Search results for query: *

For those in favor of DC motors, would you still use this philosophy on >230kV, independent pole breakers?

Has anyone had good or bad luck with SEL's "Connectorized" relays? We've typically used the screw type terminals.

Here is an example 10 MW battery system you could build... http://gigaom.com/cleantech/xtreme-power-a-super-battery-for-hawaiian-wind-farms/ It may be a little pricey for a machine shop.. all you need is a $117 million dollar DOE loan.

That is the typical size of bank at that voltage. Most new bank locations have two 12 MVAR banks, each with their own breaker. The utility also has several smaller sub-transmission cap banks to support the 115kV voltage.

Hello all, I’m trying to find the inrush current a new 12 (24MVAR future) 115kv Capacitor bank. I found the formula: I(max)=1330*?(KVAR/LS) for 60hz, Where, LS is the system inductance in microhenries. Now, I know that: Xl=2?fL=377*L Or... L=Xl/(2*pi*f) So my question is, should I just...

I am curious to see how other people incorporate physical separation in primary and secondary line relays, I'm not talking about separate DC, CTs, etc. On 115kV to 230kV transmission lines, is it necessary to use different panels? If the two relays are on the same panel, is it best to put...

What is the proper way to show Control Switch contacts on DC Control schematics? Is it best to: 1) show all contacts as a simple open contact symbol, having a contact development show which contacts are closed during different switch positions, labeling next to the contact what state the...

Good point. There is a large debate for old school vs new school here, and you all have great information for me to have an understanding in the debate. Thanks again.

Would it be easier to do BF on all tripping device, (differential lockouts, primary & secondary line relays, etc) though a dedicated BF relay? Thank you bacon4life for that document.

Rafiq, So you are saying the fuse should blow just fine, except it may not be able to interrupt the current during a fault (since it is rated well below the availble fault current)?

Thank you all for your suggestions. Hopefully we can come to a conclusion on how we will apply BF for future applications.

I am fresh out of college and entered a Substation/Transmission Engineering position, where currently there is a debate on Breaker Fail philosophy. The question is: On a radial 115kv substation (designed to expand to breaker and a half scheme) is it best to: 1. Use a separate 50BF relay...