In depth Analysis and Application Guidelines for ABB QABP Low Voltage High Efficiency Variable Frequency Special Motor Technology
Introduction: Variable frequency drive solution for the Chinese market
With the continuous improvement of energy efficiency and automation control requirements in China's industrial sector, variable frequency speed regulation technology has become the core of energy-saving transformation and process optimization. ABB Group has developed and launched a new generation of QABP series low-voltage high-efficiency variable frequency dedicated three-phase asynchronous motors specifically for the Chinese market in response to this trend. This series of motors not only complies with international IEC and Chinese GB standards, but also has high energy efficiency levels of IE2 and IE3. It integrates ABB's advanced technology in motor manufacturing and variable frequency control, aiming to provide reliable, efficient, and flexible drive solutions for industries such as papermaking, metallurgy, mining, lifting, rubber and plastic, textile, printing and packaging, food and beverage, chemical, water treatment, and HVAC.
Product Overview and Core Standards
The QABP series motor adopts a fully enclosed three-phase squirrel cage design with a sturdy structure, suitable for harsh industrial environments. Its design and manufacturing strictly follow the following international and national standard systems to ensure the global universality and reliability of the product:
Electrical standards: IEC 60034 series (covering general requirements, efficiency measurement, protection level, etc.), GB/T 755 (Rotating Electrical Machinery Rating and Performance).
Mechanical standards: IEC 60072 (machine base dimensions), GB/T 4772.1 (dimensional tolerances).
Energy efficiency standards: Meet the efficiency levels of IE2 and IE3 in IEC 60034-30-1 and Chinese GB 18613 standards.
Quality and Environmental System: The production unit has obtained ISO 9001 Quality Management System and ISO 14000 Environmental Management System certifications.
The core innovation of the motor lies in its optimized design for variable frequency operation: using high-grade corona resistant composite enameled wire, combined with ABB's proprietary variable frequency control technology, significantly improves the reliability of the winding insulation system, and effectively suppresses shaft current problems caused by variable frequency power supply, thereby greatly reducing the risk of winding breakdown and bearing damage. This design provides the motor with extremely high stability and long lifespan when operating over a wide frequency range.
Electrical Design: Insulation, Temperature Rise, and Operational Adaptability
The electrical performance of a motor is the foundation for ensuring its long-term stable operation. The QABP series embodies a high degree of engineering consideration in electrical design.
1. Insulation system and safety margin
The motor adopts F-grade (155 ℃) insulation material, but is evaluated according to B-grade (130 ℃) temperature rise. This design creates a temperature rise safety margin of up to 25 ℃. This margin allows the motor to withstand overload for a short period of time, operate at temperatures or altitudes higher than standard, or adapt to wider voltage and frequency fluctuations. From a lifespan perspective, for every 10K decrease in the operating temperature of the insulation system, its expected lifespan can be significantly extended.
2. Operating environment and derating factor
The standard motor design is suitable for a maximum ambient temperature of 40 ℃ and a maximum altitude of 1000 meters. If the operating conditions exceed this range, the motor output power needs to be downgraded according to the provided kHT power conversion factor table. For example, at an altitude of 2000 meters and an ambient temperature of 45 ℃, the derating coefficient is about 0.90.
3. Overload capacity
According to the IEC 60034 standard, QABP motors are capable of withstanding 1.5 times the rated current for up to 2 minutes at rated voltage and frequency, demonstrating excellent short-term overload capability.

Mechanical Design: Bearings, Seals, and Structural Strength
A reliable mechanical structure is the guarantee for the motor to withstand various loads.
1. Bearing configuration and service life
The standard configuration of the motor is a single row deep groove ball bearing, and an axial locking bearing is standard on the drive end (D end) to withstand a certain axial force. For frame sizes 71-250, the motor adopts a lifetime lubricated enclosed bearing, filled with high-quality grease, and the bearing life can reach about 40000 hours in typical applications. Larger machine bases use self-lubricating bearings. The bearing selection table also provides optional cylindrical roller bearing solutions to cope with heavier radial loads.
2. Shaft seal
According to the base number and pole number, the motor is equipped with standard axial (RB type) or radial (TC type) seals, effectively preventing external pollutants from entering the bearing chamber and adapting to different industrial environments.
