200 Amp Meter Panel to 200 Amp Panel 182' away.

Reply

  #1  
Old 03-22-13, 06:44 PM
Member
Thread Starter
Join Date: Mar 2013
Location: USA
Posts: 5
200 Amp Meter Panel to 200 Amp Panel 182' away.

I need to connect a 200 amp load center at the house to the 200 amp metered panel with conductors in a conduit. Single phase. 220 volts. 4' bottom of panel to ground +2.5' underground+170' horizontal +2.5' back up + 3.0 to bottom of panel= 170+12 = 182' and gives me my estimate for minimum conduit length. My questions: 1) how much more conductor should I buy to make connections? 2) Granted I will use Schedule 40 in buried section; do I need schedule 80 for the risers? 3) I will run a ground wire in conduit, likely #8 bare copper. This leaves the main conductors sizes and insulation type. Local store has a 4/0-4/0-2/0 AL triplex UD for $2.64 a linear foot. This seams like a good deal but I am not sure the UL insulation is adequate. Others, I have discussed this with recommend going up one size to 250 mil and I was thinking all conduits would be the same size as in 4/0-4/0-4/0 AL and #8 copper bear. I also need to make sure I understand the best way to make the connections a the panel--use protective coatings?

I just picked up the 12-inch backhoe bucket from a friend and I am ready to trench and do this. The wife wants the house completed, go figure.

What say ye do-it-yourselfers.
 
Sponsored Links
  #2  
Old 03-22-13, 10:22 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: NJ - USA
Posts: 43,483
Welcome to the forums.

A couple of feet extra at both ends should be fine.
You can not run a bare ground in that pipe and it also needs to be #6 with a 200 amp service.
# 8 is good up to 100 amps.

That triplex you are quoting sounds like a twisted 3 wire cable for direct burial/no conduit underground services. It can't be put in conduit.

If I remember right..... 4/0 aluminum....like THWN-2..... is rated for 205 amps.
Based on your long distance.....it might be better going with 250mcm aluminum or 4/0 copper.

All connections made with aluminum wiring must have an anti-oxidant applied to the wire.
 
  #3  
Old 03-23-13, 05:42 AM
CasualJoe's Avatar
Member
Join Date: Jan 2010
Location: USA
Posts: 9,213
What size conduit were you planning on using? I would recommend 3", but definitely nothing smaller than 2 1/2".
 
  #4  
Old 03-23-13, 07:55 AM
Member
Thread Starter
Join Date: Mar 2013
Location: USA
Posts: 5
Conduit 200 Amp

Thanks for the feedback: Conduit.
1. I will use at least 3-inch Dia. Sch.40 but will do final sizing on final conductors. Question: are we allowed to reduce at the panel to make conduit connection?
 
  #5  
Old 03-23-13, 08:16 AM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: Twin Cities, MN
Posts: 11,982
Question: are we allowed to reduce at the panel to make conduit connection?
None. It is not practical to reduce the size of conduit unless you install a junction box.

Since you are planning on installing URD, I would suggest just direct burying it and only using PVC conduit for the risers. It will be much easier.

You need a minimum of #6 ground or #4 aluminum for 200 amps. I would recommend just getting 4/0-4/0-2/0-4 quadplex as it is all rated for direct burial.
 

Last edited by Tolyn Ironhand; 03-23-13 at 08:35 AM.
  #6  
Old 03-23-13, 08:30 AM
Member
Thread Starter
Join Date: Mar 2013
Location: USA
Posts: 5
Conductors 200 Amp Service

Thanks for the feedback:

1. Is the neutral wire called a conductor? Do all three wires (excluding ground at #6 insulated) in the 200 amp service need to be the sized the same or can the "neutral" wire be smaller?

2. The 4/0-4/0-2/0 AL Triplex UD at $2.64 per linear foot are individual conductors and are loose and not covered with a sheath. If they are twisted, they could be easily untwisted when taken off the reel. My concern was is the "UL" designation which I believe to be an insulation reference suitable for installation in a conduit?

3. I was told be the electric company that 3/0 copper would likely be sufficient. Again not sure if all wires need to be the same as in copper conductors 3/0-3/0-3/0, or 4/0-4/0-4/0, #6 insulated or Aluminum 4/0-4/0-4/0 or 250-250-250 mcm, #6 insulated Copper Ground? (noting that less voltage drop for a 4/0 copper or 250 mcm choices $$$ for copper not a big increase for AL to 20 mcm). Remembering horror stories about Al wiring is still wanting me to go with copper but other information has told be that the Al problems have been solved with better alloys.
 
  #7  
Old 03-23-13, 08:38 AM
Member
Thread Starter
Join Date: Mar 2013
Location: USA
Posts: 5
Direct Burial Option

Thanks for bringing up this option.

