If an EPC will be performing this turnkey work for you then you should be asking the EPC what contingency plans they have in place. If I were you, I'd be more interested in the contractual agreements regarding liquidates damages if the EPC is unable to execute the work in the allotted time...
Odlanor,
Can you send a single diagram of your power plant? Typically BSDG sets are connected to a MV (4.16kV, 6.6kV, etc.) within your power plant. In my experience I have seen BSDGs synchornized accross the MV incoming breaker which is connected to the grid via a UAT-->GSU transformer--PTs...
mgtrp,
Specail CTs and relays?? Do you mind sharing the wiring schematics/settings of how these will be implemented? Just curious and want to learn about these types of protection schemes.
I worked in a utlity that is pretty far south so I haven't had the opportunity to see something like...
It seems like geomagnetic storm damage to transformer assets is not a very big deal to utlities--at least as it pertains to equipment protection schemes. These HILF(high impact low frequency) events only justify (finacially) having the necessary operations response and grid management...
This is a really interesting question. Does anybody know of a utility that actually implements GIC protection schemes like the ones in the attached .pdf? Where I work, I have never seen a customer specification for a GSU transformer requiring anything to protect against...
Hello Everyone,
I wanted to get some direction or possible opinions regarding the electrical implementation of “E-Stop” push-buttons used in process related systems (for example a pump that is performing process “X” which is being driven by a medium voltage motor fed from a MV controller). In...
I have experienced this same issue in the past. Our GSU neutral bushing CT polarity was reversed. Double check all CT wiring if possible perform all CT polarity testing and finally double checking the CT starpoint direction settings in your relay.
It's not a matter of DC vs. AC distribution. It's the generation of your power source. Do you expect to have the Data Center equipped with its own dedicated DC generation systems that would continuously feed the loads as well as the back up DC battery banks? No. This would be highly...
I've seen this application SUGGESTED in a few relay manuals. Sudden pressure trip coming in via relay BIs and then blocking this trip using through fault detection within the relay. I've never actually seen this applied and I wouldn't recommend it. Will the transformer be experiencing a high...
stevenal, is correct. I was looking for the contact transfer time.
However, I contacted Qualitrol and they said the two curves actually represent an operating region rather than the make vs. break actuating time curves.
In the end…according to Qualitrol…2 cycles is the transfer time from...
Has anyone performed any testing on a Qualitrol 900 to determine the switching time for the Form-C? In other words, the time (ms) from breaking to making. Also, would this action be a function of the fault magnitude in terms of psi/sec? Not sure of the mechanics behind this contact actuating...
These thieves sound pretty ballsy…..f.y.i some cities are beefing up scrap metal laws to prevent this sort of thing from happening.
It sounds like the only solution to this problem is your field crew’s response time to an outage--try to catch them in the act.. Maybe, look into a fault location...
Are these loose cable reels in a substation or actual energized cable (voltage? application?) and/or grounding cables?
We're going to need a lot more information than what you have provided.
Both is possible. It all depends on the hardware/software capabilities of the DCS you are planning on using. However, it would probably be more elegant to stick with a single protocol for your protection & control system--if possible.
Hard wired start/stop commands is still and will continue to be the preferred method for breaker control. My company has started experimenting with IEC 61850 commands from our plant DCS to various IEDs. We would implement start/stop motor commands via IEC61850 before ever using/considering...
