Hey all,
Had a question regarding concentric grounding terminations. We have a 138 - 25 kV delta-Yg power transformer feeding 25 kV switchgear via 3 circuits of 25 kV - 750 kcmil triplexed cable with concentric neutrals on each phase. Our standard is to have the concentric neutral tied to the...
Thanks, as additional background, the existing unit actually had a sister unit which it operated in parallel with. This unit has failed, and so we are in the process of replacing it with a new one. I do not believe that the fault current will vary much, since this project is a replacement...
Problem:
Have 1 existing 18 MVA (ONAN), 132:13.2kV (nominal), z = 8%, OLTC = 21 steps ±10% dy1 transformer. To supply the load, this transformer will have to be paralleled with a new transformer. The existing parallel scheme used is a "master-follower" arrangement. Typically, we order...
Mike,
Country = Canada...therefore 60Hz freq. This 138kV line connects two substations located in our downtown core. The substations step the voltage down to a distribution voltage (15kV and 25kV). At one substation, we have a pumping station, which maintains the pressure throughout the high...
Mike,
The high-pressure cable is 1.8km long and is at a voltage of 138 kV. Installing another cable would definitely help with maintaining the reliability of the system, but I am more concerned with the environmental impact of an oil leak. Because of its length and location, we can't just dig...
Thanks Mike,
Each conductor in the pipe is stranded and wrapped with paper and a concentric neutral. 3 such conductors exist inside the pipe. The pipe itself is then filled with oil which is the insulating medium. It also adds cooling properties. The pipe is coated with a special substance...
Hello,
Are there any technologies out there that enable one to detect a leak in buried high pressure, oil filled cable? The cable is located in an urbanized area, so a tracer-based method of locating is not feasible since there are roads, parking lots, sidewalks, etc in the way. I've heard...
Hello,
How does the Oil Industry detect leaks in underground pipelines? Is it strictly with the use of pressure gauges? If so, how is the exact location of the leak surmised in a long underground pipeline?
Thanks!
Hello,
Just wondering if anybody has heard of a standard for the manufacture of lead-acid batteries. We're in the process of creating a specification for lead-acid batteries for utility substation applications, and I would like to reference an accepted standard for the manufacture /...
