ground rods

[reppy007]

............Here we usually use 1 ground rod on our 12kv dist. circuits.............transformer poles get 1 ground rod and plain inline poles we butt bond them............on our 34.5 system we use 2 ground-rods on every pole...........same with urd........12 kv 1 grd. rod.......34.5 2 grd.rods.................now when I was in southern Flordia,we only worked urd..........if Im not mistaken they wanted 8 grd rods on there urd.......we had to (ohm) them and place a tag near the ground rod........any replies on rods?..wondering if Flordia is the only area where they want 8.

[lewy]

On transformer poles we need 1 ground rod 18" from the pole meggerd to at least 25 ohms & #4 cu run up the pole, for risers it is the same except 1/0 cu. For all U.G. we need 4 ground rods 1 at each corner again meggered to 25 ohms & grounded with 2/0 cu & if there are bullards they also have to be bonded to the 2/0. On our 44kv load break switches we need 3 ground rods again with 1/0 cu run up the pole.

[reppy007]

On transformer poles we need 1 ground rod 18" from the pole meggerd to at least 25 ohms & #4 cu run up the pole, for risers it is the same except 1/0 cu. For all U.G. we need 4 ground rods at the corners again meggered to 25 ohms & grounded with 2/0 cu & if there are bullards they also have to be bonded to the 2/0. On our 44kv load break switches we need 3 ground rods again with 1/0 cu run up the pole.

lewy,are you saying that you guy put 4 ground rods on all 4 corners of the urd pot,and Im interested in where you are located..........what type of earth,rocky,sandy,gumbo,ect

[lewy]

We have all different kinds of soil except obviously we don't put transformers in swamps or mud bogs. I edited my original post.

[rob8210]

A couple of utilities here have changed there standards to allow ground plates to be used instead of rods. Really handy in rocky ground or in the city with congested underground utilities.

[Electriceel]

We use 5/8"X10' ground rods, #6 cu. for wire. All transformer pole mount or pad mount get 1 ground rod, all urd riser poles 1 ground rod, all arrestor poles 1 ground rod. All rods must test 25 ohms or less if not keep adding rods 8' from the existing one until it test properly, if conditions will not allow moving away from the pole or equipment then add coupling and more rods as needed.
All other poles except for corner structures will get a butt plate.
We are lucky to have good soil conditions and moisture.

[reppy007]

We use 5/8"X10' ground rods, #6 cu. for wire. All transformer pole mount or pad mount get 1 ground rod, all urd riser poles 1 ground rod, all arrestor poles 1 ground rod. All rods must test 25 ohms or less if not keep adding rods 8' from the existing one until it test properly, if conditions will not allow moving away from the pole or equipment then add coupling and more rods as needed.
All other poles except for corner structures will get a butt plate.
We are lucky to have good soil conditions and moisture.

Here we have never ohmed them........I know in Flordia they wanted 8 on the urd..........but ive never see 8 put down there...........Im still amazed by the soil conditions in S Flordia.....lots of sand and lots of rocks,boulders ect.By the way we did ohm them there .

[lewy]

We use 5/8"X10' ground rods, #6 cu. for wire. All transformer pole mount or pad mount get 1 ground rod, all urd riser poles 1 ground rod, all arrestor poles 1 ground rod. All rods must test 25 ohms or less if not keep adding rods 8' from the existing one until it test properly, if conditions will not allow moving away from the pole or equipment then add coupling and more rods as needed.
All other poles except for corner structures will get a butt plate.
We are lucky to have good soil conditions and moisture.

We also have to add ground rods if we don't get 25 ohms, as far as #6 I didn't think anybody used #6 anymore.

[reppy007]

We also have to add ground rods if we don't get 25 ohms, as far as #6 I didn't think anybody used #6 anymore.

Not to change the subject..........but Ive noticed that Texas New Mexico uses #6 copper solid for there high sides............Poot might know about that one since Entergy owns TNM power,,,,,we use # 4 stranded copper,,,,,,,,,easy to tell which lines belong to the other utilities even if there are two lines on each side of the road......theres more ways of telling the difference.........just the small little things mostly.

[BigClive]

I wonder how much the nature of the soil affects the life expectancy of the ground rods. Do you guys ever get involved in test son the rods to ensure they still present a low enough resistance or if they're even still there?