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Allen-Bradley 1756-L71S ControlLogix – Repair Service Available

The Allen-Bradley 1756-L71S is a GuardLogix 5570 safety controller, 2 MB GuardLogix 5570 safety controller. NJT Automation offers mail-in repair for the 1756-L71S with a 1-year warranty; replacement pricing is available on request.

Mail-in repair available now. Returned with a 1-year warranty. Replacement pricing on request.

Allen-Bradley 1756-L71S GuardLogix 5570 safety controller, 2 MB – front view
Request Replacement QuoteRequest Repair QuoteEstimated $1,440.00
Price
On Request
Previously sold for $1,999.99 USDAvailability and condition determine final quote.
DescriptionGuardLogix 5570 safety controller, 2 MB.
ShippingUPS Ground included | Next-Day Air and Worldwide Shipping available at checkout
Warranty1-year full-function warranty provided by NJT Automation.
Warranty details

The original Allen-Bradley warranty does not apply to pre-owned units. Full warranty coverage is provided directly by NJT Automation. If you have any issues we can usually swap your unit next-day air (based on inventory)-no waiting weeks for a repair.

Included: 1 Year
+1 Year: +15% of product price ($300.00)
+2 Years: +25% of product price ($500.00)
View Full Warranty Policy
Returns90-day free returns on all purchases.View return policy
Exchange

Send us your defective 1756-L71S after your purchase for a 10% core credit. We also purchase old or damaged parts outright.

Availability
Available Level 1

This part is available through our Level 1 supplier network. Request a quote to confirm quantity, price, and next-day shipping options.

Inventory Level 1 RFQ

Level 1 parts come from vetted US suppliers we have worked with for years. Each unit is checked before it ships, so counterfeits, repackaged items sold as new, and worn-out equipment do not reach you. Every part carries the same NJT warranty and return policy as our own stock.

Request QuoteLearn more about Inventory Levels
Repairs

1756-L71S Mail-In Repair Service

Estimated: $1,440.00

How the Process Works:

  1. Submit Your RFQ: Complete the request-for-quote (RFQ) form with your exact requirements.
  2. Receive a Quote: We respond ASAP - within 1 hour during business hours.
  3. Approve and Pay: Agree to the quoted price, and we will issue an invoice payable via credit card or your preferred method.
  4. Direct Shipping: Our normal shipping time is 3-5 business days, during which we thoroughly inspect and certify items to meet our high standards. If you request next-day air delivery, the item will be sent directly to you and arrive the following business day. Please note: These items are NOT available for local pickup at NJT Automation's location.

What We Offer

We source genuine parts from trusted U.S. channels and stand behind what we sell.
  • Our network has millions of parts ready to be delivered now.
  • Complete Transparency: Clear information on item availability.
  • Well-vetted components from trusted suppliers sourced from the USA.
  • Technical Support: Assistance, troubleshooting and hardware repairs.
  • Minimal Markup: The best sourcing service at a minimal cost.
  • Quick Delivery: Fast access to the parts you need to get your machines back up and running.
  • Dropship available • No branding on packaging

Part Number Decoder

GuardLogix 5570 safety controller
1756L71S

2 MB GuardLogix 5570 safety controller.

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).
1
Memory size2 MB of standard user memory plus 1 MB of safety memory.
S
SafetyGuardLogix safety controller (SIL 2 / PLd; SIL 3 / PLe with a safety partner), adds 1 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.

Similar Part Numbers

  • 1756-L72S Memory size: 4 MB of standard user memory plus 2 MB of safety memory

Allen Bradley Information

Technical Description
Allen Bradley ControlLogix Safety Controller 1756-L71S features a 2MB user memory and supports SIL 3/PLe safety applications
Lifecycle: Active — verify current status with the manufacturer

Alternate Part Numbers

1756L71s
CategoryControlLogix
Part Number1756-L71S
ManufacturerAllen-Bradley

Previously sold 1756-L71S

1 sold

NJT Automation has supplied and shipped one 1756-L71S GuardLogix 5570 safety controller. Request a quote and we will source another from our supplier network.

Allen-Bradley 1756-L71S Unused surplus (new old stock) - previously sold by NJT AutomationSold

2022 Allen Bradley 1756-L71S /B GuardLogix Processor Module - New Sealed Surplus

$1,999.99 USD

Unused surplus (new old stock)

Request Quote

Can the 1756-L71S be repaired?

