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Hi What is the role of an electrical engineer in relation to specify wood or steel poles for distribution of power in as compared to a structural engineer. I have a riser pole from a substation yard that will be taking one 750 MCM cable and then it will be a run of approx. 1 km at 13.8 KV. I...

Thanks. I wonder, why these small things could be so complicated at times. Utility normally provides: 3 Ph( SC) 1Ph (SC) and Z(+ve)where Z(-ve) will be same as z(+ve) Z(zero Sequence) This line this is coming to our installatin is certainly from a sec. of a 115 kv/69 KV transformer. AS our...

Thanks dpc. It is a feed from utility, and I dont know, if their system is resistance grounded or not. But mostof the utility substations are solidly grounded and I dont know why utilities ground them in this fashion might be a trend thing I guess. Do you think, is there any other reason for...

Thanks dpc. I will go through this pdf document and probably will help me getting a better picture of the whole switching mechanism. I have another question to add here. I got this info from utility for the primary of transformer. Base MVA-100 69 KV I(3Ph)-4000 A I(1Ph)-3183 A Pos. seq...

Thanks all for your input. In my case, the HV side of transformer has already bushing arresters. This is an industrial installation. The sec.(13.8 KV) is fed to a switchgear. Now, what I am trying to get to basically at a theoretical level is that having either a surge arrester at switchgear...

Hi, Could anybody advise me the advantages of having a surge arrester on secondary bushing of a transformer(44/13.8 KV) or the switchgear which is being fed from this. I think, the reasons could be on lines of switching voltage or lightening protection. I would appreciate a word. Thanks

Jensen, "the vertical wires may be insulated from one another" So how does this matter. I am working on a substation project and fencing might be coming shotly in my way. Is there are any literature available to get a better feel for it. Thanks

GTstartup, What is wrong about Vinyl coated fence ? Thanks

It is a good point actually, I never wondered utility information is what cycle value. I think most of the utilities use PSEE like packages for running load flow or short circuit information. and When a customer asks for a short cicuit level...what value of current they provide ? If they...

Thanks Jghrist. I was discussing this concrete foundation issue with one of the civil engineers and he said that they use a screen mesh encased in concrete to support foundation and connect it to rebars. Should I presume that in case of substation grounding, this galvanized steel screen...

Thanks rcwilson. When you used the term High resistance, that can be implied as an insulator. I agree there will be step and touch voltage but they will loose their significance as there will be no current flow. It is like doing a maintenance on a live high voltage line ? An lineman wearing...

Thanks All for your comments. Jghrist, I am using WinIgs for my simulation. A conceptual question: Earth potential profile or surface potential or ground potential, Whatever we call it: In a substation, the physical arrangement consists of 4-6 inch of crushed rock, bakcfill of soil and then...

Hi, I have a situation, where I might have to consider(As advised by Sr. guys) connecting a new substation ground grid( Grid A) to a near by existing grounding grid(Grid B). The near by existing grid has no surface installation and is connected to another substation grid( Grid C) located at a...

if we use an Motor Cicruit Protector, do you think we still might have an issue with that ? I beleive in a MCP, you can just change the settings on the dial. Other option possible could be, Change the fuse and overload as required and we are fine ? Thanks

Hi, This is my first question on Motor forum. I was wondering, can I use a 60 HP fan motor on a size 5 NEMA starter which is good between 100-200 HP motors. Actually, the client does not want to buy a new starter and wants to use same starter when he is done with 60 HP fan application, he will...

Thanks all for your suggestions. There is some thing else that came up in regards to this drive issue. I wonder, if henceforth I should beleive these sales guys or even application engineers from these Drive companies. If some thing goes wrong in the end, you cannot hold any thing against them...

Thanks all for your suggestion. In regards to Q #1, Because this whole project is on 3000 m altitude, I had to design power system for the installation. So, I am very much familair with this air density issues but it does not answer the question. Because, how people get around this sitution is...

Hi Everybody, I have this thread in two sections. This is related to a mine hoisting application and in some earlier threads I have seeked your suggestions and they were very useful. Now the project is with a company that is involved in mine hoisting applications design. We being the consulting...

Hi , Kinda old post, but this issue has surfaced again in one of my projects. LionelHutz, You mentioned using a 5160 V cap. bank on a 4160 system. What advantage do I have ? Jraef, You explained this meat plant situation and what I infered that a dedicated cap. bank for those new four speed...

Thanks All for your comments. Could you throw some light on the transient phenomena involved. When a motor starts, most of the starting current, which is six or seven times and most of this is reactive in nature and if my capacitor is connected at the same time, than the motor will suck power...