Recent content by jnunner

My guess is that you ran the short circuit module with the breaker closed and then reran it with the breaker open. Have you rerun the fault current calculation? Also, it could be that ETAP won't update the fault current with a value of zero.

If I understand you correctly this is an indoor substation facility. My apologies, I don't have any experience with that grounding that sort of installation.

I know you've said that your company won't send you out of state, but if you want to get a good understanding of grounding, you could try kinectrics, who are offering a 2 day course out of Chicago or Toronto. With the low cost of the course, I think you could justify the expense of going out of...

Poutchi, The existing grid will affect the results of the 4 point Wenner method test. The short answer is you can minimize the influence of the existing grid using the methods that cuky2000 suggested. The worst case is taking a measurement traverse parallel and close to the existing grid...

SES has published several articles on ZOI. Particularly interesting is "Zone of Influence around Electrical Installations Subjected to Ground Faults" which compares simulated methods to IEEE 367-1996 for determining ZOI. As a CDEGS user you should be able to request this document from SES.

I use the resistivity of the crushed rock when it is wet. If you refer to IEEE 80, you will find that the lower wet resistivity provides less insulation, and the station will have lower safe limits for step & touch voltages.

I have a concern with your statement: "I have been told that the whole plant is located on a bedrock(at least minimum 13m deep)." I am assuming that soil resitivity measurements weren't taken at this site. A good grounding design starts with soil resivity data, gathered from testing done on...

In section 13.3 of IEEE 80, there is a formula to determine the resisitivity of the soil based on the measured resistance. This formula is dependant on the depth of the probes. If the value of the probe depth is much less (say 1/20th) of the probe spacing, then the effect of the probe depth is...

We had the same problem when the laptop we use had to be replaced. I'd say it was your lucky day, as I was having a rather dull one... ;)

SRAM PC card work around for Windows XP Insert the SRAM card into the PCMCIA PC Card slot When the 'Hardware Wizard' appears, select 'Install from a list or specific location (advanced)' Click NEXT Select Don't search I will choose the driver to install Click NEXT Scroll through the list...