ABB QABP Low Voltage High Efficiency Variable Frequency Motor Application Guide

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.