# Very Long Run EGC Pole Lights



## Cletis (Aug 20, 2010)

Let's say you have to run out to 20 pole lights. 

It's 1,000 ft to 1st one then say 200 ft to each succeeding one. 

Let's say you run 2/0 Cu to 1st then #1Cu to 2nd then # 3 to 3rd then #4 to 4th and so on compensating for power drop and voltage drop. 

What size EGC do you need to run with that whole setup? Same, Bigger, Smaller


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## BBQ (Nov 16, 2010)

Cletis said:


> Let's say you have to run out to 20 pole lights.
> 
> It's 1,000 ft to 1st one then say 200 ft to each succeeding one.
> 
> ...


250.122(B) has your answers


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## Cletis (Aug 20, 2010)

*answer*

Thanks,but, I already know answer. Wanted to see what others think ...:whistling2:


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## BBQ (Nov 16, 2010)

Cletis said:


> Wanted to see what others think ...:whistling2:


Others wonder if you are an electrician.:whistling2:


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## Cletis (Aug 20, 2010)

*one more thing*

Let's say they are on a single pole 100 amp 277volt breaker


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## BBQ (Nov 16, 2010)

Cletis said:


> Let's say they are on a single pole 100 amp 277volt breaker


OK, 'They are on a single pole 100 amp 277 volt breaker.'

This is fun, what can we say next?


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## Jlarson (Jun 28, 2009)

BBQ said:


> what can we say next?


WTF are they smoking over in Georgia now? :laughing:


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## Cletis (Aug 20, 2010)

*game*

You all are not playing the game right. Remember, I already know answer. I wanted to see what others think that don't know. If know answer 100% then don't comment til after the wrong answers come in...:jester:


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## BuzzKill (Oct 27, 2008)

Jlarson said:


> WTF are they smoking over in Georgia now? :laughing:


he's not in my hood! :laughing:


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## Cletis (Aug 20, 2010)

*ok*

one more thing. there are more 4 current carrying conductors in conduit. 

If you all are so smart then post answer quick. If you don't, that means your don't know and really are not an electrician :jester:


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## Cletis (Aug 20, 2010)

*more..*

That's what I thought

one more thing

Breaker is 60C .....:whistling2: Waiting for answers


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## BBQ (Nov 16, 2010)

Cletis said:


> You all are not playing the game right.


I am on my time so I play by my rules and my rules say do not do the trolls bidding.:thumbsup:


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## Cletis (Aug 20, 2010)

*Bids*

Trust me. No bid. I did this job 2 yrs ago. Just seeing who knows what

Why would I be bidding on a 20k job if i'm not an electrician anyhow ?


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## BBQ (Nov 16, 2010)

Cletis said:


> Trust me. No bid.


LOL not that bidding. :no:




> 4. To order; to direct; to enjoin; to command. [1913 Webster]
> 
> That Power who bids the ocean ebb and flow. --Pope [1913 Webster]
> 
> ...


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## Jlarson (Jun 28, 2009)

BuzzKill said:


> he's not in my hood! :laughing:


:laughing:


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## Shockdoc (Mar 4, 2010)

I ran RMC so i'm using that as my EGC.Otherwise #8 cu with #6 conductors at 60 amps which is overkill.


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## BBQ (Nov 16, 2010)

Cletis said:


> That's what I thought
> 
> one more thing
> 
> Breaker is 60C .....:whistling2: Waiting for answers


Tell you what, you send a PM to someone we can trust, any of the Mods would be fine with me.

In the PM show your math and answers and if the mod posts that he got that PM with your answers I will go ahead and post my answers.:thumbsup:


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## Big John (May 23, 2010)

Shockdoc said:


> I ran RMC so i'm using that as my EGC....


 You use direct-buried RMC for an equipment ground?

-John


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## Cletis (Aug 20, 2010)

*Great*



Shockdoc said:


> I ran RMC so i'm using that as my EGC.Otherwise #8 cu with #6 conductors at 60 amps which is overkill.


Great Answer! What are you basing that on btw ? OCPD or Ungrounded conductor sizes? Did you derate ? 

