450 MCM Uluminum in 2-1/2 Inch PVC??

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Jimmyboy

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Greetings! I have an underground electrical service (Single Phase, 200 Amp, 120/240) that I will be installing next week. Here's the problem. The new structure is 500 feet from the existing utility pole. My plan is to install the new 200 amp meter enclosure, 10 feet from the utility pole. I am then installing 450 MCM Aluminum, from the meter to the structure (500 feet) to minimize the voltage loss.

This is my first encounter with 450 MCM Aluminum, (so please pardon my ignorance :?).

Will it comfortably fit in 2-1/2 inch Schedule 40 PVC, and does it comply with NEC code? The utility company did not offer any suggestions, however they strongly recommended that I use the voltage drop calculator, and I did.
I do realize I will have a slight voltage drop due to the distance (about 4% at 150 amps), however, the new structure will only have (6) 8 foot fluorescent fixtures, and roughly (4) 20 amp branch circuits (for work bench receptacles).

Anyone think I will run into issues??
Any help would be greatly appreciated.
 
Jimmyboy said:
Greetings! I have an underground electrical service (Single Phase, 200 Amp, 120/240) that I will be installing next week. Here's the problem. The new structure is 500 feet from the existing utility pole. My plan is to install the new 200 amp meter enclosure, 10 feet from the utility pole. I am then installing 450 MCM Aluminum, from the meter to the structure (500 feet) to minimize the voltage loss.

This is my first encounter with 450 MCM Aluminum, (so please pardon my ignorance :?).

Will it comfortably fit in 2-1/2 inch Schedule 40 PVC, and does it comply with NEC code? The utility company did not offer any suggestions, however they strongly recommended that I use the voltage drop calculator, and I did.
I do realize I will have a slight voltage drop due to the distance (about 4% at 150 amps), however, the new structure will only have (6) 8 foot fluorescent fixtures, and roughly (4) 20 amp branch circuits (for work bench receptacles).

Anyone think I will run into issues??
Any help would be greatly appreciated.
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According to nec table C10 (A) you will be close to max fill. It can be done but you may want to consider 3 inch pipe, sleaving the 2.5 in 30 foot chunks, or pulling it thru without the 90's then sleeve the 90 ' s and last bit of pipe. Not sure what the loads are but you could also consider going with smaller conductors. Consider your absolute max load and then consider even if that happened, how long would it last?
 
what size N and G? they take up room but the N might not have to be full size.

can you get the utility to wire it to a tap that kicks the voltage up a notch?
 
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petersonra said:
I had another thought. Do you really need to run 120/240V to the structure? it appears like you only have 120V loads.
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But if he just runs 120V he will have two to four times the voltage drop and may end up worse off because of the larger conductors needed.

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GoldDigger said:
But if he just runs 120V he will have two to four times the voltage drop and may end up worse off because of the larger conductors needed.

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I wonder if these are service conductors or a feeder.

if it is a feeder he could just run 240 and an EGC and put in a transformer at the other end.

if it is service conductors he can run 240 and a N and put in a transformer at the other end.

there are all kinds of options.
 
How about putting the meter closer to the building and seeing what the utility charges to hit the meter.

Our area, we can often run the pipe and pay a per foot charge to the poco for them to run the wire the longer distance. Usually way cheaper than over-sized conductors, with the added bonus if there is a problem in the future, generally it is in the poco run, not your short run.

Additionally, the pipe size will likely only be 2" if the utility feeds the meter.
 
cpinetree said:
How about putting the meter closer to the building and seeing what the utility charges to hit the meter.

Our area, we can often run the pipe and pay a per foot charge to the poco for them to run the wire the longer distance. Usually way cheaper than over-sized conductors, with the added bonus if there is a problem in the future, generally it is in the poco run, not your short run.

Additionally, the pipe size will likely only be 2" if the utility feeds the meter.
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Since POCO is going to use the smallest conductors that meet their design rules, you may just be trading voltage drop in your wires for voltage drop in their wires. The equipment is not going to know the difference.
 
GoldDigger said:
But if he just runs 120V he will have two to four times the voltage drop and may end up worse off because of the larger conductors needed.

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According to the OP he is running power for six lights and four 20A branch circuits. I don't think he has a voltage drop issue, I think he has a voltage drop calculation issue.

I don't see any need to go larger than 250AL and that is only because he is running a 200A feeder.
 
ActionDave said:
According to the OP he is running power for six lights and four 20A branch circuits. I don't think he has a voltage drop issue, I think he has a voltage drop calculation issue.

I don't see any need to go larger than 250AL and that is only because he is running a 200A feeder.
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if it is a feeder he can install what ever size CB he wants and then size the wire accordingly.
 
You guys are great! That's why I really like this forum.

To answer a few of the replies..

@Bob,, I must run 240 because they are talking about installing an air compressor in the near future. I'm sure it won't be huge... just enough to run some air tools to work on their tractors...etc.

@Action Dave... I do realize that the likelihood of them EVER drawing 150 amps will never happen, however, the utility company suggested I use worst case scenario to cover myself.

@Petersonra.. Even though the head of engineering is a great guy to work with... they won't guarantee me anything except 120/240 (to the meter) ..and even at that.. they have a 6% window. So in the heated summer... I could actually have a slight issue. :weeping:

@Cpinetree.. Utility company requirements, is the meter can not be installed more than 200 feet away from the transformer pole. In my situation.. from the utility pole all the way up to the new structure, is all parking lot. I spent 2 hours with the utility company and the property owner, to come up with the only solution is to install the meter on a pedestal 10 feet from the pole, which is on the edge of the parking lot.

In addition.. I spoke to a contractor today, that has run into this situation in past years... He suggested that I install the meter at the 10 foot point (where it has to go)...and he said run 350 MCM Aluminum up to the structure. He said since my total load is so low ...even worst case they draw 80 amps.... I would only have a VD of 2.5% (roughly). At that point (80 amps :eek:hmy:) I would still have 230 volts. Does this sound right??


Again... Thanks for all the help, friends!
 
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