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Allen-Bradley 1747-L40C SLC 500 Processor

Allen-Bradley 1747-L40C SLC 500 Fixed Controller, 24 inputs / 16 outputs (40 I/O), 24V DC sinking inputs, relay outputs, 120/240V AC power. NJT Automation sources the 1747-L40C on request; send the part number for a replacement or repair quote.

Quote required. Request a quote below for pricing and delivery.

Allen-Bradley 1747-L40C SLC 500 Fixed I/O Controller - replacement part available from NJT Automation
Request Replacement QuoteRequest Repair Quote
Part Number1747-L40C
Price
On Request
Availability and condition determine final quote.
DescriptionSLC 500 Fixed I/O Controller.
Shipping
UPS Ground included | Next-Day Air and Worldwide Shipping available at checkout
Warranty
1-year full-function warranty provided by NJT Automation.
Warranty details
Included
1 year, full-function
2 years
+15% of product price
3 years
+25% of product price
View full warranty policy
Returns
90-day free returns. View return policy
Exchange

Send us your defective 1747-L40C 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

1747-L40C Mail-In Repair Service

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

SLC 500 Fixed I/O Controller
1747L40C

SLC 500 Fixed Controller, 24 inputs / 16 outputs (40 I/O), 24V DC sinking inputs, relay outputs, 120/240V AC power; accepts one 2-slot expansion chassis.

1747
BulletinSLC 500: Allen-Bradley's small/medium modular PLC family. Bulletin 1747 covers processors, communication modules and accessories; chassis, power supplies and I/O modules are bulletin 1746.
L
Product typeFixed-hardware controller: processor, power supply and I/O in one unit.
40
I/O count24 inputs / 16 outputs (40 I/O).
C
I/O configuration24V DC sinking inputs, relay outputs, 120/240V AC power.
Decoded from the Rockwell Automation catalog-number structure. Series and firmware revision are printed on the product label, not encoded here.

Datasheet

Datasheet available for download
Generated from product specifications; not an official Allen-Bradley datasheet. For an official datasheet, contact Allen-Bradley or an authorized distributor.

Allen Bradley Information

Lifecycle: Discontinued. Verify current status with the manufacturer.

Alternate Part Numbers

1747L40C, 1747-L4OC
CategorySLC 500
Part Number1747-L40C
ManufacturerAllen-Bradley

Can the 1747-L40C be repaired?

Yes. NJT Automation offers mail-in repair for the 1747-L40C, 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
  • "Unrepairable" is not an option
  • 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 1747-L40C failures

Failure patterns we regularly see on SLC 500 Fixed I/O Controller hardware like the 1747-L40C:

  • Welded or burned output relay contacts on high-cycle machines
  • Power supply section failure leaving a dead unit
  • Program lost after a power event (EEPROM / capacitor backup failure)
  • Input circuit damage from field shorts
  • DH-485 port damaged or intermittent

Repair or replace?

ReplaceReplacement SLC 500 Fixed I/O Controller units are usually surplus or refurbished. Replace the 1747-L40C if it is dead or faulting and you have a current program backup. Check that the series and firmware match your project first. We source the 1747-L40C on request, so weigh that lead time against a repair turnaround.
RepairRepair keeps the exact 1747-L40C your program and licensing were validated on and can preserve the memory contents when no backup exists. It is usually the better call for battery-holder corrosion, a damaged comm port or a failed power section when matching stock is scarce. Most 1747-L40C units reach our bench with one of two symptoms: “Power supply section failure leaving a dead unit” or “Program lost after a power event”. Already swapped it out? Repairing the failed 1747-L40C turns it into a tested spare, and on an older platform that spare can be hard to buy later. Every 1747-L40C repair is fully function-tested and covered by a 1-year warranty.

Request a Repair Quote

Text photos of the faulty unit and 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 1747-L40C is an SLC 500 Fixed Controller, 24 inputs / 16 outputs (40 I/O), 24V DC sinking inputs, relay outputs, 120/240V AC power; accepts one 2-slot expansion chassis.
The 1747-L40C 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 1747-L40C 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 1747-L40C SLC 500 Fixed I/O Controller. 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 1747-L40C has been sourced and is ready, free local pickup is available at NJT Automation, 2122 N Prospect Ave, Milwaukee, WI, during business hours.
24 inputs / 16 outputs (40 I/O).
NJT Automation

NJTAutomation

Industrial Electronics

Supply & Repair, Milwaukee WI

(414) 331-5954EmailRequest a quote

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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.

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