Breaker cost

Status
Not open for further replies.
Tony S said:
Most are live tank now.
Click to expand...

I've seen that around the world, but not so much in the US. We use dead tank 90% of the time for both existing and new installations (see pic). But since you bring it up, why is live tank preferred over dead tank? What advantages do live tank breakers have?
 
mbrooke said:
I've seen that around the world, but not so much in the US. We use dead tank 90% of the time for both existing and new installations (see pic). But since you bring it up, why is live tank preferred over dead tank? What advantages do live tank breakers have?
Click to expand...

What medium are they using for the arc quenching?

SF6 is unpopular due to environmental issues, so air blast became the norm. That said there were complaints about noise with the early units.
 
Tony S said:
What medium are they using for the arc quenching?

SF6 is unpopular due to environmental issues, so air blast became the norm. That said there were complaints about noise with the early units.
Click to expand...

SF6, still common in the US if I am correct. My understanding is that vacuum only works at lower voltages.
 
zog said:
OEM, design, ratings, features, locations, etc... but figure somewhere in the $250-$350k range if you are just curious. And they still typically use SF6, just less gas than older styles.
Click to expand...

How much does interrupting capability add to the breaker, ie 20ka, 40ka 63ka? Also what do you mean by OEM (custom)?
 
Ingenieur said:
I represent that insinuation :D

live tanks are cheaper, about the only reason I can see
although they require external CT's which offset some of the savings
Click to expand...

How much cheaper? Ive seen the external CTs on those and they take up space. Not sure of the advantage, but if external CTs are less prone to saturation I guess it could be an advantage (not sure if thats true however)
 
mbrooke said:
SF6, still common in the US if I am correct. My understanding is that vacuum only works at lower voltages.
Click to expand...

ten years ago, SF6 was what all the new stuff being installed around where i was at was using.... but the
environmental issues were rearing their ugly head at that time, to the extent that LADWP had bought some
enormous amount of SF6, to cover their needs for 50 or 60 years of maintenance on all their SF6 gear....

i don't know if there is any agent that could be substituted for SF6, and i'm thinking opening or closing a
SF6 switch that wasn't fully charged, would not be a good experience.
 
mbrooke said:
How much does interrupting capability add to the breaker, ie 20ka, 40ka 63ka? Also what do you mean by OEM (custom)?
Click to expand...

I'm not sure what the adders are for that type breaker but in the MV world doubling the int rating can be up to a 50% adder. By OEM I mean manufacturer.
 
I have it on good authority that you are somewhere around $95K for the 115KV and $270K for the 345kV. And as an added bonus even though you didn't ask, $150K for 230KV.

These are for 63kA.
 
kingpb said:
I have it on good authority that you are somewhere around $95K for the 115KV and $270K for the 345kV. And as an added bonus even though you didn't ask, $150K for 230KV.

These are for 63kA.
Click to expand...

Thanks, this is the info I needed :) Am I correct that the price of these has gone down over the years?
 
Fulthrotl said:
ten years ago, SF6 was what all the new stuff being installed around where i was at was using.... but the
environmental issues were rearing their ugly head at that time, to the extent that LADWP had bought some
enormous amount of SF6, to cover their needs for 50 or 60 years of maintenance on all their SF6 gear....

i don't know if there is any agent that could be substituted for SF6, and i'm thinking opening or closing a
SF6 switch that wasn't fully charged, would not be a good experience.
Click to expand...


Don't these breakers have a lockout that prevents opening on a leak? I hope at least an alarm.

As for the environmental aspect, its all lies imo. Much like the R12. Its said that the military was the biggest contributor from their air force, not people dumping refrigerators. But to cover themselves consumer took the hit.
 
Status
Not open for further replies.
Top