# 200amp parallel feeders *need help



## backstay (Feb 3, 2011)

You need to do a load calc, then with the amp load do a voltage drop to figure the wire size. Two 250 feeds for a 200 amp panel is more wire than I have ever run.


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## syndicate (Feb 22, 2013)

Thanx, (load calc was 192amps, it's a big big house with heavy loads, and garage workshop with machinery) but all those things were already taken into account plus the new code changes for 2012 in canada (which i believe is very similar with NEC). I am mentioning 250 kcil because with all the factors involved 250 is the minimum i could do safely and without breaking the bank with copper.


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## 3xdad (Jan 25, 2011)

Why can't you have the poco run underground primary and get a ground set transformer up there by the house?


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## syndicate (Feb 22, 2013)

I chatted with the Hydro designer for this area a few days back askin about different scenarios of service. Pretty much any civil work for them to do, upgrades, yadda yadda is about $25,000 charged to us. The cheapest scenario they allowed us to do was relocate the existing property service pole and relocate it closer to the property line because hydro had some rules changed within the last few years and won't allow the same length of overhead free span distance. If it was just a service upgrade with the previous rules I definitly wouldn't have to upsize the wire so much.


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## 3xdad (Jan 25, 2011)

Forgive me for not understanding the situation. 

Hydro has a primary pole on the property line and that is 350' away from the house correct?

Or is there a 200A service equipment(meter) on the property line 350' away from the house?


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## randas (Dec 14, 2008)

Use a meter can with a disconnect. Once you have your service disco on the pole your options open up.
Use something like a T&B CO2-M, you get a meter socket, 200a disconnect, and splitter all in one can. The splitter should allow you to land two sets of 250kcmil.. 
And on the other end in the house set a tap box/splitter before the panel, and land your two sets of 250s and tap down to a single set to the panel.
Seems weird but for VD purposes you can absolutely tap down to the minimum size wire for the last few feet

With your original plan for the double lug meter socket you could get crimp on pin sleeves to land the 250s in the 4/0 lugs but without the disconnect at the meter you cant put the tap box before the panel in the house (hot splitter, every poco I've worked under its a no-no) and I'm not sure how else to legally land a pair of 250s in a resi panel. Besides the combo meter socket is probably cheaper than the crimp on sleeves. $5-600 off the top of my head


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## jefft110 (Jul 7, 2010)

Cant you just install a trough right before the meter and tap your 250's to 1/0's parallel or 4/0's single?


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## backstay (Feb 3, 2011)

syndicate said:


> Thanx, (load calc was 192amps, it's a big big house with heavy loads, and garage workshop with machinery) but all those things were already taken into account plus the new code changes for 2012 in canada (which i believe is very similar with NEC). I am mentioning 250 kcil because with all the factors involved 250 is the minimum i could do safely and without breaking the bank with copper.


You can't put 192 amp load on a 200 amp panel.


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## randas (Dec 14, 2008)

backstay said:


> You can't put 192 amp load on a 200 amp panel.


CEC- a resi service is non continuous, can load to 100%


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## syndicate (Feb 22, 2013)

Randas, thanks for your help. I was thinking about a disco then splitter but started pricing out everything in type 3R, but you answered everything in one product. Cheers for that.

3xdad: the metering equipment will be about 350' away from the house, and hydro's pole xfmr is an additional 100' away from the metering equipment. It's a house on 10 acres of land, last property at the end of a dirt road. Just one of those deals mate, what do you do. Honestly, and inspector probably won't even come to inspect it, which means I gotta take plenty of photos and sign off on it.


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## backstay (Feb 3, 2011)

randas said:


> CEC- a resi service is non continuous, can load to 100%


OP needs to go to the Canadian section to get non NEC info


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## Dennis Alwon (May 9, 2009)

backstay said:


> You can't put 192 amp load on a 200 amp panel.


Why not? If the load is not continuous then there is no reason you can't


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## Ultrafault (Dec 16, 2012)

Hey I did your voltage calc for you.If this is your friend just put in a 400 amp service it will provide for future expansion.

