Thanks to both of you. This was in relation to several large static trip units. I am aware of the arc flash hazard here. As it turns out the question was put to me while I was doing an arc flash analysis, Why would you "rack in and out a live CB?" Having done AF analysis for three years...
Greetings. I have a question about the proceedure of "racking circuit breakers". I would assume that this is routine maintenance and is done to make sure electrical connections are in good physical order. However, I would like to know a little more about this procedure. The CB lit I have tells...
Hi Nightfox. Mabey this will help. Consider the natural response decay of a discharging capacitor. Now plug some realistic values in for R and C. You will have an extremely fast decay which makes the initial condition insignificant. Hope this helps.
BOb
The reason the IEEE 1584 has the 125 kVA exception is because it is hard to sustain an arc-flash at 240V or less without a certain amout of available fault current. The question is how much. IEEE uses 10,000 A bolted fault. However, we have a documents published that claim they have been able to...
