Allen-Bradley 1336-L4 Option Board: Enables High-Performance Vector Control

Technical Specifications

Main Features and Advantages

The primary feature and advantage of the Allen-Bradley 1336-L4​ board is its ability to unlock high-performance closed-loop vector control in a 1336 PLUS drive. This control mode provides dramatically improved speed regulation accuracy, often down to 0.01% of base speed, compared to the 0.5-3% typical of open-loop V/Hz control. It enables the drive to produce 100% rated motor torque at zero speed, which is essential for holding loads or starting under full load. The 1336-L4​ provides the critical feedback that allows the drive’s control algorithm to decouple motor flux and torque, resulting in faster dynamic response to load changes and speed reference commands. This capability is vital for applications requiring quick acceleration/deceleration or precise following of a master reference.The board is designed for reliable signal acquisition in the electrically noisy environment of a drive cabinet. It typically includes differential line receiver inputs (RS-422 type) for the encoder signals, which provide excellent common-mode noise rejection, ensuring signal integrity over longer cable runs. The Allen-Bradley 1336-L4​ also supplies the +5VDC power required by most incremental encoders, simplifying system wiring. Its integration is seamless; once installed and configured via the drive’s keypad or software, the drive automatically utilizes the encoder feedback for control. This plug-and-play functionality, combined with the robust performance gains, makes the 1336-L4​ a cost-effective upgrade path. It allows users to leverage the robustness and power range of the 1336 PLUS drive platform for applications that would otherwise require a more expensive dedicated servo system, maximizing the value and capability of the existing drive investment.

Application Field

The Allen-Bradley 1336-L4​ encoder board is deployed in any industrial application where a 1336 PLUS AC drive is used and requires precision motion control beyond the capabilities of standard V/Hz operation. A primary application is in web handling and converting machinery, such as in printing presses, coaters, and laminators. Here, the 1336-L4​ enables precise dancer or load cell-based tension control by providing exact speed feedback for regulating the draw between sections, preventing web breakage or wrinkling. In center-wind and unwind applications for paper, film, or textiles, the board’s feedback is crucial for maintaining constant tension as the roll diameter changes, requiring accurate torque and speed control.In material handling, the 1336-L4​ is used on high-performance conveyor systems that require synchronous transfer or precise positioning, such as in assembly or packaging lines. It is also essential for controlling high-inertia loads like centrifuges, large fans, or rotary kilns, where the drive must manage inertia mismatch and provide controlled acceleration/ deceleration curves. Machine tool applications, such as lathe spindles or grinders, benefit from the tight speed regulation and full-torque-at-zero-speed capability enabled by the board. Furthermore, in test stands and simulators, the Allen-Bradley 1336-L4​ allows the drive to act as a dynamic load, precisely controlling torque and speed for product testing. Essentially, wherever an application demands servo-like performance—precise speed holding, fast response, or controlled torque—from a robust, industrial AC drive platform, the installation of the 1336-L4​ encoder feedback board is the enabling technology.