创新
为了支持市场对各种电气和机械的需求，LEM开发了一系列技术，包括：霍尔效应开环技术、霍尔效应闭环技术、磁通门技术，包括 :
- “IT-型”、
- “C-型”、
- “CTSR型”、
- “CAS-CASR-CKSR型”
- 和“ITC型”
绝缘数字技术，包括“DVL&DVM&DV型” 空芯技术包括Rogowski线圈，PRiME™和电流互感器型，虽然满足大部分应用需求的最好的解决方案是提供一个标准的基于其中一个技术传的感器，但LEM完全能够开发定制的解决方案，来满足客户的具体要求。
创新
- Closed Loop Current Transducers
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- Closed Loop Fluxgate C type
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- Closed Loop Fluxgate CAS-CASR-CKSR Type
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- Closed Loop Fluxgate CTSR type
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- Closed Loop Fluxgate IT type
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- Closed Loop Fluxgate ITC type
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- Closed Loop Voltage Transducers
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- DV & DVL & DVM Type Voltage Transducers
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- Open-Loop Current Transducers
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- PRiME Current Transducers
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- Rogowski Current Transducers
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- Split Core Current transformers AT & TT Type
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Current Transducers
LEM is a leading supplier of current transducers (also called current sensors), offering a wide range of galvanically isolated transducers that have become industry standards. The broad range of sizes, measuring range from tiny currents to 24kA and ease of use make them ideal solutions for a broad range of applications.
LEM offers a variety of current sensor technologies:
- Hall Effect
- Fluxgate
- Air-Core (Coreless)
Hall Effect Current Transducers
LEM Hall Effect current sensors are available in open-loop, closed-loop and Eta configurations. Open-loop Hall Effect sensors are highly cost effective, as well as being small and consuming minimal power. Closed-loop sensors offer higher accuracy and enhanced speed to enable currents with a wider range of frequencies to be measured.
Hall Effect Eta transducers are similar in construction to closed loop transducers , with the same magnetic circuit geometry, a Hall generator and secondary winding. A Hall Effect Eta transducer is a mix of open loop and current transformer technologies operating as an open loop transducer at low frequencies (up to 2…10 kHz depending on the specific transducer design), and as a current transformer at higher frequencies. Both the Hall Effect and transformer signals are electronically added to form a common output signal.
Fluxgate Current Transducers
A “standard” closed-loop Fluxgate sensor uses a secondary winding to counteract the field generated in a magnetic circuit by the primary conductor. Although similar in operation to a closed-loop Hall Effect sensor, the Fluxgate uses a saturable inductor using a small thin magnetic core to sense the airgap field, rather than a Hall Effect transducer.
Other Fluxgate transducers built on the technology to deliver specific benefits. They are:
- Low-Frequency, where the field sensing element is wrapped around the toroidal core, rather than using a gap to make more cost-effective sensors
- C-Type, built like the low-frequency Fluxgate sensor, but with a separate core to improve high frequency performance
- IT-type that uses two toroidal cores with opposing excitation coils.
Air-Core Current Transducers
The material used to create the core can limit the performance of the transducer due to characteristics such as remanence, hysteresis, non-linearity, losses and saturation. So the design of an air-core or coreless transducer is often considered.
Examples of air-core current sensors include Rogowski coil transducers.
More information:
For more information about different current transducer technologies, download Isolated Current and Voltage Transducers: Characteristics, Applications, Calculations.
To find a current transducer for your application, visit the LEM Current Transducer Selector Tool.
Voltage Transducers
LEM offers a wide range of voltage transducers (also called voltage sensors) to allow isolated measurement of voltage. The broad range of products measures voltage from 10 V to 6.4 kV, with a variety of technologies including Hall Effect,Fluxgate and insulating digital.