Minimum Gauge: 4/0 AWG one not parallel

DROP = IMPEDANCEperK_LENGTH x 2 x LENGTH/1000 x CURRENT x TEMPERATURE_CORRECTION / (Parallel Conductors)
( 6.9571 Volts = 0.062 x 2 x 350.0/1000 x 192.0 x 0.835 ) / (1)

TEMPERATURE_CORRECTION = 1 + ALPHA x ( TEMP-C - 75)
0.835 = 1 + 0.00323(copper) x (23.9 - 75)

Power Factor: 1.0
Conduit: PVC Conduit
1-way Distance: 350.0
Phase(/Wires): 1Φ2W
Source Voltage: 240.0
% Drop: 3.0
Temperature: 75.0°F
Wire: Copper
Parallel Conductors: 1
Amps: 192.0
Phase(/Wires): wire(s)/phase

Electrical calc pro andriod


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## frenchelectrican (Mar 15, 2007)

Dennis Alwon said:


> Why not? If the load is not continuous then there is no reason you can't


I have done that before with 180 amps caluated load on 200 amp service.,

Be aware this is only in resdentail appaction and it is not continuous load at all the actual load more like 55 to 70 amp the most with my figures what the most common items will be on.

Of course you may something about that but I ran that by the inspector and I stated real clear this is for resdential useage then he say ok but if this is in commercal all the bets is off right there.

Merci.
Marc


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## BBQ (Nov 16, 2010)

backstay said:


> You can't put 192 amp load on a 200 amp panel.


If you do the load calculations as per article 220 and the final result is 192 amps you can most certanly use a 200 amp panel.


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## Cow (Jan 16, 2008)

Why not use a 400 amp meterbase instead, they come with teardrop/parallel lugs?


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## Ultrafault (Dec 16, 2012)

Ok im going nuts did you do this insanity yet. Why dont you just fill the conduit with molten copper and call it a bus.


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## sparky250 (Aug 28, 2012)

You can use Microelectric CO2MSB-200. Will take up to 250MCM. Good for over head service, can order pole mounting hardware or just screw to 3/4" plywood. For panel side, use splitter box. I think my supplier quoted me $1000cad for this but I never ended up using it.


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## Toto (Jul 27, 2011)

Would polaris connectors in a gutter work to drop wire size back down at panel?


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## para19 (Feb 3, 2013)

Isn't parallel feeds of 250 Kcmil for a 200 A service absolutely over kill ?


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## Mshea (Jan 17, 2011)

What about a service room at the property line with a 240 to 600 volt step up. Pole service overhead with triplex to step down at the house. Use transformers with voltage correction taps to get it just right.
smaller wire between would likely save enough to pay for the poles and savings over the trenching costs. I might guess the place is on a well and septic field so no need to run water and sewer to the house? All services can then be overhead including tel and cable.


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## Ultrafault (Dec 16, 2012)

para19 said:


> Isn't parallel feeds of 250 Kcmil for a 200 A service absolutely over kill ?


Yes. Its so ungodly awfull it makes me cry.


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## ponyboy (Nov 18, 2012)

para19 said:


> Isn't parallel feeds of 250 Kcmil for a 200 A service absolutely over kill ?


wait people are talking about it?? i should've jumped in this thread weeks ago!! :laughing::laughing:


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## flyboy (Jun 13, 2011)

250 kcmil ACWU in conduit:

60 degree C - 215 Amperes
75 degree C - 255 Amperes
90 degree C - 265 Amperes

If I did the voltage calculation correctly he could use (2) 500 kcmil service conductors per phase. I guess he could drop a few sizes for the neutral? I'm too lazy to look it up.

This does not solve his lug size issue on the service equipment though.


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## farlsincharge (Dec 31, 2010)

Mshea said:


> What about a service room at the property line with a 240 to 600 volt step up. Pole service overhead with triplex to step down at the house. Use transformers with voltage correction taps to get it just right.
> smaller wire between would likely save enough to pay for the poles and savings over the trenching costs. I might guess the place is on a well and septic field so no need to run water and sewer to the house? All services can then be overhead including tel and cable.


