BACK

megger web.png

Testing Tactics:

Test Methods & Data Analysis of Offline PD Measurements on Power Cables

10 a.m. CT Friday, June 17

Attendees of this webinar are eligible to receive 

1 NETA CTD and either 1 PDH or 0.1 CEU

Power cable infrastructure is the backbone of power transmission and distribution systems. In many cases, these cables have been in service for 20 years or more. The influence of stress factors, such as water ingress, mechanical damage, electrical stress and imperfections created during manufacturing or installation all contribute to decrease cable life.  Evaluating and trending cable integrity over time is essential to improving the reliability of power transmission and distribution systems.  Partial discharge testing is an essential technique used for this evaluation and data collection.

 

Partial discharge is a non-destructive testing method that allows the end user to determine the overall cable health without impacting the life of a cable. PD measurements should be included as a part of a cable testing maintenance program to monitor the integrity of a cable system. The diagnostic information gained from these measurements will help to determine if further steps are necessary to repair or replace a cable before it fails while in service. This can significantly reduce the damage and lost operation time that may occur due to an outage resulting from an unexpected cable failure. 

 

This webinar will include power cable fundamentals, common failure conditions, the importance of a maintenance program, partial diagnostic methods, testing standards, and test data analysis. It will focus on the partial discharge testing practices and how applying the test results can increase cable network reliability. This will include the available wave forms, test setup, common cable connection types, pass/fail criteria and creating a report.    

Non-Destructive Nature of High Voltage Testing for Motor Insulation

 

1 p.m. CT Thursday, July 21

 

Attendees of this webinar are eligible to receive 

 either 1 PDH or 0.1 CEU

When it comes to rotating machines, the question is not “IF” the motor is going to fail but “WHEN” and trying to identify how close the motor is to that moment of failure, makes the task of regularly assessing the status of the insulation in the motor a particularly important one. This can be evaluated using different testing techniques.

 

Static tests are performed while the motor is disconnected from the system, typically during manufacturing, commissioning, maintenance, or repairs. The goal of static tests is to provide a proper picture of electrical characteristics of the machine.

 

The status of the ground wall insulation system is evaluated using high voltage DC (Direct Current) tests that include insulation resistance, polarization index, dielectric absorption ratio, step voltage, ramp, dielectric discharge, and dielectric voltage withstand (hipot). Other types of static tests include the application of high voltage AC (Alternating Current) to measure the insulation dissipation factors.

The turn-to-turn insulation, which is both the weakest spot and the place where most of the insulation failures originate in a motor, is evaluated during static testing using voltage surge tests. During surge tests, voltage pulses are injected into the machine windings to simulate the startup process, where a nonlinear voltage distribution exists across the winding.

 

The common element of all these tests is the injection of high voltage into the machine which always brings up the question of whether these tests are damaging to the machine insulation and whether they create the very problem that they are trying to assess.

 

Join us in this webinar where we will address the question of whether high voltage tests are destructive to the machine’s insulation system. We will show you that not only these tests are safe for the machine’s insulation system but also that they are the only way to properly assess the status of the insulation of the machine. We will discuss the different types of tests mentioned above with emphasis on how to perform them safely, why they do not damage the insulation of the machine, and how to evaluate the results of the tests once the tests have been performed.

Testing Tactics:

Innovations in Power Factor Testing

 

10 a.m. CT Friday, July 22

 

Attendees of this webinar are eligible to receive 

 either 1 PDH or 0.1 CEU

Testing at additional frequencies reveals what power factor testing at 10 kV and 60 Hz cannot.  In this webinar, case studies emphasize improved maintenance strategies with accurate 60 Hz temperature correction and immediate insulation evaluation with 1 Hz power factor.