PKV/M7 instrument is resistant to frost. Results of Workshop in Neryungri

In late November, 2014 at invitation of the branch "South Yakut electrical networks" ("SYEN") of JSC "Far-Eastern Distribution Company (FEDK)" and branch "Neryungri GRES" of JSC "Far-Eastern Generation Company (FEGC)", SKB EP company has held two individual training workshops in Neryungri city (Sakha Republic (Yakutia)). The program of the individual workshop accounts the existing high-voltage equipment stock and purchased SKB EP diagnostic instruments or those of interest.

The "SYEN" "Neryungri GRES" branches operate PKV/M7 and MIKO-1 instruments for control of high-voltage circuit breakers, thus the workshop program was designed in such a way to consider all key aspects of work particularly with these instruments as well as to answer to all questions that participants are interested in: theoretically and practically.

Practical work with representatives of "SYEN" "Neryungri GRES" was performed on MKP-110, VMT-110 and VMPE high-voltage circuit breakers. Prior to test MKP-110 oil circuit breaker at sub-zero temperatures, the specialist of SKB EP company recommended workshop participants to use micromillikiloohmmeter MIKO-2.3 in thermometer mode. The point is that oil viscosity increases at negative temperatures and may affect the results of recorded characteristics of MKP-110 circuit breaker speed and time, for that reason it is necessary to control forced heating and measure oil temperature by means of MIKO-2.3 prior to perform actual tests.

Some participants of both workshops said that PKV/M7 instrument would not be able to operate at low temperature (-15˚С), notwithstanding that instrument regulated temperature range is intended for operation at -20˚С - +40˚С. The representative of SKB EP company performed the test and proved that PKV/M7 is resistant to frost and is suitable for operation at northern regions.

Notwithstanding that PKV/M7 instrument is operated by "Neryungri GRES" for more than 6 years the ability to analyze the charts was practically unused. And GRES representatives stated that it was the great assumption which could eliminate circuit breaker failure (in 2013), having prevented its failures at early stages. The instrument software (SW) allows users to analyze data charts by overlapping them. This feature provides accuracy of indicators and in case of slightest deviation of one of the chart branches it makes possible to detect immediately prospective failures of the circuit breaker. Thus, the following defects were detected on MKP-110 oil circuit breaker according to results of tests performed within the framework of training workshop and chart analysis carried out by means of PKV/M7 instrument SW:

• Jamming of the sliding rod at the beginning of travel;
• Faulty buffer;
• Partial travel of the movable contact and poor pressing force;
• Wear down of the arcing and last contact springs;

Thus, it is not recommended to conduct a control within the framework of the standard plan. It is better to conduct it more frequently as without timely and periodic control of the high-voltage circuit breakers the inceptive failures that can develop and lead to emergency situation may be missed.

"This workshop was productive and such workshops should be held more frequently as the personnel changes and periodically requires training. Within the framework of the workshop we were told about micromillikiloohmmeter MIKO-2.3. We did not know about it before as kept on using microohmmeter MIKO-1 in order to measure transfer resistances. But here we familiarized ourselves with instrument having wider current and resistance range.Mmeanwhile, it provides the possibility to measure oil temperature that is very useful for our weather conditions and circuit breaker types. Therefore we are going to purchase MIKO-2.3 in the future. During the workshop the MKP-110, VTM-110 and VMPE circuit breakers were measured at low temperatures by means of PKV/M7 instrument on substations No. 47 and No. 50. And we ensured that PKV/M7 instrument operated stably".

"SYEN" "Neryungri GRES" brunches
Electrical Substations Group Director S.Yu. Zolotukhin

"The workshop of this type was held here for the first time, but it should have been held much earlier as there were discussed matters on diagnostics taking into account design features of our equipment… We use your instruments for a long time but still there were doubts that PKV/M7 can be operated at temperatures lower than -15˚С, and during the tests we found out that it is operable. I think that such workshops shall be held as they are useful for personnel. A lot of circuit breaker failures could be avoided if the personnel had experience in performance of deep diagnostics".

"SYEN" "Neryungri GRES" brunches
Chief Specialist of Operations Department N.M. Kashkarov

The second workshop in Neryungri city held for the specialists of "Neryungri GRES" of JSC "FEGC" was mostly of an introductory nature as this entity only plans to purchase PKV/M7 instrument. The listeners appreciated the practical usability and functionality of PKV/M7, that is evidenced by eagerness to collaborate with SKB EP company in the future and equip "Neryungri GRES" with modern PKV/M7 instrument for diagnostics of high-voltage circuit breakers.

"All required information that we were interested in was obtained. We were very pleased to listen to the specialist of the SKB EP company. The use of PKB/M7 instrument for our station was clarified, for that reason we plan to purchase PKB/M7 instrument and look forward to further cooperation with SKB EP company".

"Neryungri GRES” of JSC “FEGC"
Electric equipment repairmen Yu.Yu. Yur

During the workshops all key aspects of operation of SKB EP company instruments on high-voltage equipment were discussed, but at request of event participants special attention was paid to features of measurement and detection of defects in high-voltage circuit breaker mechanisms.

Contact us if you and your company want to study the instruments practically and in details. We can help you to solve all of your problems. You can always leave a request for an individual workshop in "training" section on the company website, and our specialists will contact you.