300 feet is about when we start pricing transformers. I think in this case it may be cheaper. We still trench it, but the wire savings outweigh the transformers.

Doing one this year where the secondary is 250 metres long. We will be using 600 volt transformers. Currently the 100 amp service is fed this far with #1 copper without transformers.


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## flyboy (Jun 13, 2011)

Ultrafault said:


> Yes. Its so ungodly awfull it makes me cry.


He could go with one set of 250 kcmil parallel conductors (2-phase conductors) up to about 210 feet.... if I'm using the calculator right. 

Once you get past 200 feet the conductor size really goes up if you don't want to exceed the maximum voltage drop allowed.

If he has calculated almost 200 amps then he's right about running the parallel 250kcmil al conductors for 350 feet.


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## para19 (Feb 3, 2013)

flyboy said:


> He could go with one set of 250 kcmil parallel conductors (2-phase conductors) up to about 210 feet.... if I'm using the calculator right.
> 
> Once you get past 200 feet the conductor size really goes up if you don't want to exceed the maximum voltage drop allowed.
> 
> If he has calculated almost 200 amps then he's right about running the parallel 250kcmil al conductors for 350 feet.


I see. When you do the math it seems not that crazy. I quickly calculated with the CEC. parallel run of 4/0 AL (2 Cond/phase) 400' with 3% VD.


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## Ultrafault (Dec 16, 2012)

What on earth are you guys talking about 4/0 copper is perfect. Please tell me where this math is wrong or post your math becuase I am stunned. 

Voltage Drop: 6.96 Volts
2.9% of Source: 240.0 Volts

DROP = IMPEDANCEperK_LENGTH x 2 x LENGTH/1000 x CURRENT x TEMPERATURE_CORRECTION / (Parallel Conductors)
6.96 = 0.062 x 2 x 350.0/1000 x 192.0 x 0.835 / (1)

TEMPERATURE_CORRECTION = 1 + ALPHA x ( TEMP-C - 75)
0.835 = 1 + 0.00323(copper) x (23.9 - 75)

Power Factor: 1.0
Conduit: PVC Conduit
Amps: 192.0
Phase(/Wires): 1Φ2W
Source Voltage: 240.0 Volts
Temperature: 75.0°F
1-way Distance: 350.0 feet
Wire: 4/0 AWG, Copper
Parallel Conductors: 1 wire(s)/phase


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## para19 (Feb 3, 2013)

Ultrafault said:


> What on earth are you guys talking about 4/0 copper is perfect. Please tell me where this math is wrong or post your math becuase I am stunned.
> 
> Voltage Drop: 6.96 Volts
> 2.9% of Source: 240.0 Volts
> ...


 
TABLE D3 CEC
4/0 CU FROM T2 @ 75C = 230A
LETS SAY THE LOAD ON THE PANEL IS 200 A (HE SAID 180A)
200A/230A=0.87 DISTANCE CORRECTION FACTOR = 1

(15.8m) X (3%) X (240V/120V) = 94.8m 
94.8m x (3.28 ft/m) =* 311 '*


I get close to what you get when I use the CEC I get 4/0 CU (1 COND/PH) at 200 AMPS is good for 311'. But he wants to use AL, do a AL calculation with your app, I would be interested to find out.


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## flyboy (Jun 13, 2011)

Ultrafault said:


> What on earth are you guys talking about 4/0 copper is perfect. Please tell me where this math is wrong or post your math becuase I am stunned.
> 
> Voltage Drop: 6.96 Volts
> 2.9% of Source: 240.0 Volts
> ...


Your probably right, I'm too tired to do the calculation, but your using copper, we're using AL.


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## Ultrafault (Dec 16, 2012)

Ha your right how did u get copper stuck I my head. Id use 3/0 aluminum x2 then or even 1/0 copper x2 for the most cost savings


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