LxSR Hall-effect current transducer range is “technology breakthrough”, says LEM
At PCIM 2017, LEM has introduced six current transducer series, adding the LXS, LXSR, LES, LESR, LKSR, LPSR families to its portfolio. Each transducer can be mounted on printed circuit boards (PCBs) for non-intrusive and isolated measurements of DC, AC and pulsed nominal currents from 1.5 to 50A thanks to a choice of configuration options.
The closed-loop current transducers are based on LEM’s custom, proprietary, patented Hall-effect application specific integrated circuit (ASIC), allowing them to perform at the level of fluxgate transducers, claims the company.
The LxSR current transducer range has an offset drift that is over four times lower than the previous generation of closed-loop transducers based on Hall cells. The value reached is similar to those using fluxgate. Offset drift achieves a value between four to 14ppm/ degree C.
LEM’s spinning technique and specialist integrated circuits (ICs) have contributed to the improvements to be found in the new transducers. LEM says that the performance of fluxgate means that customers are provided with better control and increased system efficiency, but also at a significantly lower price point.
Advanced manufacturing techniques have also been introduced to meet the highest levels of quality and traceability.
LEM announced six families and 22 models, with various options, such as an integrated reference (VREF), footprint (three or four primary pins with different layouts), with an aperture and/or with integrated primary conductors and over-current detection output (LPSR models) on a dedicated pin to indicate that a measured current is exceeding its expected value, or to switch power off in the event of a short circuit.
LXSR, LESR, LKSR, LPSR models operate from a single 5.0V supply and provide their internal reference voltage to a VREF pin. An external voltage reference between 0.5 and 2.75V can also be applied to this pin.
This new series is compatible with the previous LEM LTS/LTSR/CAS/CASR/CKSR series; fitting in the same footprint, and integrating the primary conductor and/or with aperture for the primary conductor for those having this option. This compatability allows for the transducers to be retrofitted, with a choice of compact sizes and a variety of PCB mounting layouts, without compromising on the high insulation level provided between the primary and measurement circuits, says LEM.
The wide operating temperature range is from -40 to +85 degree C and even up to +105°C (LES & LESR & LKSR & LPSR series), making them suitable for use in industrial applications. For example, applications such as variable speed drives, servo motor drives, uninterruptible and switch-mode power supplies, battery-supply installations, power supplies (welding), air conditioning, home appliances, static converters for DC motor drives, and robotics integrate a higher number of transducers due to the high levels of control and automation.
The transducers are also well-suited to applications where low offset drift is important, such as in the AC output of solar power installations, where standards require a very low DC component in the output current.
LXS, LXSR, LES, LESR, LKSR, LPSR series current transducers are CE marked and conform to the latest industrial standards. They are also covered by LEM’s five-year warranty.