Special power supplies such as welding units; air conditioning systems; household appliances; as well as in renewable energy systems such as in photovoltaic string junction boxes and in solar inverters for maximum power point tracking.
The LEM HLSR series utilizes open-loop Hall-effect current sensing technology to measure AC, DC, and pulse currents with ratings of 10, 20, 32, 40, or 50 ARMS. LEM's expertise in open-loop Hall-effect technology enables these new devices to achieve a response time as low as 2.5 µs, as well as very low gain and offset drift levels within their operating temperature range of -40 to +105 °C.
The HLSR transducers provide an analog voltage output that is proportional to the current measured in the primary. In most applications, this voltage is converted to a digital value by an analog-to-digital converter (ADC). LEM has incorporated an internal reference voltage of 1.65 or 2.5 V into the HLSR on a dedicated pin for any external device, such as an ADC, or for designers to choose an external reference from 0.5 to 2.65 V. The reference voltage is just one of the features of the new
application-specific integrated circuit (ASIC) created by LEM designers for this development, which allows the HLSR series to provide typical accuracy of ±1% at +25 °C and ±3.4% at +105 °C, with a bandwidth of 100 kHz (-3 dB). LEM offers versions that operate on a single +3.3V or +5V power supply. LEM supplies all five models of the HLSR series in a single, compact, and innovative package that occupies only 387 mm² on the printed circuit board, less than many resistive shunt-based solutions.
The different versions of the package are suitable for surface mounting or push-in connections of the conductor on both the primary and signal/power connections. The low-profile package weighs only 5.5 g and is less than 12 mm high.
The reliability of the measurements is ensured by the high level of isolation between the primary and the measuring circuitry thanks to the large air gaps and creepage and clearances of 8 mm as standard and 14 mm on request, along with a comparative tracking index (CTI) of 600. HLSR transducers are CE marked in compliance with the EN 50178 standard for industrial applications and have a five-year warranty.
