Recent content by vandal06

Scotty, what kind of effort would be involved in increasing the fault bracing ratings of the switchgear and MCCs?

"B" threw up lots of red flags with them being weasel-ly with the job offer. I've had very bad first hand experience with job offers as vague as the one you are getting from "B" - don't fall for it.

Do people actually specify separate 86 lockouts for each device? I've not seen it.

When you run the kA update utility it populates the TCC clipping current field with the maximum fault current that device is subjected to, even if you are not developing a TCC for that worse case fault. This is one of the features I don't like about ETAP.

Several of my coworkers are in various stages of the program and are happy with it. Myself, I have a BSEE from UIdaho and the quality of the professors (especially Law and Johnson) influenced my decision to go in to the power field. They are really great guys to work with and are always...

For a ground fault above 640A downstream of the feeders those feeders should operate first. Yes, all three poles will open for a fault even if it only involves one phase to ground, phase-to-phase, etc. Reason being is you don't want to single-phase any 3-phase loads downstream, and judging...

I'm not familiar with the fault currents available in your plant, I'm sure the engineer who produced the study (in Easypower, it looks like) ran those out. A ground fault of 700 A on the ASD40 AIR COMP would operate the breaker in the instantaneous band. It's hard to see but it's hidden behind...

Shot in the dark here, but maybe there is something for you in this SEL app guide. "AG2004-09 Minimize Distribution Outages With High-Speed Automatic Network Reconfiguration Using SEL-651R Advanced Recloser Controls" You can get it off the SEL website...

My mistake, I thought the original poster was also asking about SLG faults.

Scotty, wouldn't the 10A NGRs negate the low Z0 of the turbo-gens contributing to a SLG fault?

Have you discussed this with GE?

I can't offer much detail since I didn't have a heavy hand in it, but I do know several of my colleagues have grumbled about newer MV ABB metal-clad switchgear breakers we've used on projects, specifically problems with interfacing the trip coil monitors with protective relays. So if ABB says...

Rockman, for bullet point #1 - is the neutral of the feeder cable brought back separately or is it concentric?

I've used settings down to 10A before on a 50:5 CT with success. As mentioned you want to make sure this is above any expected loading imbalance.

I'm glad you are getting a new relay. The event reporting capabilities will be of great value if/when the next trip occurs.