Just askin


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## raider1 (Jan 22, 2007)

Cletis said:


> Let's say they are on a single pole 100 amp 277volt breaker


Then that would be a violation of 210.23(D).

Chris


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## Roger123 (Sep 23, 2007)

raider1 said:


> Then that would be a violation of 210.23(D).
> 
> Chris


 
Now that was a good catch!


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## Cletis (Aug 20, 2010)

Nice catch! They were 20 - 1,000 watt metal halide lights btw. What breaker now?


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## user4818 (Jan 15, 2009)

Cletis said:


> Nice catch! They were 20 - 1,000 watt metal halide lights btw. What breaker now?


One million amps.


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## Cletis (Aug 20, 2010)

Can you give an answer for once??? Please. Prove them all wrong


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## user4818 (Jan 15, 2009)

Cletis said:


> Can you give an answer for once??? Please. Prove them all wrong


You have your games, I have mine.


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## don_resqcapt19 (Jul 18, 2010)

Cletis said:


> Let's say you have to run out to 20 pole lights.
> 
> It's 1,000 ft to 1st one then say 200 ft to each succeeding one.
> 
> ...





Cletis said:


> Let's say they are on a single pole 100 amp 277volt breaker


You can't use a conductor smaller than #3 at any point on this circuit


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## al_smelter (Jan 25, 2011)

Constant current transformer, 5kV #8 direct burial single conductor cable. Connect in series. Just did our plant entrance road and parking lot perimeter. Just over a mile and a half.


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## user4818 (Jan 15, 2009)

al_smelter said:


> Constant current transformer, 5kV #8 direct burial single conductor cable. Connect in series. Just did our plant entrance road and parking lot perimeter. Just over a mile and a half.


That sounds like how they do runway lighting.


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## Big John (May 23, 2010)

Peter D said:


> That sounds like how they do runway lighting.


 I think it is/was? Sounds like you'd have to have all kindsa special fixtures for that. What happens when some maintenance guy removes a lamp? You get 5kV between your socket terminals? :blink:

-John


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## Shockdoc (Mar 4, 2010)

Cletis said:


> Great Answer! What are you basing that on btw ? OCPD or Ungrounded conductor sizes? Did you derate ?
> 
> Just askin


Total amperage at 150 watts per unit, 2 pole .upsizing conductors 3x for footage over 250'.


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## BBQ (Nov 16, 2010)

Big John said:


> I think it is/was? Sounds like you'd have to have all kindsa special fixtures for that. What happens when some maintenance guy removes a lamp? You get 5kV between your socket terminals? :blink:
> 
> -John


It is how they do it at airports and there are shunts that take the place of missing lamps.

I have never worked on the systems but in the past I poked around web sites trying to learn a little about it.

The FAA has some strict rules for airport lighting (go figure) and one of the requirements is that the lighting runs at the same intensity at each fixture so that becomes very hard to deal with when you have such long runs and the voltage drop that goes along with it.

There is a power supply that maintains constant current by varying the voltage in the series circuit so each lamp gets the same voltage no matter where in the circuit it is located.



http://www.cooperindustries.com/content/public/en/crouse-hinds/airport_lighting.html


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## Cletis (Aug 20, 2010)

*positive*



don_resqcapt19 said:


> You can't use a conductor smaller than #3 at any point on this circuit


you positive about that? Is this you "Final Answer" ?


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## Island Electric (May 9, 2011)

*


Cletis said:



Let's say you have to run out to 20 pole lights. 

It's 1,000 ft to 1st one then say 200 ft to each succeeding one. 

Let's say you run 2/0 Cu to 1st then #1Cu to 2nd then # 3 to 3rd then #4 to 4th and so on compensating for power drop and voltage drop. 

What size EGC do you need to run with that whole setup? Same, Bigger, Smaller

Click to expand...

*
L x D x K x I
*2 x 4800 x 12.9 x I= not enough info!:no:
divided by volts x 3%
= CM
then the fun starts :laughing:*

210.19 (A)1 , 210.19 FPN No. 4 ,250.122 (B), 250.122 , 310.16, Table 8 Conductor Properties.


