The Allen-Bradley 1334-CJB is a high-performance, industrial-grade AC drive belonging to the Bulletin 1334 family of Adjustable Frequency Motor Drives. Designed to control the speed and torque of three-phase induction motors, the 1334-CJB was a cornerstone of industrial automation for years, known for its ruggedness and reliability in heavy-duty applications. The “CJB” designation refers to a specific power rating and enclosure configuration, providing precise pulse-width modulated (PWM) power to improve motor efficiency and process control.

Product Parameters and Technical Specifications

The 1334 series is engineered to provide consistent torque control across a wide speed range.

• Model Number: 1334-CJB
• Series: Bulletin 1334
• Input Voltage: 460V AC, 3-Phase, 50/60 Hz
• Output Voltage: 0 to Rated Input Voltage
• Output Frequency: 0–120 Hz (Adjustable)
• Control Method: Pulse Width Modulation (PWM)
• Enclosure Type: NEMA Type 1 (IP20) or Open Chassis (depending on final suffix)
• Horsepower Rating: Typically 5 HP (Refer to the specific nameplate for “CJB” amperage capacity)

 

Product Datasheet Summary

The 1334-CJB datasheet highlights its modular internal construction, which simplifies component replacement and troubleshooting. It utilizes power bipolar transistors or early IGBT technology to provide a clean output waveform to the motor. The drive features integrated protection against over-voltage, under-voltage, and instantaneous over-current. It also includes an adjustable electronic overload protection system, eliminating the need for external thermal relays in many configurations.

 

Country of Origin

This drive was manufactured in the USA, adhering to Allen-Bradley’s (Rockwell Automation) rigorous quality standards for industrial power electronics.

 

Application Fields

The Bulletin 1334 drives are found in a wide variety of demanding sectors:

• HVAC Systems: Controlling large centrifugal fans and water pumps to reduce energy consumption.
• Material Handling: Managing conveyor belt speeds in warehouses and distribution centers.
• Food & Beverage: Operating mixers, grinders, and bottling lines where precise speed control is required.
• General Manufacturing: Powering machine tools and assembly line equipment.

 

Product Usage Instructions

1. Mounting: Install the drive in a vertical orientation with sufficient clearance (typically 6 inches above and below) for proper airflow and cooling.
2. Wiring: Connect the 3-phase AC input to terminals L1, L2, and L3. Connect the motor leads to U, V, and W. Ensure all ground connections are bonded to a common ground bus.
3. Parameter Setup: Use the integrated or remote DIP switches and potentiometers (on earlier versions) or the digital programming interface to set the base frequency and acceleration/deceleration ramps.
4. Safety: Always wait at least 5 minutes after disconnecting power before opening the unit to allow the DC bus capacitors to discharge to safe levels.

 

Technical Description

The 1334-CJB operates by first rectifying the incoming AC line voltage into a stable DC bus. This DC power is then processed by an inverter stage using PWM logic to recreate a variable frequency and variable voltage AC output. This allows the motor to maintain constant volts-per-hertz (V/Hz), ensuring that the motor produces constant torque from low speeds up to the base frequency. The “C” in the model number typically indicates the 460V voltage class, while the “JB” indicates the specific frame size and current rating.

 

Q&A – Frequently Asked Questions

Q: Is the Bulletin 1334 still in active production? A: No, the Bulletin 1334 is a legacy product. It has been succeeded by the PowerFlex series (such as PowerFlex 755 or 525). However, many 1334 units remain in service due to their high durability.

Q: Can I use this drive for a 230V motor? A: No, the 1334-CJB is designed for 460V input and output. Running a lower voltage motor on this drive will likely result in insulation failure or motor burnout.

Q: What does a “Fault” light on the front panel mean? A: A fault light indicates the drive has tripped to protect itself. Common causes include “Overcurrent” (mechanical jam in the motor) or “Overvoltage” (excessive regeneration during fast deceleration).

Q: Where can I source replacement parts for the 1334-CJB? A: You can find the Allen-Bradley 1334-CJB and related legacy renewal parts through specialized industrial automation inventory providers.

 

Recommended Similar Models

1. Allen-Bradley 1334-CKB – A higher horsepower version in the same 460V family.
2. Allen-Bradley 1336-B005-EAD – The immediate successor series (Bulletin 1336 PLUS) which replaced the 1334.
3. Allen-Bradley 1334-AAB – The 230V AC version of the 1334 drive family.
4. Allen-Bradley PowerFlex 70 – A modern digital alternative for upgrading legacy 1334 installations.
5. Allen-Bradley 1336-CONV – Conversion kits and parts often used when maintaining 1334/1336 drive systems.