What is the meaning behind the file name automatically assigned to the extracted cards that are sent to Cigré?

How do I distinguish between service condition "during testing/maintenance" and "directly after testing/maintenance" asked in failure cards in questions 5.1 (CB), 4.1 (DS), 4.1 (IT), 5.1 (GIS)? [Question wording : Service conditions - option : "During or directly after testing/maintenance"]

Does visual  inspection by an electrical worker or craft person belong to "scheduled maintenance" in questions "Date of last/next planned maintenance"?

How can I know what revision of the survey tool I have ?

In all failure cards appears the text: "Please answer" appears in front of the dates of §3 even though the chronology is correct. Why?

What is the meaning of "incorrect operation" in the primary failure cause category?

 

Most earthing switches are only "earthing arms (with separate drives) installed on disconnectors". How shall they be calculated in the population card?

Concerning question 1.3 of IT failure card there are some doubts about what kind of sealing to select for IT of GIS. According to our experience, the classification of hermitically sealed and non-sealed has been used for freestanding type of IT with oil sealing.

If we have the failure IT in GIS, how should we select the kind of sealing for them? For example:

CT installed in the gas enclosure = Hermitically sealed?

CT installed outside of enclosure = non-sealed?

Some manufacturers specify CTs for protection and for measuring as separate units. How should this be counted?

Instrument transformer population card : when I describe a voltage transformer, what should I fill in the column entitled "current transformer arrangement" to make the red "error" label disappear?

How should a utility with no experience of internal breakdown in their equipment answer questions 3.3 and 3.6 in the GIS maintenance card?

What parts should be considered as auxiliary equipment in question §3.7 of the GIS maintenance card?

What accessories are included in question §3.14 of the GIS maintenance card? Are only those related to only monitoring to be included?

GIS Maintenance card: how should I proceed if the maintenance strategies depends on the rated voltage ?

GIS Maintenance card: is it necessary to fill in all the remaining questions of §4 if the answer to §4.1 is "no" ?

GIS Maintenance card: if I don't perform all dielectric (power frequency, LI, SI) tests at commissioning, how can I answer §2.4 and §2.5?

GIS Maintenance card: after answering “Yes” in §5.1 and “No” in §5.2 questions §5.3 to §5.6 disappear. Why?  

Answers to Frequently Asked Questions

The filename is a concatenation of the following items separated by '_':

1.   a three letter code starting with ‘P’, ‘F’ and ‘M’ for population, failure and maintenance cards and a short form of the equipment (CB for circuit-breakers, DE for disconnector and earthing switches, GI for GIS, IT for instrument transformers)

2.   the year the information is referring to

3.  the three character abbreviation of the country

4.   a date stamp that uses the day of the year, the parity of the minutes and seconds when the extraction is initiated.

The concatenation of items 2 to 4 is in cell M66 of the ‘utility info’ worksheet.

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a) If the failure was discovered after testing/maintenance, i.e. after the equipment was energized as (like) in O.K. conditions, fill the same and/or almost the same month and year as "Date of failure" into question "Date of last scheduled or corrective maintenance". That means that dates in questions No. 3.2 and 3.3. (CB), 2.2 and 2.3 (DS), 2.2 and 2.3 (IT), 3.2 and 3.3. (GIS) will be identical and/or almost identical.

b) If the failure was discovered during testing/maintenance, i.e. before the equipment was energized again (put into service), the date in "Date of last scheduled or corrective maintenance" will differ a lot (much earlier) than date in "Date of failure". It will be the date of last maintenance performed before that maintenance when failure was discovered.

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No. Simple periodical inspection of whole substation performed usually several times per year would always mean that in the years of last/next maintenance will be the same as the year of the failure.

Under Windows2000 : look into the properties of the file (right click on file icon, choose "Properties" under Excel once you've opened the file : from the menubar choose "file" and then "properties". In the new window, select the tab "summary".

This is a bug. The logic that checks the chronology will be corrected in the new version of the tool. For the time being, just ignore these "please answer" and continue filling in the questionnaire.

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In general, the primary cause of a failure is the root or first cause that initiated the failure event. Many times the root or first cause is not readily apparent at the time of failure and is only determined after thorough investigation. For example, a breaker may fail to operate due to a stuck mechanism latch.  Preliminary investigation my reveal aged lubrication as the cause.  Root or primary cause investigation may further reveal that the wrong lubrication was used and the lubrication instructions were incorrect.  The root cause of the failure would not be a failure of the lubrication but an improper application of the lubrication and a lubrication material change must be initiated.  

