POCO Power Cable to my house

[charlie]

Re: POCO Power Cable to my house

Marc, in keeping with the Code discussions in this forum, the minimum dimensions should be given with the depths that some consultants and electric want for whatever lines they use (my opinion, of course ). With that in mind, the NESC depth for .601 kV to 50 kV cable is 30" of cover and 50.001 kV and higher is 42".

I am not sure many people would have a warm and fuzzy feeling if they knew they were standing over 138 kV that was direct buried just 42" below their feet.

 

[tom baker]

Re: POCO Power Cable to my house

In Washington State its a law you have to call locates before you dig. And with in 24" of the locate marks you are required to dig by hand.

If I have an area with a lot of utilites, I call in a vactor truck, it has a 8" dia suction pipe and we vactor away the material. Works great unless its really hard.

 

[frenchelectrican]

Re: POCO Power Cable to my house

charlie : i do agree with you about the codes for the poco conducter burail depth and yes i know how is your feeling about 138 kv lines buried 42 inch deep i know feel little spooky condersing the amout of voltage and intedeal arc flash over potionel ( strength) i work on one job site some time back we have 69 KV line buried at 5 feet deep with conducts encasted with cement and it was kinda pain in butt but have to meet nec and poco regulattions and when the line go up on riser on post we also went one step futher we put large "cement ring" around the post where the conducts come out .. i know it sound like over kill but it work really well the semi truck cant even crack it open at all..


i agree with you tom and the vactor is kinda new one to me but i heard it work super better than useing the exavctor unit with out hitting the undergound ulities lines at all


merci marc

 

[hurk27]

Re: POCO Power Cable to my house

Charlie
NIPSCO up here puts the gas and electric in the same trench! now if there is anything that could be more dangerous than having the fule and the source of ingnition in the same trench I would like to know what it is. We were installing a postlite feed and had the lot marked they of course marked no utilitys, we dug into a primary and the secoundarys and the high pressure gas line at about 1' under the ground luckly we didnt break through the gas line but the primarys blew a 6" hole in the bucket and I about fainted when I saw how close the gas line was the sparks went all the way to the house. of course the ground probley was lowered after the install of the utilitys but I didn't think they could put the gas in with the electric?

 

[charlie]

Re: POCO Power Cable to my house

Wayne, we have a lot of gas and electric utilities who want to do exactly that and, of course, do. The gas and electric are put in the same trench and at the same level. High pressure is used for transmission and is not normally close to any electric lines (this part I know). I expect the difference between high pressure and low pressure gas is the same as with us. We look at 15 kV as medium voltage and 600 volts as low voltage.

The concept (in my opinion) of placing gas lines that close to electric lines can be dangerous. The problem with my opinion is not knowing how high the pressure can be on a gas pipe before it is prohibited from sharing a trench, or how dangerous that would be. Bottom line, I am ignorant of the dangers involved.

Let us assume you cut both and the pressure wasn't really high, what would be the damage? I suspect a small explosion and a fire would result that would be a few feet high in the middle of the yard, in other words, no big deal. Again, note that I don't know and am guessing.

 

[jxofaltrds]

Re: POCO Power Cable to my house

What if it was a steel line?

I think it is a big deal.

What I have never understood is when developing a new subdivision, why is there not a standard for all the utilities? IE the water is in the first xx feet then the gas the the electric, you get the idea. Always the same no matter where you go.

My wife supervises the installation of gas lines and I work on electric... talk about sparks!

Mike P.

 

[charlie]

Re: POCO Power Cable to my house

Mike, depending on the area, all the various utilities are sort of stacked. Here the sewers go in first at 6' to 20' deep, then the water (to go under the frost line) at about 3' to 4', then the electric, telephone, and CATV at about 30" in a joint trench, then the gas at about 24". Most areas are about the same.

 

[hurk27]

Re: POCO Power Cable to my house

Charlie
This line had a 75 psi on it as this was what the utility worker told me when he was inspecting it for damage it was a 2" line and it would of cause a fireball up to 200' in the air as he put it. This could of been a very disastrous. because of the close proximity of the houses. And I problely would not be here today if I did break this line.

 

[hurk27]

Re: POCO Power Cable to my house

Of coures if the gas didn't ingite it would be even a bigger problem as we now have an explosion watting to happen.

 

[charlie]

Re: POCO Power Cable to my house

WOW! We have some gas transmission lines here and we can't dig around them at all without having one of their guys there while we work. Additionally, when we cross them, we have to install conduit encased in red concrete (color added). Normally we have to clear them by two feet from what I remember (its been a long time since I have done field work, I drive a desk now).

 

[frenchelectrican]

Re: POCO Power Cable to my house

wow that is pretty high pressure for gas line anyway i have a question but i know i did see it in nec code book say can use encasted conducts enclose with conrte ( dyed red ) but i cant find where it say that both 99 and 02 nec i look allover to see it but i am little lost or that is specal area related to uilties companines use that ???


merci marc

p.s. in france we have to enclose in cement covered conducts if the voltage are over 690 volts

 

[montecristo]

Re: POCO Power Cable to my house

DIG SAFE DIG SAFE