Condition-based monitoring (CBM) for electrical motors

Condition-based monitoring (CBM) integrated into premium Danfoss drives has revolutionized the way these drives monitor electric motors for faults and potential failures. With breakthrough technology implemented at the drive level, CBM offers advanced features such as motor stator winding monitoring, vibration monitoring, wear-out monitoring of bearings, load envelope (torque) monitoring, and cavitation detection, all in one comprehensive package.

One of the key aspects of condition monitoring using Danfoss drives with integrated CBM is the ability to provide early detection and notification of motor isolation faults. Danfoss drives have embedded current transducers, eliminating the need for external sensors, temporary installation end labor to get the motor “talking” to the monitoring system. These drives run a "baseline measurement" to learn the baseline values for each monitoring function. Based on the baseline, warning and alarm thresholds are created to compare the actual values during operation.

Motor stator winding monitoring is a critical function of integrated CBM. By using current signature analysis in the drive, turn-to-turn short winding fault detection is possible. This early warning system helps detect motor failure by identifying faults in the winding insulation allowing planning of maintenance and preventing sudden breakdowns. Advanced algorithms in the drive eliminate false warnings caused by motor imperfections or grid conditions. This feature is supported for asynchronous (IM) and permanent magnet (PM) motors, parallel motors, and works with output filters installed. It can be especially beneficial for motors operating in harsh environments with high humidity and high temperatures, as well as for older motors with fatigued winding insulation.

The benefits of CBM for motors are significant. Monitoring performance using CBM provides a simple and cost-effective way to obtain machine data for smart maintenance decisions. With CBM, there is no need for specialized expertise, as existing user interfaces are supported. CBM can be used in a wide range of applications and motor ratings. It’s also reassuring to know that CBM operates independently of the cloud, using edge computing in the drive, ensuring data privacy and security.

Enable your maintenance decisions based on application data. By enabling early warnings and notifications, CBM increases production uptime by allowing operators to take action on alerts, to perform necessary remedial actions before an unscheduled breakdown occurs. It helps identify damaged motor windings, increasing vibration levels, squealing bearings, and unusual torque values. CBM also allows for the transition from scheduled maintenance to predictive maintenance, increasing the efficiency and effectiveness of maintenance strategies. It is a cost-effective solution compared to external complex systems offered by third parties.

Example: The ability to prevent unexpected breakdowns is especially significant in an aseptic manufacturing environment. One pharmaceutical company conducted tests to prove that intelligent Danfoss drives with integrated condition-based monitoring provide reliable ventilation in an aseptic environments. The drives help to prevent downtime with real-time system monitoring and customizable instant alarms, which provide an early warning enabling operators to take preventive action.

CBM is especially suitable for remote locations or devices that are difficult to access. With permanent monitoring, potential faults can be detected and addressed before they result in motor failure and production downtime. By taking maintenance strategies to the next level with CBM, industries can increase their application uptime, reduce maintenance costs, and enhance overall operational efficiency.

Read more about enhancing condition monitoring with remote monitoring