Though the site may be interested in how a retired EE, also Master Electrician, designs and wires his own home. I had a ball doing it myself.

Rowdy

4000 Sq. Ft. Living area
1700 Sq. Ft. Basement
800 Sq. Ft. Garage Attached
650 Sq. Ft..Garage Detached
1200 Sq. Ft. RV Garage Detached
100 Sq. Ft. Generator House

400/2 Bifurcated Main
Panel P1 200/2 MCB
Panel P2 200/2 MCB
125/2 2
90/2 1
60/2 1
50/2 1
40/2 2
30/2 3
20/2 3
20/1 GFI 7
15/1 GFI 1
20/1 19
15/1 31
40/2 Spare 1
20/1 Spare 3
15/1 Spare 3

Generac Emergency Generator w/ATS

I like it. How big is the generator?

Roger

With all the sq ft listed (8450) assumed as living area, and assuming 4 small appliance circuits, 1 laundry, 1 dryer, 1 fridge, 1 freezer, 1 dish washer, 1 water heater, 1 microwave, 1 range, 2 heating units and 2 AC units...

My demand load calcs out to 171.1 Amps at 240V (41,067.5 VA), and I'm over calculating it, not by code minumums... Which would convince me that a single 200A service would suffice.

I usually ask customers, is your electric bill more that $1000 a month? If not, then 200A is plenty.

Not meant to nag or flame, just curious as to the over-design. Are you planning on using welders and such in your shop?

That would make all the difference!



[This message has been edited by sparky66wv (edited 11-02-2002).]

That's bigger than the whole area of some British houses!

Maybe this helps.

4000 Sq. Ft. Living area
1700 Sq. Ft. Basement
800 Sq. Ft. Garage Attached
650 Sq. Ft..Garage Detached
1200 Sq. Ft. RV Garage Detached
100 Sq. Ft. Generator House

400/2 Bifurcated Main
Panel P1 200/2 MCB
Panel P2 200/2 MCB
125/2 2 Sub-Feed to P1A, Sub-Feed to P2A
90/2 1 Emergency Heat Lower Geothermal Unit
60/2 1 Emergency Heat Upper Geothermal Unit
50/2 1 Lower Geothermal Unit
40/2 2 Wall Oven, Transfer Switch (Panel EM)
30/2 3 Upper Geothermal Unit, South H2O, Dryer
20/2 3 North H2O, Pressure Pump, Meter Power for Co-Op
20/1 GFI 7 Kitchen, Baths (Site, Garage, Basement use GFI Recpts)
15/1 GFI 1 Water Softener
20/1 19 General Use
15/1 31 Lighting, General Use
40/2 Spare 1
20/1 Spare 3
15/1 Spare 3

8KW Generac Emergency Generator w/ATS
Refrigerators, Freezer, Sump Pump, Pressure Pump, Various Ltg, Few Kitchen Recpts on Gen.

I also have 4-RG6, 4-RG59, 4-RG58, 12 pair Tel looped throughout.
Rowdy

Trust an engineer to use a 25 cent word when the nickle variety will do. Bifurcated? Have you been saving that one up?

I could make some serious money off of your designs, care to do some part time consulting?

Tom

He's been reading James Gleck's "Chaos"!
I guess "split" sounds too violent!



What would really impress me is if you had your own substation with a high voltage feed and paid the PoCo a flat rate of a few Million per year like some factories do...

How about a 4160/7200 Wye with an ampacity of say, 1000 Amps?

Then you'd really be the envy of the neighborhood!

Just pickin' on ya, rowdyrudy! All in good fun...


[This message has been edited by sparky66wv (edited 11-03-2002).]

4160/7200 Wye ?

Being an engineer myself, I find some features lacking in your design.

In a 4000 sqft house I would suppose some (most) of the 15/20amp runs are long enough to have important voltage drops.

In the houses I design, I install 50/60amp circuits from the main to 8 circuit subpanels and let these subpanels supply the 15/20amp circuits for 650 sqft.

In your 4000 sqft home I would set the main up as 6 50amp 220v breakers for subpanels at the top left, your 6 other 220v loads at the top right and then the misc garage/exterior loads at the bottom.

This makes the main panel area a bit tidier.

This is a great forum and based upon what I have read, I see conscientious contractors who desire to do things right. Over the years I became more and more disgusted with owners and developers who insisted on bare minimums for electrical installations. I actually had a developer tell me “I don’t give a damn about quality, I just want the light to come on when I flip the switch”. I declined to participate in his project. As I had the time and resources I tried to envision every possible remedy for the myriad of shortcomings that I witnessed during my active years and constructed accordingly. A lot of what I included has roots in commercial and industrial. There is a large amount of metal raceway indoors and PVC underground. Some items are things that I wanted to include in projects but owner’s budgets negated those frills. Electrical is not the only area where innovation was dominant. My residence has been toured by IBEW apprentice classes, NAHB groups, engineering classes from a nearby university, and several inspectors both during construction and following completion. Another item that may be of interest to the forum: In the rural county where I am located, there is no electrical permit required nor any building inspection except for the sewage treatment system. I have been actively pursuing the county to institute legislation to require permits and inspections. It’s difficult as the farmers don’t want an inspector telling them they cannot wire their barn with zip cord. BTW, I retired 10 years past and still assist small contractors in the area in mitigating problems.


