VFD Monitoring
Summary
Verivolt provides reliable sensing solutions for Variable Frequency Drive (VFD) monitoring and testing by offering high-bandwidth, low-noise, and fully isolated voltage and current sensors. Our sensors are engineered to meet the demanding requirements of VFD applications, ensuring accurate, safe, and stable performance in high-frequency and high-voltage environments.
Product in Use
The Challenge:
Voltage and Current Monitoring in VFD Systems
Variable Frequency Drives (VFDs) are widely used across various industries to optimize motor performance, enhance energy efficiency, and improve process control. VFDs are commonly found in manufacturing, HVAC systems, water and wastewater treatment, oil and gas, among many others. These applications often involve demanding electrical and environmental conditions, including high currents and voltages required to power motors. Additionally, such environments may expose equipment to high ambient temperatures, electrical noise from switching elements, and mechanical vibrations. Monitoring voltage and current in VFD applications is critical for performance verification, troubleshooting, and preventive maintenance.
Most modern VFDs have embedded sensors that measure current and voltage internally. These internal measurements are primarily used for control logic, protection mechanisms, and sometimes diagnostics. However, there are several good reasons to use independent current and voltage sensors to monitor the motor or load, even if the VFD already has built-in sensing, such as:
Accuracy and Signal Quality
Accurate Power Measurement
Advanced Analysis & Logging
Third-Party Compliance & Certification
Retrofit & Test Bench Applications
How do Verivolt’s Sensors Address these Challenges?
Verivolt sensors used in this application field present the following characteristics.
Recommended Verivolt Sensors for VFD Application
Voltage Measurement
- IsoBlock V-4C: (up to 300 KHz – custom) A 4-channel, differential-input, high-bandwidth isolated voltage suitable for capturing line-to-line voltages with ranges from 2V up to 1500V. The IsoBlock V-4C sensor is ideal to monitor the VFD output phases with up to 0.1% accuracy.
- Isoband V (up to 8 MHz): This sensor offers a unique combination of high-isolation, high voltage measurement and high-bandwidth, making it a perfect choice for measuring fast transients, PWM switching and high-frequency signals with 0.2% accuracy.
Your application requires more than 8MHz bandwidth? Try our high-bandwidth, non isolated sensors:
- Entube DE-HB (up to 20 MHz): A high bandwidth differential voltage sensor
- Entube Z (up to 50 MHz): A compact, single ended voltage sensor with the highest bandwidth
Current Measurement
- IsoBlock I-ZF: An isolated, contactless current sensor that uses a zero-flux technique for measurements with up to 0.01% accuracy. Ideal for monitoring both input and output currents and identifying overcurrent or load imbalance. Available from 50A to 2000A ranges.
- IsoBlock I-ST: Isolated shunt-based current sensor designed for low to mid range input. Enables simultaneous and isolated monitoring of all three motor phases to detect unbalances. Input ranges available from 100mA to 100A.
Conclusion
Verivolt delivers precision voltage and current sensing solutions tailored for the dynamic requirements of VFD systems. Our sensors provide the performance, accuracy, and isolation needed to ensure optimal motor monitoring. Visit our website to explore products designed to meet the evolving challenges of this industry.
