CASR 50-NP/SP1 Closed-Loop Fluxgate Current Sensor

CASR50-NP/SP1 Product Overview

The CASR 50-NP/SP1 is a high-performance closed-loop fluxgate current sensor from LEM, the world leader in current sensing technology. Combining advanced fluxgate measurement with closed-loop compensation, this sensor is purpose-built for demanding industrial current detection applications. It accurately measures DC, AC, and pulsed currents while providing galvanic isolation between the primary and secondary circuits.

With a nominal current rating of 50 A and a measuring range up to ±150 A, the CASR 50-NP/SP1 delivers an ultra-fast 300 ns response time and an excellent linearity of ±0.1 %. It provides reliable, precise current feedback for power supplies, motor drives, and industrial automation systems.

CASR50-NP/SP1 Key Advantages

Closed-Loop Fluxgate Technology for Superior Accuracy

The closed-loop (compensated) fluxgate architecture offers extremely low temperature drift and outstanding immunity to external interference compared to traditional open-loop Hall sensors. With a linearity of ±0.1 % and an accuracy of ±0.8 %, it delivers trustworthy measurement results whether in harsh industrial environments or sensitive laboratory settings.

Blazing Fast Response for High-Frequency Dynamics

A 300 ns response time makes the CASR 50-NP/SP1 ideal for high-frequency PWM motor drives, switch-mode power supplies, and other dynamic applications. Its frequency bandwidth spans DC to 300 kHz, capturing every detail from steady-state DC to high-frequency components – ensuring robust real-time current loop feedback.

Single-Supply Operation for Simplified Design

The sensor operates from a single 4.75 V ~ 5.25 V supply, eliminating the need for complex dual-rail designs. This greatly simplifies peripheral circuitry and reduces system power consumption. With a maximum supply current of only 20 mA, it is particularly friendly to battery-powered or low-power devices.

Wide Temperature Range for Reliable Operation

Rated for operation from -40 °C to +105 °C, the CASR 50-NP/SP1 maintains stable performance whether in frigid outdoor environments or hot industrial workshops.

CASR50-NP/SP1 Technical Specifications

CASR50-NP/SP1 Typical Applications

With its high accuracy, fast response, and wide temperature range, the CASR 50-NP/SP1 is ideal for:

AC variable speed and servo motor drives – precise current-loop feedback for enhanced control

DC motor drive static converters – stable and reliable current detection

Uninterruptible power supplies (UPS) – safeguarding critical load power quality

Switch-mode power supplies (SMPS) – real-time monitoring of high-frequency currents

Solar inverters – current measurement in renewable energy systems

Battery-powered equipment – low power consumption extends battery life

Welding equipment power supplies – withstands rugged operating conditions

Why Choose the CASR 50-NP/SP1?

In industrial current sensing, accuracy, speed, and reliability are non-negotiable. The CASR 50-NP/SP1 condenses decades of LEM expertise into a compact module – the closed-loop fluxgate core ensures superior precision and stability, the 300 ns response meets the most demanding dynamic requirements, and the single-supply design combined with a wide temperature range makes system integration simpler than ever.

Whether you are upgrading existing equipment or developing a new highperformance product, the CASR 50-NP/SP1 is the definitive choice for your current sensing needs.