Rowdy

George:
Your post jogged my memory. My calcs from 1993 indicated max VD on any circuit to be <2.5%. I had never checked VD physically, only by calcs. I checked the longest, most heavily loaded interior 120V circuit about an hour ago (2:00 P.M. CST). Second floor bath #2, 1500W heat-fan-light combo.
Voltage @ CB=125.2
Voltage @ heater (energized)=122.6
VD <2.1%
I have a POCO dedicated pad mount (50kva) approx 90 ft from service eq.
My recorder indicated that incoming voltage has varied from 127.1 to 123.9 over a period of 12 months.
Rowdy

Dedicated transformer and a voltage recorder? You sure are an engineer!

Aren't those figures a bit high? Sounds as if you could extend the life of your lightbulbs quite a bit by lowering the voltage...


[This message has been edited by C-H (edited 11-03-2002).]

rowdyrudy -- Check your utility's publishsed service conditions, before you call them on it, for your upper reading sounds a bit high. [Make darn sure your meter is accurate beforehand{!) or get ready for some embarrassment.]

At the meter, 126V {er, 252} is the ususal limit per ANSI standard C84.1-1995.




[This message has been edited by Bjarney (edited 11-03-2002).]

Rowdy, RX, MC, ENT, EMT????
John

Rowdy, after ribbing you, at least I should ask some serious questions:

What would the figures over time be for savings due to the over-sized conductors preventing losses due to resistance heating (I-squared times R) as compared to a "cheap" system?

The ads for copper point to turn-around times of a few years for copper Xformers versus Al, any similar savings here?

4160/7200V Wye: just a typical medium voltage system that is fed to some larger factories, and composes most of the power distribution systems in my area. I probably could've cited a better example, and I'm sure I said something to give Bjarney a chuckle! He's the real deal when it comes to medium and high voltages...

Savings? The higher the voltage at the equipment, the higher the losses. Higher voltage at your computer won't make it run any better, it'll just waste the extra voltage as heat. I find this idea of saving money by using bigger wires very strange.

Sparky,
I'm just questioning the voltage relationship. I have seen 2400/4160V and 7200/12470V but never the combo you describe. The math works so I am wondering if your utilities use this voltage?

Nick, Yep, 4160/7200 Wye is the common distribution systems here. 19.9 KV Delta for transmission. Not sure what the voltages are beyond that... Personally, I'm not trained for anything over 480V.

C-H
What I meant was, given the same load and the same source voltage, oversizing conductors (in this case, for the Service Cable, instead of 4/0 Al for a 200A Service, using say, 400 KCM Al in the 400A Service) what savings from resistance heating could one expect?

hey Sparky66,
the downloadable voltage calculator, that was linked a few posts ago, has a calculator in it that, if you plug in the cost of your local electricity, will calculate your savings for you, and let you decide if the savings are worth the money on the oversized wire.

Just used it on a little project I have going here at the 'road.

TW

Thanks Trainwire, I managed to miss that one!

Try to answer a few questions.
Tom & Bjarney- Went back and reviewed old roll charts from recorder. The 127.1 was only a spike in March 2002. The average A to N=124.8, avg B to N=124.6, avg A to B=249.3. This is data from June 2001 til June 2002. I was able to get the POCO to set xfmr tap to provide these voltages as I have the dedicated pad mount. The lowest voltages appear at around 5:00 to 6:00 P.M. and the highest at about 3:00 to 4:00 A.M. although the averages for July and August are lower than February and March in both time frames.

Scjohn- I have RX, IMC, EMT, PVC 40. A minor amount of Greenfield for connections. All wire Cu, THHN or XHHW insulation. UG PVC have all GRS 90’s with tape-wrap.

Tom- I once used the term “split” in lieu of “bifurcated” in a paper at the University of Wisconsin. My prof nailed me for “inappropriate terminology”. Although this occurred about 50 years ago, I haven’t forgotten.

I have two meters as I work with trial systems with the POCO. Two each 52 gallon and one 40 gallon H2O’s furnished by POCO at $1.00 each. Rebates from POCO for installation of geothermal units (Wouldn’t have any other system after experiencing it). A by-product of the geothermal units is hot water. They are connected to the H2O’s and only one of the 52 gal units is electrically energized. My H2O’s and geothermal units may be shut down by radio signal from the Co-Op. I am able to by-pass the shut downs but at a much higher rate. My bill to cool the 4,000 sq. ft. has averaged approximately $26.00 per month for the past 9 summers. Geo is not as efficient for heating. Winter monthly has been as high as $121.00 (Outdoor temp -16 degrees F). Average is about $65-$70. Total monthly averages in the $250.00-$325.00 range based upon wholesale power adjustments.

Hang-ups: Hate trac lighting, AL conductors, ill conceived code paragraphs, cheap devices and fixtures, poor workmanship. That’s for starters.
Rowdy

Rowdy,

I feel the same about some builders. My sister-in-law is having a house built by a large national builder. The only options available are recessed lights,ceiling fans, receptacles, additional phone or cable tv. The way these are priced makes it hard to justify. $75 to $100 per addtl receptacle, $100 per phone or TV. No mention is made if these are CAT5 or whether they are all home runs. No option for structured wiring etc.

Her house will be almost obsolete before she moves in. Whose fault is this? The customer that doesn't know what is available, the builder with no time in the schedule for any deviation from the 3 day rough-in or the electrical contractor for not pushing for what is better in the long run? Any thoughts?

Jim