LV 25-P
500V rated isolated voltage transducer with 0.8% accuracy for industrial power electronics applications
Product Overview
Description
The LV 25-P is a compact isolated voltage transducer designed for measuring DC, AC, and pulsed voltages up to 500V. It combines an integrated primary resistor with Hall effect isolation technology to provide safe, accurate voltage measurement in power electronics applications.
Featuring 0.8% accuracy, 2.5kV isolation voltage, and 10kHz bandwidth, the LV 25-P delivers reliable performance for inverter monitoring, power supply feedback, and industrial control systems. The sensor operates from a single 12-15V supply and provides instantaneous voltage output proportional to the measured voltage.
The LV 25-P is widely used in applications such as PV inverter DC bus monitoring, motor drive DC link measurement, UPS battery voltage sensing, and power supply output feedback. Its compact design and panel-mount capability simplify integration into existing equipment.
Product Series
LV
Primary Application
Voltage Transducers
Key Features
- High efficiency and reliability
- Optimized for industrial applications
- Comprehensive technical support
- Available from stock
Specifications
| Rated Voltage | 500V |
|---|---|
| Measurement Range | ±1500V |
| Primary Resistance | 12 kΩ |
| Supply Voltage | ±12V to ±15V |
| Output Type | Instantaneous Voltage |
| Accuracy | ±0.8% |
| Response Time | 40 μs |
| Bandwidth | 10 kHz |
| Isolation Voltage | 2.5 kV |
| Operating Temperature | -40°C to +85°C |
Applications
Motor Drives
Variable frequency drives and servo motor controls
Power Supplies
SMPS, UPS, and industrial power systems
Renewable Energy
Solar inverters and wind turbine converters
EV Charging
Electric vehicle charging stations
FAE Expert Insights
"LV 25-P is an excellent choice for industrial applications."
— Field Application Engineer, BeiLuo
Frequently Asked Questions
What is the primary resistance of LV 25-P and why does it matter?
The LV 25-P has an integrated primary resistance of 12kΩ. This resistance is crucial because: 1) It determines the input current at a given voltage (I = V/R), which affects power dissipation; 2) Along with the Hall sensor characteristics, it determines the overall transfer ratio; 3) It affects the input impedance seen by the measured circuit. At 500V rated voltage, the primary current is approximately 42mA, resulting in about 21W power dissipation in the internal resistor. This significant power dissipation requires thermal consideration in the design. The 12kΩ value provides a good balance between power dissipation and measurement performance for the 500V rating.
The 12kΩ primary resistance results in significant power dissipation (21W at 500V). Ensure adequate ventilation or heatsinking in your design. For lower dissipation, consider adding external series resistors to share the power load.
Can LV 25-P measure voltages above 500V?
The LV 25-P can measure voltages beyond its 500V rated value, but with important considerations: 1) The measurement range extends to ±1500V with reduced accuracy; 2) Continuous operation above 500V increases power dissipation and may cause overheating; 3) For sustained high-voltage operation, external series resistors should be added to share power dissipation; 4) The isolation rating (2.5kV) sets the absolute maximum safe voltage. For applications requiring continuous measurement above 500V, consider using the LV 100 (1000V rated) or adding appropriate external resistors. Always ensure thermal design accommodates the power dissipation at operating voltage.
For occasional peaks up to 1000V, LV 25-P can be used. For continuous operation above 500V, use LV 100 (1000V rated) or add external series resistors to share power dissipation and prevent overheating.
How do I interpret the LV 25-P output signal?
The LV 25-P provides a differential voltage output proportional to the measured primary voltage. The nominal conversion ratio is typically 2500:1000 (consult specific datasheet for exact ratio), meaning at 500V input, the output is approximately 200mV. The output is bipolar, representing both positive and negative input voltages. For a ±15V supply, the output typically centers around 0V with positive and negative excursions. To use the output: 1) Connect to a differential amplifier or ADC with appropriate input range; 2) Scale the output based on the conversion ratio to calculate input voltage; 3) Consider adding filtering if noise is present; 4) Ensure load impedance meets specifications (typically >10kΩ). The datasheet provides detailed transfer characteristics and connection diagrams.
Use a differential amplifier or instrumentation amplifier to process the LV 25-P output. Scale the output to match your ADC input range. For noise-sensitive applications, add a low-pass filter with cutoff frequency above your signal bandwidth but below switching noise frequencies.