3. Allowable load on the shaft
This is the key data for mechanical design, which directly affects the selection of motors in mechanical transmission applications such as belts and gears. The manual provides detailed tables listing the allowable radial force at zero axial force and the allowable axial force at zero radial force, calculated based on bearing life of 20000 hours and 40000 hours (ambient temperature 25 ℃, 50Hz). When the load acts on different positions of the shaft extension, the allowable force can be converted by a given formula. For 60Hz operation, the values in the table need to be reduced by 10%. If there are both radial and axial composite loads, please consult ABB for specific data.
4. Junction box and grounding
The standard junction box has a protection level of IP55 and is usually installed on the top of the motor's D end. It can also be installed on the left or right side according to ordering requirements. The junction box for machine base numbers 71-132 can rotate 4 × 90 °, and the junction box for machine base numbers 160-355 can rotate 2 × 180 °, making it easy for cables to be connected from different directions. Provide reliable grounding terminals inside the junction box to ensure safety.
Variable frequency drive: compatibility, selection, and key considerations
As a dedicated motor for frequency conversion, its matching with the frequency converter is crucial. This chapter provides in-depth application guidance.
1. Basic principles of selection
When using a frequency converter for power supply, the non sinusoidal output voltage/current will increase the additional losses, vibrations, and noise of the motor. Therefore, the motor power must be selected correctly according to the specific instructions of the frequency converter. We recommend using ABB's DriveSize selection tool, which is based on comprehensive type test data. If selecting manually, it is necessary to ensure that the maximum torque of the motor throughout the entire working cycle is at least 30% higher than the load torque to maintain stable operation.
2. Winding insulation and voltage stress
The high du/dt pulse voltage output by the frequency converter poses a severe challenge to the insulation of the motor. The manual provides clear insulation and filter selection guidelines based on grid voltage and frequency converter type:
500V<Ua ≤ 600V: "ABB variable frequency insulation"+du/dt filter can be selected, or "ABB variable frequency reinforced insulation" can be directly selected (variable code 405).
600V<Ua ≤ 690V: "ABB variable frequency reinforced insulation" (variable code 405) must be selected and a du/dt filter must be installed at the output end of the frequency converter.
The allowable peak phase ground voltage for motor terminals is 1300V for "ABB variable frequency insulation" and 1800V for "ABB variable frequency reinforced insulation".
3. Bearing current protection
Bearing current is a common issue in variable frequency drives, which may cause early damage to bearings. The QABP series responds to:
Power ≤ 100 kW: Usually no special measures are required.
Power ≥ 100 kW or machine base size 315-355: standard configuration with ceramic plated shaft, optional non drive end insulated bearing (variable code 701).
Power ≥ 350 kW: It is recommended to use both non drive end insulated bearings and install a common mode filter at the frequency converter end.
4. Cable laying and EMC
To reduce electromagnetic interference and ensure system reliability, it is strongly recommended to use shielded symmetrical cables and EMC cable connectors that provide 360 ° overlap (variable code 704). For motors with a base size of 280 and above, if the motor and load equipment are not installed on a common metal base, additional potential balancing connections must be made between the motor base and the driven machinery.
Technical data, appearance and selection guide
The core part of the manual provides a detailed technical parameter table for motors with different pole numbers (2P, 4P, 6P, 8P) and frame sizes (71-355) under IE2 and IE3 energy efficiency levels. including:
Rated data: output power, speed, efficiency, power factor, current, torque.
Performance parameters: starting current ratio, locked rotor torque ratio, maximum torque ratio.
Physical parameters: moment of inertia, weight, sound pressure level.
The product ordering code is a 14 character string that systematically encodes the motor type, frame number, pole number, serial number, installation method (such as IM B3 foot installation, IM B5 flange installation), voltage frequency code, and product generation code. Users only need to provide key parameters according to the example to generate unique product codes, and can attach variable codes to achieve special configurations such as special insulation, special bearings, special paint, brakes, encoders, etc.
The external dimension diagram and table provide detailed installation dimensions for all standard installation methods (IMB3, IMB5, IMB14, IMB34), providing precise basis for equipment integration and space planning.