I was under the impression that conduit installation was the better route. In my case, I could go deeper with very little extra cost in direct burial at 3, 4 feet or deeper if necessary. I will now add the direct burial to the options.

I checked with my local shop and they have 4/0 and 2/0 and #4 AL rated for direct burial (URD?) at 4/0, 2/0, and #4 but not in a quadplex bundle. They could order or I could just bundle myself in a certain fashion. Is that advisable?
 

Last edited by Ruralist; 03-23-13 at 09:16 AM. Reason: added info.
  #8  
Old 03-23-13, 08:52 AM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: Twin Cities, MN
Posts: 11,982
A conductor is a wire that is used to carry electrical power. The neutral wire is called the "grounded conductor" because it is intentionally grounded, and carries current. This should not be confused with the "grounding conductor", which is the ground, and should never carry current except during a fault.

The neutral can be reduced in size, but I tend not to because I can not guarantee that the load will be balanced between the ungrounded conductors. (hots) The ground can be reduced per table 250.122

2) Yes, you may install URD in conduit if you choose. But you will find, even with untwisting the wires, getting them into the conduit will be a challenge even with very large conduit. Remember, you are required to have the conduit fully assembled before installing the wire. This is why I suggest direct burying it. Note: If it is direct burial, you need to use an insulated ground.

3) IMO you will be fine with 4/0 aluminum. Voltage drop will depend on the load on the feeder. If you are not pulling more than 150 amps at any time your voltage drop will still be less than 5% or 3% at 100 amps. Do you know your expected load?

As long at you install the aluminum wire correctly (Use paste, proper lugs, etc) You will be a-ok.

FYI - Minimum direct burial requirements is only 24"

?? How are you planning to install this large wire into your main panel? This needs to be connected to a breaker of some kind and AFAIKO there is no plug in 200 amp breaker. ??
 
  #9  
Old 03-23-13, 09:17 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: NJ - USA
Posts: 43,483
I stand corrected on installing UD in conduit. I knew it could be sleeved up at the ends but didn't know the entire run could be enclosed.

If you do decide to direct bury the cable ..... be careful of the rocks in the backfill. Sand would be preferred around the wire.
 
  #10  
Old 03-23-13, 12:27 PM
Member
Thread Starter
Join Date: Mar 2013
Location: USA
Posts: 5
Direct Burial versus Conduit and actual connection at panels

Thanks for the inputs:

Things I have to decide:

1) Direct Burial or Conduit installation. How I see at this time. Direct burial likely affords the easiest installation in regards to getting the wire into the panels since it allows laying the bundle and feeding the entire assembly of appurtenances prior to backfilling--free rotation in all directions. Fixed conduit requires pulling the heavy and stiff bundle, cable, or individual wires one at a time, and is, likely, not as easy in this respect. I have a way to use a pulling device such as a Come-Along or chain hoist suspended from a trackor to apply tension for pulling wire through a conduit. I have done this before with good success. I have never installed this big of a cable or wire bundle and would like to know if pulling one or two wires at a time is better than the entire set? Excluding wire cost differences, 3-inch dia. conduit will cost $250 for the horizontal run. The conduit option provides increased protection and accessibility. The house I designed and I am building could be modified to two or more stories in the future. I will likely go with conduit.

2) Connections at panel is my next issue as pointed out. I have Square-D Model SC816D200C Combined Service Entrance panel at the meter. Overhead entry at 250 kcmil to meter hub. Six copper leads from meter lugs: 2-leads go to top 50 amp breaker ports for groundwater well--water for fire is on when main to house is off. Four (4) leads from meter hub to four 100 amp breakers, two (2) breakers per 200 amp bus bar leads for exit to sub panel. That is how I see it, although, I may not have the lingo down yet. The panel label states, 6 AWG to 250 kcmil Feed Through. I think I would be connecting to the two (2) lugs provided from the bars located below 4-breakers barred together acting as the main switch; There is a third lug stemming from the Neutral "grounded conductor". I may have to add or increase the size of the ground wire lug to accept two wires?

Thanks for the advice--I will look at the panel at the house next.
 
  #11  
Old 03-23-13, 01:04 PM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: Twin Cities, MN
Posts: 11,982
The feed through lugs is exactly what you need. If needed, you can install some double lugs there for the additional wires. All wires off those lugs will need to be rated for 200 amps or more.
 
  #12  
Old 03-24-13, 07:01 AM
CasualJoe's Avatar
Member
Join Date: Jan 2010
Location: USA
Posts: 9,213
If you are content to use aluminum conductors, why are you wanting to specifically use a copper ground? If I were you, I'd use a mobile home feeder which includes the insulated aluminum ground.

Mobile Home Feeder

This can be used for other applications than just mobile homes, but is quite popular for mobile homes as they also require a 4-wire feeder, similar to your application.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes
'