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Thank you Compositepro ! there will be operation mannual for those in substation.Maybe the value can be lower than that in general area. As per AS 2067 table 5.1 ,we can found the value 6.7m for 115kV ,but is it the same value for that in the substation or the general area? And what's the value...

The line above the road is 115kV . The user is state grid in southeast asia. I found that someone noted the clearance between the energized line to the car body was 1650mm. But how is this value 1650mm derived? which standards?

1. Whick guide recommend Cone Method for lightning protection ?as we know ieee 998 recmmend Rolling Sphere Method. 2. When calculating Zs, Does the parameter R0 namely the equivalent radius of the bundle refer to the metallic radius of the bundle ? Is this right that R0=18.88mm/2=9.44mm...

could anyone help me on this problem? the Minimum Clearance of the energized phases and a trolly in a substation? In other words, the Minimum clearance of the road to the energized bus in a substation? Which standards or guide tell us about this issue? As per IEEE 1427 ,we can find the phase...

what's the difference of wave impedence and surge impedence of the conductor? when in lightning protection calculation,there will be surge impedence of the conductor involved. But could anyone tell me what's the difference between wave impedence and surge impedence of the conductor?

The question is that how much is the required separation distance in air of the shield wire and the phase conductor.the distance maybe relating to the system voltage to some extent. for a 500kV system or 10kV system it can be changed.

Thanks a lot for your kind reply,Dave. But I do think the air clearance between the shield wire and the phase conductor in the substation couldn't be that of the phase conductor to the ground.Cos Direct Lightning Stroke would result in very very high voltage which could break down the air in...

Thank you Tinfoil.the reason is that if there is a thunder or lightning strike on the shield wire, and the air clearance is too short between the shield wire and the phase conductor,there would be overvoltage counter strike on the phase conductor. Thus we have to determine a distance for the...

Dear Melspuds,Thanks a lot for your kind reply! Unfortunately,I can't find any words relating to this topic in Std 998. I want to check the air clearance between the shield wire and the phase conductor!Thanks!

In a substation design, we choose shield wire for protection against lightning. How to determine the clearance for the shield wire and the phase conductor in case of lightning couter attack? Are there any IEC standards regarding to this issue? P.S. if the distance is too short ,there may be an...

it's better that the resistance and reactances are all be involved in the calculation

As a matter of fact, the content for QA is different for different tasks ,after all the engineering, design and construction work are different.moreover you can adjust based on different situation of the projects.

Normally the time for the autoclose operating sequance of CB can be different from that for the manual operation.It's recommended that u refer to ABB local service for details of such type of CB.after all the electrical arc extinguishing maybe different from type to type .

Is it right that you wonder the parameters of the 34.5kV fuses for the temporary old transformer which is 9/12/15 MVA, Delta/Wye Gnd, 26kV/4.16 kV? It's recommended not to oversize the fuse which could promote the power loss and reduce the power transformer's life ,even make the output power...

Could anyone help me for the solution about how to use Unistrut to support a vertical cable ladder along with a vertcal steel column? Pictures for the installation would be much better. Thanks in advance!

I was confusedby the frase " using 3CTs instead of 6 " . How can you get the differential current?

The SFC is to start the motor. Due to the SFC which the busbar is connected to,there will be low frequency electrical system in the busbar when the SFC takes fuction to start the motor. I wonder how to define the charcteristic of the busbar because of this low frequncy system. Just...

SFC is widely used in pumped storage power plant,but how to choose the busbar which is located in the output of SFC? Any special characteristic of the busbar?how about its working status in low frequency electrical system?Are there any standards for the isolated phase enclosed busbar used in...

odlanor ,it's so nice of you to give this help!

Thanks you. I download the pdf file. I find that the selection of the capacitor only relates to the voltage in thi file. But I find there are different values for the surge capacitor with same rated vlotage in ABB relative documents. Then how to choose the value for those with the same voltage?