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Allen-Bradley 1747-L40C SLC 500 Processor

The Allen-Bradley 1747-L40C is an SLC 500 fixed controller with 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
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Price
On Request
Availability and condition determine final quote.
DescriptionSLC 500 fixed I/O controller.
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
+2 Years: +25% of product price
View Full Warranty Policy
Returns90-day free returns on all purchases.View return policy
Exchange

We will purchase your old or damaged parts.

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 inventory is available within our supplier network. We confirm prices, quantities, and next-day shipping options with the quote. We've built relationships with trusted suppliers across the United States and carefully screen out vendors that sell counterfeits, low-quality used equipment, or repackaged items marketed as new. We specialize in hard-to-find Allen Bradley components, offering top-quality replacement parts at a reasonable price, backed by reliable service and warranty.

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 with 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.

Allen Bradley Information

Technical Description
Allen Bradley SLC 500 Programmable Logic Controller (PLC) 1747-L40C
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
  • 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

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 1747-L40C? 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

Still have questions?

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

The Allen-Bradley 1747-L40C is an SLC 500 fixed controller with 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. 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).
1747-L40C breaks down as: 1747 = SLC 500; L = Fixed-hardware controller; 40 = 24 inputs / 16 outputs (40 I/O); C = 24V DC sinking inputs, relay outputs, 120/240V AC power.
NJT Automation

NJTAutomation

Industrial Electronics

Supply & Repair, Milwaukee WI

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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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