18(Houston/Sec.)25
IEC/TC18 Plenary meeting Houston 1998-10-14/16
Doc. 18 (Houston/secr)25
Report from working group 25 high voltage switchgear and controlgear assemblies
The working group has found problems to get started as neither IEC60092-302 low voltage switchgear and controlgear assemblies nor IEC298 AC metal enclosed high voltage switchgear and controlgear assemblies appeared to be available in some decent electronic format.
Further IEC298 was not organized/laydout in nowadays template for drafting standards and would not be in the near future.
This has forced me to scan both standards, reorganize it and start from scrap more or less. The first draft has been discussed in May and following subjects had to be discussed further：
- Layout of the standard
- Protection against internal faults
- Dimensions of switchboardrooms with respect to harmful excess pressure.
- Separation of cubicles
- Mainbusbar subdivision, separation essential circuits
- Combination of equipment in a cubicle
The workinggroup gas met 11 10 98 in Houston and decided the layout will be a combination of IEC298 clauses regrouped as per new layout and templates and IEC92-302 with as little references as possible. The source clauses in the committee draft will be indicated in square brackets.
Also the other above mentioned subjects have been discussed and a committee draft will be circulated end of November 1998
The formula for harmful excess pressure due to an internal are has been obtained from a study of the Trondheim University and will be addressed further.
