix 5570 safety controller: 4 MB GuardLogix 5570 safety controller.
NJT Automation currently has 1 unit of the 1756-L72S in stock in used condition (Series B). Each listing states its own condition and series. Used means a unit removed from service and sold without refurbishment. Cosmetic condition, any functional testing performed, and the warranty term are stated on each unit’s own listing. From the listing: USED Lightly Used (nearly new): This NJT certified item is in excellent condition and comes with a 90-day warranty. You can expect this item to perform as well as a new item.
1 unit of the 1756-L72S GuardLogix 5570 safety controller are on the shelf in Milwaukee, WI, priced from $749.99. Orders before 5:00 PM Central on a business day ship the same day; next-day air is available at checkout.
4 MB of standard user memory plus 2 MB of safety memory.
Disclaimer

Trademarks & Compatibility

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Independent Supplier

NJT Automation is an independent supplier of surplus, refurbished, and pre-owned industrial automation equipment. Unless expressly stated otherwise, NJT Automation is not an authorized distributor, dealer, representative, or affiliate of the original equipment manufacturer (OEM) for any products offered on this website.

Product Condition & Warranty

Products sold by NJT Automation may be surplus inventory, discontinued models, older series, or units with earlier manufacturing date codes than those currently available from the OEM or its authorized distribution network. As NJT Automation is not an authorized distributor, manufacturer warranties, support programs, and other OEM services may not apply. Any warranty provided is solely that of NJT Automation, where applicable.

Firmware & Software Licensing

Certain programmable logic controllers (PLCs), drives, HMIs, and other electronic products may require firmware to operate. While some products may include firmware, NJT Automation makes no representations or warranties regarding whether firmware is installed, the firmware version or revision level, its compatibility with your application, or its licensing status.

NJT Automation does not provide, obtain, transfer, or license firmware on behalf of customers. We make no representation regarding your ability or legal right to obtain, download, install, or use firmware from the OEM, its authorized distributors, or any other source. It is the customer's sole responsibility to ensure compliance with all applicable End User License Agreements (EULAs), software licenses, intellectual property rights, and other terms governing the acquisition, installation, and use of firmware.