How LEM Current and Voltage Transducers Work

Modern energy and industrial systems require precise real-time measurement of current and voltage. LEM transducers, both current and voltage, play an important role in monitoring and controlling the flow of energy in electrical systems. They enable safe device management, network parameter control, and increased energy efficiency of systems.

Current and voltage transducers are used in many areas, from industrial automation to photovoltaic and wind systems, as well as in high-voltage and high-current power networks. Their main task is to convert current or voltage from an electrical system into a measurement signal proportional to the measured values. This allows systems to respond accurately to changes in real time, which is crucial for the safety and reliability of machines and devices.

What are current and voltage transducers?

A transducer is a measurement element that allows monitoring of current or voltage in direct and alternating current systems (DC and AC). LEM transducers operate based on various technologies, including the Hall effect method. In the case of Hall-effect transducers, current can be measured without direct contact with the conductor. Other transducers use ferromagnetic cores or isolation technologies, depending on the application.

Current transducers measure the current flowing through a conductor and convert it into an output signal proportional to the current. They are used for monitoring motor currents, controlling power in industrial systems, and in energy management devices. Voltage transducers provide information about voltage in the network or power system, allowing precise control and protection against overloads. Depending on the technology, a voltage transducer may use resistive dividers, isolation transformers, or other isolation solutions.

Types of LEM transducers

In practice, different types of transducers are distinguished depending on the application and type of current:

• DC current transducers – for measuring direct current in photovoltaic systems, energy storage, and electric vehicle charging.
• AC and DC current transducers – allow measurement of both alternating and direct current, with accuracy depending on the technology used (Hall, current transformer).
• Voltage transducers – used in power networks, automation systems, and power electronics, providing a signal proportional to voltage.
• High-current transducers – for use in galvanic and energy processes with very high currents. Only specialized models support values reaching hundreds of kiloamperes.

How do current and voltage transducers work?

The operating principle of a current transducer is based on converting the flowing current into an electrical signal proportional to its value. In systems based on the Hall effect, the current generates a magnetic flux, which is detected by a Hall sensor. The transducer then produces an output signal that can be read by automation or measurement systems.

Voltage transducers work on a similar principle, converting voltage into a proportional signal, allowing control of energy flow in real time. In both cases, it is important that the transducer is selected appropriately for the measured values and type of current in the system (AC or DC).

Applications of LEM transducers

LEM transducers are used in a wide range of industrial and energy applications:

• Industrial automation systems – monitoring currents and voltages in machines, devices, and production lines, ensuring operational safety and system reliability.
• Energy and power systems – monitoring currents in AC and DC networks, energy storage systems, wind farms, and photovoltaic plants.
• Electric vehicle charging – precise current measurement enables optimized charging and battery energy management.
• Power electronics and supply systems – transducers provide measurement signals for control and protection systems, increasing efficiency and safety of machines and devices.
• Monitoring and control systems – allow detection of anomalies, supervision of current and voltage flow, and optimization of energy consumption in real time.

Transducer parameters

When selecting a current or voltage transducer, attention should be paid to:

• Current or voltage range – to ensure the transducer can measure actual values in the system.
• Measurement accuracy – affects output signal precision and control safety.
• Electromagnetic immunity – important in industrial environments and automation systems.
• Type of output signal – proportional to the system current or voltage.
• Transducer applications – direct current, alternating current, high currents, or high voltages.
• Reliability and durability – in industrial or energy processes where operation under harsh conditions is standard.

Summary

LEM current and voltage transducers are indispensable elements in automation, energy, and power electronics systems. They enable monitoring of current and voltage flow, precise system control, and increased energy efficiency. Their use in AC and DC systems, high currents, and industrial environments ensures reliable operation of machines, devices, and power systems.

LEM transducers provide accuracy, reliability, and immunity to interference, which is crucial for the safety of devices and electronic components. Their versatility makes them suitable for industrial systems, energy management, photovoltaics, and energy storage applications.

We invite you to explore our offer – we provide a wide selection of current and voltage transducers, ideal for industrial and automation applications. See how our solutions can enhance the safety and efficiency of your systems.