Mora2 said:
is there some technical reason to recommend the change?
dpc said:
Well, I fully agree with dpc. I think I would also find some excuse to change the oil breakers.
The trend today is to move away from oil and to use either SF6 or vacuum. It seems as if vacuum is been used a little more on MV-systems than SF6. If you'll do a search on this site (
or on the net, you'll find a lot of useful info regarding the different mediums. Personally I am leaning more towards SF6, but vacuum have improved a lot over the last few years and the prices of vacuum breakers are much less than SF6 breakers.
Oil is no longer an acceptable medium for new CB's and has been discontinued for some time and is slowly being phased out of service. Of course you will still be able to continue to operate (and refurbish / maintain) existing switchgear but need to be mindful of the age and condition of any existing oil switchgear.
Disadvantages of oil
Inflammability, especially if there is any O2 near the generated gasses.
Additional maintanance is required to ensure that the oil is kept in a suitable and adequate operational state.
Additional fire and environmental hazard with possible leakage of oil out of switchgear.
Oil breakers are not manufactured on a large scale anymore by the world's leading switchgear manufacturers. This is mainly due to the major disadvantages as mentioned above, namely fire and environmental hazard, and high maintance requirements.
[red]Failure seldom stops us, it is the fear for failure that stops us - Jack Lemmon[/red]
Make the best use of Eng-Tips.com
Read the Site Policies at FAQ731-376