AVO New Zealand

Intelligent DTS Solutions for Load Maximisation and Hot Spot Detection

Batteries are used to ensure that critical electrical equipment is always on. There are so many places where batteries are used – it is nearly impossible to list them all.

Nothing is quite so common or abundantly available throughout the world as the earth’s soil. We are more apt to think of earth as something to be tilled for planting or to be excavated for a building foundation. Yet, it also has an electrical property -- conductivity (or low resistance) -- that is put to practical use every day in industrial plants and utilities.

Why a 10 kV Insulation Tester?

What's in the name...?

For over 100 years, Megger has been a premier provider of test equipment and measuring instruments for electrical power applications. The Megger trademark was first registered in May 1903 and is closely guarded by the company. Although Megger is best known for its world-famous range of insulation testers, the company provides a full service solution to meet all electrical test and measurement needs. Megger products provide testing solutions for the most critical maintenance areas, including cable fault location, protective relay and circuit breaker testing, and power quality testing. With such a diverse product offering, Megger is the single source for electrical test and measuring instruments.

Abstract:

Measuring a transformer's winding (DC) resistance from one external terminal to another can reveal a great deal of information about the transformer. In addition to the obvious faulted winding (i.e., an open winding), more subtle problems can be detected. The DC current, in addition to flowing through the winding, must also flow through the off-load ratio adjusting switch (De-Energized Tap Changer or DETC) and the on-load ratio adjusting switch (Load Tap Changer or LTC), as well as numerous welded and mechanical connections. Hence, the integrity of all these components can be verified.

Authors note: Specific aspects of safety are addressed herein; however comprehensive procedures are not detailed. It is assumed the operator has sufficient knowledge of electrical theory and safe working practices to use the test instrument in a safe and responsible manner.

A Practical Technique FOR Battery Condition Assessment and Capacity Monitoring.

ABSTRACT:

The management of the condition assessment of standby lead acid battery systems using impedance methods is now a highly regarded and mature technology delivering an accepted compliment to load discharge methods. Offering the significant attributes of being a non-invasive diagnostic method implemented at modest per-cell costs to in-service battery systems, impedance testing may be applied both to absolute or trended ( CBM ) condition assessment philosophies. Given the often sudden nature of battery failure mechanisms, the success of failure prediction is proportional to sampling intervals. Studies have expanded the scope of impedance technology to the determination of deterioration in battery capacity.

Often just viewed as a form of ‘insurance’, an appropriate on-line monitor can not only provide a timely detection of main tank issues but also provide, arguably, an even more signifi cant contribution in the subsequent management of the event with the transformer remaining energised throughout.