ABB low inrush current motors

ABB has identified the most common requirements for low inrush current (LIC) motors and created a set of pre-calculated motors based on enhanced designs.

The set of pre-calculated low inrush current motors are designed to meet the requirements of extruder, pump and compressor applications. The motors are said therefore combine the excellent reliability of ABB’s high-voltage modular induction motor platform (type AMI) with the best-possible performance in their given application.

LIC motors are used to minimise disturbances in weak supply networks. When a regular motor is started in a weak network, the high starting current can cause a voltage drop that may disrupt the operation of other equipment. Weak networks are often found in remote locations and are most common in sectors such as COG, marine, mining and quarrying.

The company’s LIC technology is based on improved rotor designs, where the rotor bars are manufactured from carefully selected high resistivity copper alloys and the bar width and shape are varied in order to deliver the required motor performance. As a result the starting current is only 3.5-4.5 times nominal, which can be compared with figures of up to seven times nominal for regular motors.

The standard LIC range consists of 11 kV motors in 2-, 4- and 6-pole versions and frame sizes 560-900. The maximum power output is 4-11 MW, depending on the target application. The motors are supplied with non-sparking (Ex nA) or pressurised (Ex p) protection for use in explosive atmospheres.