# Search results

1. ### Power transformer 60 hz to be tested on 50 hz

The two power transformer 69/22.9kV and 230/69kV are both rated 60/80/100MVA designed for 60 Hz operation. However it will be tested on test facility were the available supply is only 50 Hz. During short circuit test at the LV side the 60/80/100MVA rating will be tested for the lowest tap...
2. ### Reliability of substation configuration

hi!. anyone here who have an idea on how to assess the reliability of a ring bus system over an open loop/ radial system? the ring bus is composed of three load bus connected together. thank you
3. ### Closing of an open ring

hi guys, just want to ask, an open loop has three points A,B, C and each point serving a load. there is only one source (a subtransmission 69kV line from a substation), connected at point A. The loop is open at line segment AC (the circuit breaker at point C, connecting the segment AC is...
4. ### A number raise to it self infinitely

hi I have encountered this... . . X X X X = 3 I tried...
5. ### Free Fall

I if a body is thrown vertically upward (from ground), and it reaches back to ground in 10 seconds.. then the initial velocity can be calculated by Vf = Vo + gt.. where the final velocity Vf is equal to zero and the maximun height is given by s = Vot + 1/2g(t^2).. Is these correct?
6. ### Game theory

Hi, In a n-person game theory.. I have encountered these terms, superadditivity and imputation, however i do not understand much their definition. Anyone have a simple explanation to this terms? Somebody here knows where can I find a dictionary of mathematical expressions/equations in...
7. ### Underground cable

Hello guys, If form example I am given the sequence impedance of a cable ( positive, negative, zero) Will I use all of these impedances to calculate the voltage drop of the cable? or only the positive impedance? Anyone here knows where can I find table of xlpe cable (various sizes) for...