Yes. NJT Automation offers mail-in repair for the 1756-L71S, including diagnostic evaluation, component-level repair, and functional testing.

NJT Managed Repair

One vendor. One warranty. NJT manages the entire process.

  • 1-year full-function NJT warranty, with 2- and 3-year options available
  • Rush service available for production-critical repairs
  • No evaluation or diagnostic charges
  • No repair, no charge
  • Pre-paid UPS shipping label provided for sending your unit in
  • $650 minimum repair charge, shipping included both ways
Get an NJT Repair Quote

Looking for another option? For lower-cost repairs or if you prefer to work directly with an independent repair specialist, compare bids through RepairMode. RepairMode providers operate independently and set their own pricing and warranty terms.

Find a PLC repair specialiston RepairMode.com ↗

Common 1756-L71S failures

Failure patterns we regularly see on GuardLogix 5570 safety controller hardware like the 1756-L71S:

  • Program lost on power cycle: energy storage module (1756-ESMCAP / ESMNSE) failing to hold the controller through a save
  • Solid red OK LED (nonrecoverable major fault) that returns after clearing
  • 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

Repair or replace?

ReplaceReplace the 1756-L71S if it will not boot, shows a solid red fault light, or has lost its program. Another GuardLogix 5570 safety controller takes the same program: download it, match the firmware, and the line is running again. Stick with the exact 1756-L71S. The suffix sets the 2 MB memory, so a near match is a different unit. A replacement 1756-L71S is sourced on request, so compare its lead time with a repair before deciding.
RepairRepair the 1756-L71S when the fault is in the power section, a port or the status display rather than the processor core, or when the controller carries a firmware revision or validated project you cannot easily re-flash onto a different unit. Most 1756-L71S units reach our bench with one of two symptoms: “Program lost on power cycle” or “Solid red OK LED (nonrecoverable major fault)”. Already swapped it out? Repairing the failed 1756-L71S turns it into a tested spare on the shelf for the next failure. The 1756-L71S repair is estimated $1,440.00, function-tested before return and covered by a 1-year warranty.

Why Choose Our Repair Service?

  • ■ Rush turnaround available, with 24-hour emergency service on some models
  • ■ 1-year full-function warranty, with 2- and 3-year extended options
  • ■ No evaluation or diagnostic charges
  • ■ Free UPS shipping label available
  • ■ "Unrepairable" is not an option
  • ■ Thousands of successful Allen-Bradley restorations

Request a Repair Quote

Ready to repair your 1756-L71S? Request a repair quote below. For immediate assistance, text photos of your faulty unit and a description of the symptoms to (414) 331-5954.

Start Your Repair Today

All product photos were taken by NJT Automation. Test videos originated from either NJT Automation internally or from repair technicians within our network.

Still have questions?

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

The Allen-Bradley 1756-L71S is a GuardLogix 5570 safety controller: 2 MB GuardLogix 5570 safety controller.
The 1756-L71S is available in Unused surplus / Refurbished / Used condition. We can quote this part in unused surplus, refurbished, or used condition depending on availability and your preference. Specify your requirement in the RFQ.
This 1756-L71S is sourced on request, so sourcing and quote timelines apply. Request a quote and we'll confirm availability and lead time. Many parts can be sourced within a few business days through our Level 1 supplier network.
Yes. UPS Next Day Air is available at checkout for the 1756-L71S. Place your order before 5:00 PM Central on a business day and your in-stock item ships the same day for next-business-day delivery.
Yes. Once your 1756-L71S has been sourced and is ready, free local pickup is available at NJT Automation, 2122 N Prospect Ave, Milwaukee, WI, during business hours.
2 MB of standard user memory plus 1 MB of safety memory.
1756-L71S breaks down as: 1756 = ControlLogix; L = Logix controller (CPU module); 7 = ControlLogix 5570; 1 = 2 MB of standard user memory plus 1 MB of safety memory; S = GuardLogix safety controller (SIL 2 / PLd; SIL 3 / PLe with a safety partner).
NJT Automation

NJTAutomation

Industrial Electronics

Supply & Repair, Milwaukee WI

(414) 331-5954EmailRequest a quote

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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.

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