Here is a example:

24 amp car charging station.(EVSE) operating at 208 volts. 268 ft. run. 
We are going to use 2% for this because car charging requires no more than a 2% VD and is considered a continuous load. I believe the 2% is in the 2011 NEC, 625.14

2 x 268 x 12.9 x 24= 165946

208 x .02= 4.16

165946 divided by 4.16= 39891 CM

go to table 8 and see CM and you get a ungrounded conductor *wire size of #4 that is actually (41740 CM)*.

back to this in a minute.

24 amps x 1.25 continuous load = 30 amps.
go to 310.16 to look up wire size for 30 amps. 75 degrees thwn. you get #10.

Now back to table 8 to look up CM for #10 wire. You get 10380 CM

Here you go almost done 41740 CM divided by 10380 and you get *4.02* this is what they mean in 250.122 (B) when they say proportionately.

Back to original overcurrent protection device which is 30 amps with original size wire of #10. 10380 CM X 4.02 you get 41728 CM.
back to table 8 to get your EGC and you get *#4 EGC.*

Well this was good practice....:whistling2: I have a test coming up.


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## nitro71 (Sep 17, 2009)

I know what your are "supposed" to run. I also know what I'm going to actually run..


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## Cletis (Aug 20, 2010)

*lot lights*

That's one of the dirty little secrets on inspections still....:whistling2:

Conductor/EGC sizing that is


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## don_resqcapt19 (Jul 18, 2010)

Cletis said:


> you positive about that? Is this you "Final Answer" ?


The smallest circuit conductor permitted by the NEC based on the information you have posted is a #3. Of course as you change the information about the circuit the answers will change.


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## RIVETER (Sep 26, 2009)

Cletis said:


> Let's say you have to run out to 20 pole lights.
> 
> It's 1,000 ft to 1st one then say 200 ft to each succeeding one.
> 
> ...


Consider what the sizing of the EGC should be. It should be a sufficient size to carry a fault current, and that fault current has to go back to the source of the voltage...not to ground.


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## kaboler (Dec 1, 2010)

I'd like to answer the question!!!!

btw do they make 13,000v MH ballasts?


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## HARRY304E (Sep 15, 2010)

kaboler said:


> btw do they make 13,000v MH ballasts?



For what???:blink::blink::blink:


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## Wireman191 (Aug 28, 2011)

HARRY304E said:


> For what???:blink::blink::blink:


 Electro shock therapy, he needs it.:jester:


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## kaboler (Dec 1, 2010)

If they made 13,000v, 1000w mh ballasts, it wouldn't be much of a problem. The answer would be 12 awg.


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## BBQ (Nov 16, 2010)

kaboler said:


> If they made 13,000v, 1000w mh ballasts, it wouldn't be much of a problem. The answer would be 12 awg.


So you are going to pull spark plug wire to each pole?


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## kaboler (Dec 1, 2010)

Sure! They pull spark plug wire to my house....


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## joethemechanic (Sep 21, 2011)

BBQ said:


> So you are going to pull spark plug wire to each pole?



I use the Packard 440 stuff


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## BBQ (Nov 16, 2010)

kaboler said:


> Sure! They pull spark plug wire to my house....


The point is .......... try to find 15KV wire in 12 AWG that you can pull in conduit.


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## al_smelter (Jan 25, 2011)

Decent info on CCT's (regulators) http://www.tpub.com/celec/5.htm . Each fixture still has it's own ballast, so a number of lamps removed or burned out has little effect to the entire run. The ballast is isolated in the cobra heads, so bulb changes are normal (though we de-energize the circuit anyway).

This is by far the easiest way to run long line power to multiple lighting. Obviously why they are used in runway lighting, as well as interstates and giant parking lots.

Sorry to hijack what has been a most amusing thread. So, back to the 277 single pole 500 MCM lighting feeds.


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## Shockdoc (Mar 4, 2010)

Big John said:


> You use direct-buried RMC for an equipment ground?
> 
> -John


I'm cheap:laughing:


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## Shockdoc (Mar 4, 2010)

Just run 4/0 sweetbriar all around. Done.


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