High accuracy transducer for current measurement of trackside applications

LEM has launched a new current transducer series, excellent for retrofitting trackside applications or decreasing the cost of new installations. Due to its robust design and standardised 4-20mA out, it can also be utilised in automation or the control of PV-plants. The transducer’s innovative primary circuit (patent pending), combined with two ASiCs to detect the magnetic field, allows precise current measurement.

The HTRS-series is offered in three current ranges (10A, 30A, 50A), with peak current measurement up to twice that of nominal. Despite the very high insulation test voltage of 6kV, the series is compact, measuring 72mm x 29mm x 26 mm. It also provides very good temperature stability, while mounting adapters enable the unit to be installed in existing applications.

The transducer complies with IRIS. With the device, users in the field of railway technology have a versatile series of sensors at their disposal, despite whether they work in the field of rail or signalling technology. The series is ideal for measuring currents in point machines, crossing gates and signalling systems. It can also be employed in industrial applications, such as process automation or DC collection in solar parks.

A split-core design provides a very high overall accuracy of 2% at +25C and high-temperature stability in the operating temperature range between -40C and +85C. The series has a measuring frequency bandwidth ( -3dB point) of 1kHz and provides a fast response time of 10μs at 90% of the rated current. The current consumption at maximum primary current is less than 50mA at a supply voltage of +12VDC or +24VDC.

Weighing just 35g, the transducer is more than 70% lighter than previous split-core current transducers for such applications. The current sensor has been designed to the latest standards for railway technology and industry, including UL and UKCE.