Topic '30 amps at 100 volts, really?' in forum 'Home Improvement' - dslreports.com

Re: The renovation continues ... today new 400 amp service!

Sun, 09 Dec 2012 15:34:04 EDT

whizkid3 posted :

We're on a 15kW transformer by ourselves. Service for house is 200A. Seems he told me they figure it a bit differently than you did as 15kW / 120V = 125A, and that is *per leg*...Now, I may be wrong on that

Yes, its wrong. 15kVA / 240V = 62.5A. Total. Or per leg. Makes no difference, there is no other way to do the math.

This could be exceeded when necessary, the transformer can be overloaded at a reduction of its life. 15kVA works fine for most homes - on average. That is why utilities often put up to 4 on one 25kVA transformer, which can basically only provide 100A total at rated load.

The OP's 400A service? Note the transformer its fed off of. 50kVA at best, and its shared. It puts out 200A - shared - at full rated load. But a 400A service certainly makes for a nice thread, more than most of us could post if we were trying to impress people with our service.

Re: The renovation continues ... today new 400 amp service!

Sun, 09 Dec 2012 15:06:59 EDT

Jack_in_VA posted : All of that is the legal rates but the real bottom line is the kWh used and the total cost with taxes and fees.

i.e. 121.79 / 1171 = $0.10.4/kWh

* That's why I have no interest in the overpriced LED ugly bulbs. I don't consider spending a bunch of money when I'm not spending that much on my electricity.

What is a Meter Charge? Also do you not have taxes and fees on your bill?

Re: The renovation continues ... today new 400 amp service!

Sun, 09 Dec 2012 11:01:15 EDT

tschmidt posted :

said by dplantz:

Rates should be close all over NE.

Interesting I did not realize that. Always thought of PSNH as "my electric utility" but in fact they are just part of a larger operation.

Here is a link to rates for Public Service of New Hampshire, the largest utility in the state. Residential rate is 14.88 cents per KWH plus a $11.96 per month meter charge. There are slightly lower rates for water and space heating.

»www.psnh.com/RatesTariffs/Home/R···tes.aspx

quote:
Rate R, Residential Service
Available to customers living in individual residences and apartments.

Customer Charge $11.96 Per Month
KWH Distribution Charge 3.905 Cents per KWH
KWH Transmission Charge 1.480 Cents per KWH
KWH Stranded Cost Recovery Charge 1.999 Cents per KWH
System Benefits Charge 0.330 Cents per KWH
Electricity Consumption Tax 0.055 Cents per KWH
Energy Charge 7.11 Cents per KWH

/tom

Re: The renovation continues ... today new 400 amp service!

Sun, 09 Dec 2012 05:39:45 EDT

dplantz posted : Rates should be close all over NE. NSTAR and North East Utilities merged in April. Most of NE now gets its power from the different operating companies of NE Utilties

Re: The renovation continues ... today new 400 amp service!

Sat, 08 Dec 2012 18:11:53 EDT

scooper posted : From my TED5000 - I can state that the very highest peakload I've ever seen was 25KVA on my house with 200 Amp service. The vast majority of the time, we sit at about 2KW, with some of the heavier electric users peaking it up - running the electric dryer frequently spikes to 12 KW, but that is also running the electric tank water heater recovering.

So I believe the power companies know what they're doing on their sizing of transformers for residential use.

Re: The renovation continues ... today new 400 amp service!

Sat, 08 Dec 2012 16:25:35 EDT

sk1939 posted :

said by kherr:

said by leibold:

Shouldn't it get cheaper if you buy in bulk ? ;)

Needless to say, they will have there own sub station ....

Doesn't surprise me considering HQ has it's own power generating station.

Re: The renovation continues ... today new 400 amp service!

Fri, 07 Dec 2012 15:48:37 EDT

tschmidt posted :

said by DKS:

[And full of PCB's...

Unlikely, but not impossible.

The transformer was installed in 1980 when we first moved onto the property. This was around the time of the big PCB scare. I was assured the transformer did not contain PCB. Utilities were going through a big replacement phase at the time so I have no reason to doubt the accuracy of that statement.

In the US manufacture of PCBs was banned in 1980. According the the EPA PCB use in transformers ended in 1977.

»www.epa.gov/reg3wcmd/ts_pcbs.htm

But your post prompted me to double check so I submitted a request to our utility.

