Critical electrical measurement applications found within the rail transit industry require equipment that can keep up with the demands
seen. Safety, precision, speed, and ease of use, are all important factors to consider when making component selection. Depending on the application, different factors might weigh heavier than others.
Monitoring electrical parameters within equipment such as switchgear and rectifiers is often important to gauge system performance. Additionally, the detection and interruption of short-circuit events is critical to have in place and act upon, for safety purposes.
Included below are two representative questions related to transducer specifications, for applications tied to switchgear monitoring and short-circuit detection. They are followed by a downloadable chart which could be useful when comparing the Knick P42000 versus representative devices available to consider for applications such as these, and others related to electrical measurement.
|Q: “How quickly should a short circuit be interrupted in high-speed circuit breaker (HSCB) applications?”|
|A: “According to European rail standards, it should occur within 20-60 ms. This is achieved through a combination of quality protection relays and high-speed circuit breakers coupled with voltage transducers exhibiting fast response times.”|
|Q: “What level of voltage isolation, (sometimes referred to as insulation or working voltage), should be built into traction power switchgear for safety purposes?”|
|A: “Based on various rail standards, electrical protection built into equipment should represent 2x the maximum voltage expected to be measured. For 750 V and 1500 V systems, this represents isolation voltages of 1500 V and 3000 V, respectively, as well as test voltages in excess of 10 kV.”|