LV100-250/SP6 High-Precision Closed-Loop Hall-Effect Voltage Transducer

LV100-250/SP6 Brand: LEM – Global Leader in Electrical Measurement

In industrial automation and power electronics, the accuracy and response speed of voltage acquisition form the cornerstone of closed-loop control, determining the dynamic performance and operational stability of your entire system. The LV100-250/SP6 voltage transducer, built by Switzerland’s LEM (pioneer of closed-loop Hall-effect technology), is a high-performance measuring component carefully engineered for 250V-class industrial equipment. With its outstanding cost-performance ratio and high accuracy, it is widely trusted in variable frequency drives, servo drives, UPS systems and many other applications – by customers worldwide.

LV100-250/SP6 Product Overview

The LV100-250/SP6 is a high-accuracy closed-loop Hall-effect voltage transducer from LEM’s LV100 series, designed for electronic measurement of DC, AC, and pulsed voltages. Using advanced closed-loop Hall-effect compensation technology, it has a primary nominal voltage of 250 V and a maximum measuring range extending to ±375 V. Whether monitoring the DC bus of a 250V-class VFD, providing precise feedback for a servo drive, or detecting voltage in a UPS system, this transducer handles the task with ease.

The transducer provides complete electrical isolation between the primary and secondary circuits, with a tested isolation voltage of 6 kV @ 50 Hz for 1 minute. This ensures the safety of downstream measurement circuits and eliminates ground-potential interference and electric shock risks.

This model features an extremely fast response time of 75 µs, reaching 90% of the nominal voltage in just 75 microseconds. What does this response speed mean? When a voltage transient or spike occurs in your equipment, the LV100-250/SP6 captures the anomaly almost instantaneously – from occurrence to detection in less than 0.1 milliseconds – giving your downstream overvoltage protection and dynamic control systems a critical response window.

After years of industrial field testing, the LV100-250/SP6 operates reliably in tens of thousands of installations worldwide – from automated production lines on factory floors to UPS systems in data centers, from robotjoint servo drives to precision welding equipment. It consistently delivers stable, dependable performance for demanding voltage measurement tasks.

LV100-250/SP6 Key Advantages & Technical Features

✅ 1. Industry-Leading Measurement Accuracy

Using closed-loop Hall-effect compensation technology, the transducer achieves an overall accuracy of ±0.7% and linearity better than 0.1%. It provides consistent, distortion-free signals across the entire rated measuring range, ensuring accurate and reliable results under both wide input voltage swings and complex load variations. Moreover, for long-term use, the offset current is only ±0.3 mA – meaning extremely low deviation under zero-input conditions, fundamentally safeguarding measurement accuracy across the full scale.

✅ 2. Microsecond-Class Fast Response

With a response time of only 75 µs, this model ranks among the fastest in its class. When the system suffers voltage surges, spikes, or sudden load changes, it feeds the signal back to the control unit at near-real-time speed, seizing the critical “golden response window” for your control loop.

✅ 3. Very Low Temperature Drift

Superior manufacturing processes give this model excellent long-term stability. Zero drift is only ±0.2 ~ ±0.3 mA/°C. Combined with a wide operating temperature range of 0°C to +70°C, the long-term stability is outstanding. Whether in hot workshops, sealed cabinets, or outdoor environments, measurement accuracy remains consistently high without frequent recalibration.

✅ 4. High Noise Immunity & Strong Insulation

The insulating plastic case meets UL 94-V0 (highest flame retardancy rating). The closed-loop compensation architecture provides superior common-mode and electromagnetic interference rejection, ensuring stable and error-free operation even in “electromagnetic heavy environments” filled with inverters and highpower switching devices – no additional shielding required.

✅ 5. Integrated Primary Resistor – Simplifies Design

The primary resistor (R1) is integrated inside the housing, simplifying external circuitry, making PCB layout more compact, and speeding up assembly. This significantly reduces your BOM cost and engineering effort. The total weight is only 850 grams, enabling high-density system designs without sacrificing performance.

LV100-250/SP6 Technical Specifications

LV100-250/SP6 Wide Range of Applications

With its ±375 V measuring range, ±0.7% accuracy and 6 kV isolation rating, the LV100-250/SP6 is ideal for many industrial applications:

✔ AC variable speed drives
Precision monitoring of inverter DC-bus voltage for efficient, smooth motor operation and extended equipment life.

✔ Servo motor drive systems
Lowlatency, high-accuracy voltage feedback for servo drives, ensuring precise position and speed control – directly affecting motion performance in automation and robotics.

✔ Static converters for DC motor drives
Reliable voltage measurement in rectification and inversion stages, keeping the DC link stable and controllable.

✔ Uninterruptible power supplies (UPS)
Realtime monitoring of input/output voltage in 380V/400V systems, ensuring critical loads receive stable power even during grid disturbances – safeguarding the operational safety of data centres, hospitals and other key infrastructure.

✔ Welding equipment power supplies
Accurate voltage detection under high-voltage, high-transient conditions for consistent weld quality.

✔ Industrial robots, automated production lines, battery-powered equipment
Suitable for applications with stringent requirements for noise immunity, long-term reliability, and wide temperature tolerance.

✔ Traction & railway auxiliary equipment
Adapted to traction applications such as single-phase or three-phase inverters, auxiliary converters and battery chargers that demand high insulation and high reliability.