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Hopefully they bring back the missing features. So far, this is way to much work move between threads.

Is there a button somewhere to read the next thread?

Tape shields typically have low current carrying capacity, so I would always expect a separate neutral to be run with tape shields. Concentric neutral can come in either full size or 1/3 size. Full size concentric neutrals are typical in single phase applications like underground residential...

The Electric motors & generators engineering would have been a better forum. However, I think most folks that read the generators forum also browse this forum. This is a bit outside the typical posts for either of these forums, so eng-tips might just not have the right audience for your...

Do you have reason to think the loads are balanced across phases? Perhaps there is twice as much load connected to B phase?

Extending the example to a rather extreme case, I suspect error would be quite large if you had a burden of 2400 Ω and current of 0.01 A.

Lots of drawbacks to using oil filled cables rather than solid dielectric at 138 kV. For shorter distances like this EPR can be an alternative to XLPE.

Transformer no-load (excitation) losses are mostly reactive power. There may be either stepdown transformer to serve the motor, or a control power transformer.

We use Alumoweld-Aluminum-Clad-Steel-Overhead-Ground-Wire for overhead shield wires.

crshears- Dielectric footware decreases the risk of death from step/touch potential, but increases the occurrence of painful shocks due to the human body forming capacitive voltage divider between the energized conductor and the ground plane. Hopefully this doesn't digress too far from the...

I dropped those unbalanced voltages into a simulation with a set of 25 MVA transforms, and it showed 46 amps of neutral current due to the circulating current. Beckwith has a good explanation of how to run a hand calc at...

Are there any load tap changing transformers or voltage regulator? Perhaps phases on different transformer taps could cause neutral current.

Wow, I would be surprised if you can find 3 manufactures with lead times that short, regardless of cost or quality.

Although many relays can be set to scroll through metering values, the font size and screen brightness often require standing within arms length of the relay in order to be able to read the screen. Separate multifunction are often readable from the far side of the control room and well outside...

I have come across a few underground components with ratings that are OK at 12.5 kV but would be inadequate at 13.8 kV. Many of the overhead clearance distances in the NESC are specified were originally based on a distance per kV plus a x foot buffer. At distribution voltage levels between...

Based on your previous request in thread https://www.eng-tips.com/viewthread.cfm?qid=517145, are you talking about utility level grid imbalance? Normally imbalances are solved by reconnecting loads/generators to a new phase. That just involves an electrician using simple hand tools like...

Thanks for the clarification crshears. I had misunderstood that the withdrawal of BAL-004 did not actually mean the end of MTEC. I am confused what changed since NERC posted the BAL-004-0 White Paper Clean suggesting to terminate MTEC. This image from the 2023_FRAA_Report_Final shows the...

Within WECC there are several frequency events per year that drop below 59.95 Hz. Dropping to 59.90 Hz happens perhaps once a year. This presentation shows a recording of WECC event that dropped to 59.85 Hz...

Historically in the eastern interconnection when a significant time error had accumulated, the grid operators temporarily adjusted target frequency to either 59.98 Hz or 60.02 Hz for a few hours to fix the time error However, this has a reliability risk because it positions the system closer to...

The SEL-651R has several options for communication aided tripping. It is not quite a differential, but it would be significantly faster than standard overcurrent relaying. SEL is also experimenting with some cutting edge schemes intended for detecting dropped conductors, perhaps those might...