LILCO Ltd - lilco@stockweb.net
Lilco Ltd. has exploited developments of modern magnetic and resistive materials to produce a range of current transformers capable of faithfully reproducing current waveforms over a bandwidth which extends from a few hertz to greater than 50MHz. Whether the requirement is to measure capacitor discharge pulses of thousands of amps or milliamp currents in lf or hf electronic circuitry, it will be found that a Lilco current transformer is capable of satisfying the application.
When a transformer is used to monitor current, the measurement circuit is electrically isolated from the circuit under investigation. This is a major advantage when compared with the use of shunt resistors. The isolation proves invaluable when other measurements, such as voltage, are to be monitored simultaneously. Isolation avoids the problems of ground loops and provides protection from high-voltage conductors. The magnetic construction and screening minimises the pickup of unwanted signals and current transformers are impressively immune to noise.
Current transformers impose a negligible burden and their use has insignificant effect on the performance of circuits examined.
They are passive devices. Their ability to operate without a power source facilitates their permanent instalation in equipment and avoids distortion that could be introduced by electronics. Accuracy is typically +/-0.5% and is controlled during manufacture. The high-quality materials employed in the construction ensure long-term stability. The intrinsic accuracy of the transformer over a wide frequency spectrum is appreciated when wave-forms containing high-frequency harmonics are to be monitored.
Lilco current transformers have superior accuracy and higher frequency response than other devices which operate on the principle of magnetic coupling, such as Rogowski coils and Hall-effect devices. The advantages of electrical isolation, low insertion loss and superior high-frequency characteristics enable them to displace current-measuring shunt resistors in many applications.
The broad frequency response and wide current measurement range of the transformer makes it particularly useful in the following applications:
 | Measurement of turn-on and turn-off performance in power semiconductor switches |
| Development and servicing work in power electronics |
| Lightning simulation testing of surge arrestors |
| Capacitor pulse discharge tests |
| Motor controller and electronic variable speed drive development |
| Monitoring of laser pulse currents |
| Measuring harmonics in mains power cables and for EMC testing |
Home | Method of Use | Electrical Characteristitics | Biasing | Specifications | Technical Support