Load Monitor in Industry: Intelligent Motor Monitoring for Maximum System Availability

In modern industrial plants, it's not just the quality of the mechanics that determines productivity and safety – it's the intelligent monitoring of electric motors. 

A professional load monitor measures the active power of electric motors and turns the motor itself into a sensor. This is exactly where we come in – with intelligent products in the field of load monitoring relays and active power measurement.    

Our partner TELE Haase is the manufacturer with the largest range of load monitors.

For companies, this means:

• Increased plant availability
• Reduced maintenance
• Higher process reliability

The motor as a sensor –

Why is power measurement crucial?

A surprisingly large number of conclusions can be drawn from the load state of an electric motor:

• Fill levels
• Loading status
• Viscosity of media
• Wear and tear
• Blockages or mechanical damage

 Your advantage:

No additional sensors and complex wiring, as well as reduced maintenance.

Why is simple current monitoring not enough?

Many systems still use simple current monitoring relays. The problem →  Apparent current is measured, not actual mechanical power. In the undeloaded range, current remains relatively high due to magnetization. Current is voltage-dependent → Misinterpretation in case of undervoltage 

Conclusion: Simple current monitoring is only suitable for extreme conditions (e.g., blockages).

Measurement principles compared:

• Power factor (cos φ):
  • Meaningful in the underload range
  • Less sensitive in the nominal and overload range
• Power measurement:
  • Directly proportional to shaft power
  • Precise over the entire operating range
  • Best basis for reliable monitoring

Therefore, power measurement is the most precise and practical method.

Technical advantages of modern load monitors

Direct measurement up to 16 A (current transformers only needed for higher currents)

• Suitable for 1- and 3-phase systems
• Voltages up to 690 V
• Also usable after frequency converters
• Adjustable trip and startup times
• Separate switching thresholds
• Thermistor monitoring optional
• Power failure monitoring
• Fault memory
• Switching outputs or analog outputs (e.g. 4–20 mA)
  

Economic benefits for companies

• Detect errors early
• Log measurement data
• Initiate control functions automatically
• Avoid production downtimes

Load Monitors in the Energie-Shop