Voltage transducers for railway applications

Test & Measurement

31 October 2012 Test & Measurement

LEM introduces the DVL series of voltage transducers for insulated nominal voltage measurements in traction applications. This family of devices spans the range from 50 - 2000 V_RMS and incorporates LEM’s proven and patented insulating technology.

Despite achieving very high levels of isolation with a safety insulation voltage of 8,5 kV, the transducer is compact, measuring only 137,8 x 63 x 64,3 mm. It is fully compatible with previous generations of transducers in terms of functions, performance and footprint and offers high levels of accuracy and temperature stability.

LEM developed the DVL to be fully compliant with the International Railway Industry Standards (IRIS), providing engineers in the railway industry, who are working with both rolling stock and substations, with a versatile new transducer that is equally applicable to measuring network voltages, or the main converter DC link onboard trains.

The feature set of the voltage transducer also makes it suitable for a broad range of low- to medium-voltage measurements in industrial markets. It measures voltages by a direct connection on its primary side, transfers the data across an internal isolation barrier and outputs a current from its secondary side that is proportional to the measured voltage.

It delivers overall accuracy of ±0,4 % at +25°C with high temperature stability. The technology used provides very high levels of immunity to external magnetic fields and electromagnetic disturbances.

The DVL’s measurement frequency bandwidth (-3 dB point) is 14 kHz and it consumes only 20 to 25 mA when supplied with ±24 V d.c. (power supply range from ±13,5 to ±26,4 V), a power saving of 30% relative to its predecessors. Two current output ranges are possible: ±50 mA or the standard industrial current-loop range of 4 to 20 mA.

Other key features include a high level of partial discharge extinction voltage, and compliance to a range of internationally-recognised safety standards in addition to its adherence to IRIS specifications. It also exhibits a fast response time and excellent noise immunity. A range of connection configurations, on both the primary and secondary side, increases flexibility for the user.

Designed by LEM in accordance with the latest standards applicable for traction, the DVL utilises materials that comply with all relevant fire and smoke requirements that are mandatory in railway applications. It is CE marked and is supplied with a five-year warranty.

Share this article:

Categories

Test & Measurement

Voltage transducers for railway applications

Further reading:

Publications by Technews