Allen-Bradley 1336-L6/B Logic Interface Board – Obsolete 1336 PLUS Series Spare Part

Technical Dossier

Product Details And Specifications

Allen-Bradley 1336-L6/B Logic Interface Board – Obsolete 1336 PLUS Series Spare Part

When a 1336-L6/B logic interface board fails inside a running 1336 PLUS or 1336 IMPACT variable frequency drive, the production line does not pause politely. It stops. For facilities still operating Rockwell Automation's 1336-series VFD infrastructure, that stoppage carries a cost that extends far beyond the price of a replacement board. A full drive replacement—hardware, engineering hours, rewiring, recommissioning, and retraining—routinely runs into tens of thousands of dollars per unit. Multiply that across a multi-drive installation and the capital exposure becomes a board-level decision, not a maintenance call.

The 1336-L6/B has been discontinued by Allen-Bradley. Rockwell Automation no longer manufactures or supports this board through standard distribution channels. DriveKNMS holds verified physical inventory of this part. Procurement windows for obsolete Rockwell boards close without notice. Facilities that have not secured a buffer stock of critical interface boards are operating on borrowed time.

Technical Specifications

Note: Electrical parameters specific to this board revision are not published in open documentation. DriveKNMS does not fabricate specifications. Contact our technical team for application-specific verification before installation.

Solving the Discontinued Hardware Crisis

The Allen-Bradley 1336 PLUS and 1336 IMPACT drive families were workhorses of industrial automation through the 1990s and 2000s. Thousands of units remain in active service across water treatment facilities, paper mills, mining operations, and discrete manufacturing lines worldwide. The logic interface board is the communication and control backbone of these drives—it manages the interface between the drive's control circuitry and external command signals. Without a functioning 1336-L6/B, the drive cannot receive speed references, respond to start/stop commands, or communicate with the host PLC or DCS.

Rockwell Automation's end-of-life policy for the 1336 series means that OEM replacement boards are no longer available through authorized distributors. Facilities that experience a board failure today face three options: locate a verified aftermarket unit, retrofit the drive with a newer platform, or replace the entire drive. The retrofit and replacement paths both require engineering resources, process downtime, and capital expenditure that most maintenance budgets are not structured to absorb on an emergency basis.

Securing a 1336-L6/B from DriveKNMS's existing inventory eliminates that emergency. The drive returns to service. The production schedule holds. The capital replacement project, if it is planned at all, proceeds on the facility's timeline rather than the failure's timeline.

How to Extend Automation Asset Life by 5–10 Years Through Strategic Spare Parts Management

For plant managers and reliability engineers operating legacy Rockwell Automation infrastructure, the following framework has been applied successfully across multiple industrial sectors to defer costly system replacements while maintaining production reliability:

• Criticality mapping: Identify every 1336-series drive on site. Classify each by production impact if it fails. Drives on critical process lines with no bypass capability are Tier 1 assets requiring immediate spare board coverage.
• Mean Time Between Failure (MTBF) analysis: Logic interface boards in drives operating in high-ambient-temperature or high-vibration environments degrade faster. Drives installed before 2005 with no board replacement history are statistically overdue.
• Buffer stock calculation: For a fleet of 10–30 drives of the same family, industry practice supports holding 2–3 spare logic boards. The cost of those boards is recovered in full by avoiding a single unplanned stoppage event.
• Phased modernization: Rather than replacing all 1336-series drives in a single capital project, facilities can use verified spare boards to maintain the existing fleet while systematically replacing drives during scheduled shutdowns. This approach spreads capital expenditure over 5–10 years and avoids the operational risk of large-scale simultaneous changeovers.
• Vendor-managed obsolete inventory: Establish a supply relationship with a specialist distributor—such as DriveKNMS—that actively sources and holds obsolete Rockwell boards. Spot-market availability for parts like the 1336-L6/B is unpredictable. Pre-negotiated access to verified inventory removes procurement risk from the maintenance equation.

Condition & Reliability Assurance

DriveKNMS applies a 5-step quality assurance process to all obsolete boards before shipment. This process is designed specifically for the failure modes common to PCB assemblies that have been in storage or field service for extended periods.

1. Electrolytic capacitor inspection: Capacitor aging is the primary failure mechanism in logic boards from this era. Each board is inspected for bulging, leakage, and ESR deviation. Boards with degraded capacitors are recapped with equivalent-specification components before release.
2. Firmware version verification: Where applicable, firmware revision is confirmed against the board's part number suffix to ensure compatibility with the target drive revision.
3. Pin and connector corrosion audit: All edge connectors and pin headers are inspected under magnification for oxidation, corrosion, and mechanical damage. Affected contacts are cleaned or the board is rejected from inventory.
4. Functional bench test: Boards are powered and tested against known-good reference signals where test fixtures are available for the specific part number.
5. Packaging for long-term storage: Units are shipped in anti-static packaging with desiccant. Boards intended for buffer stock are packaged to support storage periods of up to 5 years without degradation.

Key Features for System Maintenance

• Drop-in replacement: The 1336-L6/B installs directly into the existing drive chassis using the original mounting points and connectors. No mechanical modification is required.
• No reprogramming required: Drive parameters stored in the drive's memory are not affected by a logic board replacement. The drive returns to its previous operating configuration without parameter re-entry, provided the drive's parameter memory is intact.
• No engineering redesign: Unlike a drive replacement or retrofit, a board-level repair does not require changes to the control panel wiring, PLC program, or process interlocks. Commissioning time is measured in hours, not days.
• Preserves existing safety certifications: Facilities operating under process safety management (PSM) or functional safety frameworks benefit from maintaining the original drive hardware, which avoids triggering re-validation requirements that a new drive installation would impose.

FAQ

What warranty applies to the 1336-L6/B?
DriveKNMS provides a 12-month warranty on all refurbished boards and a 6-month warranty on New Old Stock units. Warranty covers functional failure under normal operating conditions and excludes damage from incorrect installation or electrical overstress.

How do I confirm the board is genuine Allen-Bradley and not a counterfeit?
All boards sourced by DriveKNMS are inspected for OEM markings, PCB layer construction, and component date codes consistent with authentic Rockwell Automation manufacturing. Documentation of inspection findings is available upon request for critical procurement decisions.

Should I order more than one unit?
For facilities with multiple 1336 PLUS or 1336 IMPACT drives, holding at least one spare 1336-L6/B per 10 drives is a defensible maintenance position. Given the unpredictable availability of this obsolete part, procurement teams are advised to secure buffer stock while verified inventory exists. DriveKNMS can discuss volume pricing for multi-unit orders.

Can this board be used in both 1336 PLUS and 1336 IMPACT drives?
The 1336-L6/B is associated with the 1336 PLUS family. Compatibility with specific 1336 IMPACT configurations should be verified against the drive's catalog number and firmware revision before installation. Contact DriveKNMS for application-specific guidance.

© 2026 DriveKNMS. All trademarks belong to their respective owners. Specifications are for reference only and subject to change without notice. Verify all parameters against official documentation before installation.