Power electronics is essential to driving and controlling energy in modern Transportation systems. New requirements are continuously emerging in the railway industry, such as the demand for energy measurement, track objects monitoring and a need to constantly improve maintenance infrastructures. LEM manufactures a complete range of accurate, reliable and galvanically-isolated Traction transducers for the measurement of current from 0.1A to 20,000A and voltage from 10V to 6,400V provides control and protection signals on-board as well as for trackside applications.

Key Features

Traction Transducers with Isolated current and voltage measurement with instantaneous current or voltage output. Non contact or with integrated bus bar, or clip-on current measu rement from 0.1 A to 20 000 A. High voltage measurement from 10 V to 6,400 V. High modularity offered in the various designs for a high level of mounting flexibility. Large options available for the possible secondary connections inspired by the railway market need. Traction Transducers with high precision measurement and performance with Accuracy from 0.2% to 2.7% and short response time from few ns to several μs.

For Current Measurement Application

Technology	Type	Measuring Range	Bandwidth	Typical Accuracy @ 25°C	Linearity	Response time
Hall effect	Open Loop	0-20000 A	0-25 kHz	±1%	±0.5%	< 3-7 µS
	Closed Loop	0-15000 A	0-200 kHz	±0.5%	±0.1%	< 1 µS
Flux gate	C- type	0-150 A	0-250/500 kHz	±0.1%	±0.05%	0.3-0.4 µS
	IT-type	0-25000 A	0-100 kHz	2 ppm	1 ppm	0.3 µS
Rogowski	Prime	0-400 A	10-6 kHz	±1%	±0.5%	500 mS

For Voltage Measurement Application

Technology	Type	Measuring Range	Bandwidth	Typical Accuracy @ 25°C	Linearity	Response time
Hall effect	Closed Loop	0-9500 V	Several kHz	±1%	±1%	10...100 µS
Flux gate	C- type	0-7000 V	0-400/700 kHz	±0.2%	±0.05%	0.6 µS
Isolation Amplifier	AV-type	0-3000 V	0-11 kHz	±0.7%	±0.1%	30 µS
	DV-type	0-6000 V	0-12 kHz	±0.3%	±0.1%	60 µS

Applications of LEM make Traction Transducers

• Traction Transducers used in Main converter for Metro rail, Mono Rail and Trolleys
• Track objects monitoring
• Sub-stations
• Inverters, converters, rectifiers
• Traction Transducers used in Auxiliary power units
• Circuit breaker, for transformers, DC link
• Control and safety systems
• Traction Transducers used in Energy metering
• Traction Transducers used in Rolling stock heavy traction, diesel electric
• Traction Transducers used in propulsion systems for Mining trucks

Energy measurement for railway on-board applications

• EM4T Energy Meter for Traction. Certified for all European networks. It is an independent accounting certified measuring system for single phase energy metering designed for on-board applications.

LEM transducers are CE marked in recognition of their electromagnetic compatibility and their compliance to EMC standards. Their reference standard is EN 50155 for the electrical performance and environmental constraints as well as EN 50124-1 for creepage and clearance distances design versus the required insulation levels.

Global systems for propulsion of the mining trucks are quite similar to the ones used for diesel-electric railway locomotives. Inverter control is the key for the suiting trucks propulsion. Current and voltage transducers are accountable for the right control.