The selection of “incorrect operation” for the primary cause of failure is quite rare.  “Incorrect operation” describes for the situation where the operation staff or control system triggered a sequence of events that caused an equipment overload or excessive stress that resulted in an equipment failure. An example of an “incorrect operation” initiating a failure is the failure of an inductive voltage instrument transformer due to ferroresonance that was generated by operating disconnectors in an improper sequence.  “Incorrect operation” as a failure primary cause is in most cases caused by human error made during switching sequences. 

Note : The primary cause mustn’t be mixed with the “failure mode” classification category in failure cards. The failure mode describes in a general way how the failure occurred but not the specific cause.  For example, a breaker may fail to operate due to a stuck mechanism latch.  The mode of failure is “Did no open on command”, the cause of failure may be aged lubrication and the root cause may be incorrect lubrication instructions.

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It is understood that each disconnector with drive is 1 unit and also each earthing switch with drive is 1 unit. It does not matter whether an earthing switch is freestanding or built on to a disconnector (or other apparatus). In other words, any set (3 phases) of earthing arms, independently whether the set is free standing or installed at disconnector, is calculated as one earthing switch. Example: One set (3 phases) of disconnectors with one earthing arms  + one set of disconnectors with two earthing arms + one set of disconnectors without any earthing arms + one set of separate (freestanding) earthing switches represent a population of 3 disconnectors and 4 earthing switches.

Concerning question 1.3 of IT failure card there are some doubts about what kind of sealing to select for IT of GIS. According to our experience, the classification of hermitically sealed and non-sealed has been used for freestanding type of IT with oil sealing.                                                                                                                                                          

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If we have the failure IT in GIS, how should we select the kind of sealing for them? For example:

CT installed in the gas enclosure = Hermitically sealed?

CT installed outside of enclosure = non-sealed?

 Let's ask first a question what "hermetically sealed" means. "Hermetically sealed" means that there is no contact between the hermetically sealed parts (internal atmosphere) and the ambient air atmosphere. The internal atmosphere can be oil, SF6 or even dry air - important is that this internal atmosphere has got specified characteristics, must keep this characteristics and mustn't be influenced by ambient air. Keeping in mind this explanation:

CT installed inside GIS enclosure is for sure only "hermetically sealed", CT installed outside enclosure can be both "hermetically sealed" or "not hermetically sealed" based on design (see terminology above).

CTs with several cores more or less built/housed together should be counted as one unit

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Nothing. In case of a voltage transformer, just ignore the cell in the "current transformer arrangement" column and the red "error" message at the end of this line.

You do not have to experience an internal breakdown to be able to answer the question. The question asks your opinion and experience with preventing failures. That means that if a company hasn't had any internal breakdown it was because either monitoring/diagnostic showed deteriorated conditions in time (answer YES) or monitoring/diagnostic didn't show anything because was no breakdown occurring (answer NO).

All parts included in the GIS delivery that are not at high voltage.

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Generally the question concerns any accessory that is needed for GIS monitoring and diagnostics (for its HV part, operating mechanism, secondary equipment) and that has to be designed by the GIS manufacturer and delivered together with the GIS. It asks for "specialties" not for "normal, common" items.

Please fill in a maintenance card for each voltage class. In a new version of the tool there will be the possibility to select multiple voltage classes if the maintenance strategies are identical for several voltage classes

No. You can skip the questions §4.2 to §4.7 and proceed with §5.1. Also ignore the red "please answer" in the remaining part of §4.

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You can skip the questions §2.4 and/or §2.5 and proceed with §2.6. Also ignore the red "please answer next to the skipped questions.

This is a bug. Until a new version of the tool is launched use the “work-around procedure” described in the following: 

1. Read all questions §5.1 to §5.6 without performing any changes in the drop-down menus, and put your answers on a separate piece of paper. 

2. Fill in the answers of §5 in reverse order (begin typing in your answer for §5.6, then select the right answer in §5.5 and work upwards to §5.1). 

3. Depending on your answers in §5, some or all answers will be hidden from view after you've done that. However, the answers will still be accessible to the Working Group for analysis. 

You will be able to review your answers for these questions until the first “No”. The “hidden” questions will reappear if you change (in order this time) the answers for §5.1 to §5.5 to “Yes” only. This allows you to reset the answers of §5 and to restart the procedure.

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