Literatúra a softvér

The fault current is set to 80mA tosimulatethe high current generated at the intermittent earth fault. The zero voltage is set to 20V;theconfiguration ismade in13 states.The fault states and the first two memory states are set to 20ms. The memory states havetimesselected togetthetrip as close to set time 1,2s as possible. In generator configuration,set U4gen to aux voltage DC.Set “Advanced mode” in SVERKER configuration.

Monitoring částečných výbojů je zásadní pro bezpečný a spolehlivý provoz energetických zařízení, jako jsou transformátory, kabely, zapouzdřené rozvodny, generátory, motory a další elektrická zařízení. Aktivita částečných výbojů v čase může způsobit postupnou erozi izolačního materiálu, kdy náklady na odstranění následných nečekaných poruch mohou být fatální.

This is an easy solution to measure the impedance values for cables, the values are used for calculation of compensation factor in distance protection.The compensation factor is first theoretically calculated and these values can now be compared with the measured values.

The test and maintenance of electrical components on rolling stock is not an easy job to do. Some maintainers dismount some of the parts and bring them to a central location for revision and maintenance. This is a cumbersome and time consuming exercise. In many cases, the electrical parts are replaced only when they break down and are not subject to periodical testing. This of course holds a risk as some parts, e.g. circuit breakers, are crucial for safety reasons.

Transformer equipment manufacturers (OEMs) have a critical need to measure true ratio, as they must confirm proper manufacture of their transformers during construction and final assembly. Improper construction has consequences of higher cost, late delivery, and poor quality. The ability of a ratio instrument to be used for all steps involved makes it a practical valueto OEMs because only one instrument is purchased and used throughout each stage. Only the most reliable and accurate instruments make it to the factory floor. Winding stack under constructionre used: Art Mandigo Winding Service.

This application note is more than a description of how to use SVERKER 900 for testing frequency relays. It also wantsto spread the knowledge about IEC standardization in relay protection. Many engineers often associate theIEC series of protection standards IEC 60255-1xx1to relay type testing, and believe that they do not need to have competence about this series of standards. This is a misunderstanding: many of the concepts, definitions and test procedures described in thestandards are there to be used in relay technique, no matter if the role is relay manufacturer, user, or commissioning / maintenance testing engineer ([2], [3]).

When measuring very low resistance the four-wire test method has for many years been the standard method. The main advantage being that it simply and easily removes the resistance of the test leads from the measurement. However, what happens when those test leads need to be verylong?

Introducing the first low resistance ohmmeter to feature a difference meter, a device that turns changes in resistance into a moving pointer and percentage change. When testing multiple similar connections, it makes it easy to spot those small increases in resistance that eventually turn into major faults.

Safety warnings for DLRO2

Completing turns ratio tests on all transformer taps can be a cumbersome process. With One Touch OLTC from the TTRU3, anyone can configure and test all taps within a few short minutes.