/tom

Re: The renovation continues ... today new 400 amp service!

Fri, 07 Dec 2012 15:05:29 EDT

DKS posted :

said by kilovolt:

I think the scarier part is what pandora's monthly electric bill looks like. Ouch.

Indeed. Our hydro rates are so complex I can't even give a comparison. We have three segment Time of Use, delivery charges, debt retirement charges, temperature compensation, discounts and more. And Smart Meters.
--
Need-based health care not greed-based health care.

Re: The renovation continues ... today new 400 amp service!

Fri, 07 Dec 2012 14:49:23 EDT

DKS posted :

said by tschmidt:

Well that was 30+ years, a direct lightning strike, and two kids ago and the transformer is still going strong. It will probably still be there after I'm in the ground.

And full of PCB's...
--
Need-based health care not greed-based health care.

Re: The renovation continues ... today new 400 amp service!

Fri, 07 Dec 2012 14:31:11 EDT

pandora posted :

said by kilovolt:

I think the scarier part is what pandora's monthly electric bill looks like. Ouch.

I guess we all choose what we want to spend our money on...I prefer to spend it on skiing in Colorado or snorkeling in Hawaii :)

THAT is an excellent point. We do not take expensive vacations, most of our time and cash is invested in home, including entertainment.

Some prefer to travel, after the TSA, and as I grew older, home became my preferred vacation spot. I'm happier here than in any hotel. Got an 8 person hot tub, 3.5 bathrooms, 3 of them with Jacuzzi's. Lots of high tech toys to play with, and a number of pets.

I'm happiest at home with my family, they so far seem to feel similarly.
--
"If you put the federal government in charge of the Sahara Desert, in 5 years there'd be a shortage of sand." - Milton Friedman"

Re: The renovation continues ... today new 400 amp service!

Fri, 07 Dec 2012 14:20:04 EDT

kilovolt posted : I think the scarier part is what pandora's monthly electric bill looks like. Ouch.

I guess we all choose what we want to spend our money on...I prefer to spend it on skiing in Colorado or snorkeling in Hawaii :)

Re: The renovation continues ... today new 400 amp service!

Fri, 07 Dec 2012 07:48:31 EDT

pike posted :

said by pandora:

Tomorrow the first of 2 new 4 ton 18 SEER Goodman heat pumps is going to go live.

Would anyone mind if I snapped some shots and started a new thread about that?

No sir, I wouldn't mind at all. Looking forward to reading all the nitpicks from the armchair tradesmen. :p

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 20:19:55 EDT

kherr posted :

said by leibold:

Shouldn't it get cheaper if you buy in bulk ? ;)

The more you use, the bigger their capacity has to be. Whether they buy more off the grid or build larger generating capacity.

There was an article here quite some time ago where the NSA was building a data center (spy center) in CO where they will us $45M a year just for electric. I forgot how many of 100,000s of square feet it is going to be. Needless to say, they will have there own sub station ....

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 19:29:19 EDT

mattmag posted :

said by tschmidt:

Being the good engineer that I am felt obligated to point out that 200A x 240V is 48 KW. The supervisor smiled knowingly and said that was true but transformer has tremendous overload capacity.

I'm trying to recall exactly what the POCO guy said about the installation here. We're on a 15kW transformer by ourselves. Service for house is 200A. Seems he told me they figure it a bit differently than you did as 15kW / 120V = 125A, and that is *per leg*, so we would essentially have excess capacity with the current configuration. This of course assumes perfect load balancing.

Now, I may be wrong on that, its been awhile since that conversation came up. Just throwing it out for those who know more than me to cuss and discuss... ;)

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 19:21:35 EDT

Anonymous_ posted :

said by pandora:

said by Anonymous_:

growing pot? That would be only reason to need 400 amp service

No, sorry, no cannabis here. Though it does demonstrate a certain mindset. The only reason you can imagine for 400 amp service is to grow pot??

Unless your running some industrial lighting equipment 400amp service is not need.

Most houses here that are 3k sq ft only use 150amp or 200amp service

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 16:49:59 EDT

Jack_in_VA posted :

said by tschmidt:

said by leibold:

Utility companies are well aware that they can far exceed that rating at the expense of a shorter lifespan for the transformer.

Yup - I can attest to that from first hand experience.

When we built our house installed a 200A service plus 30A separately metered service for hot water. Except for kitchen stove appliances are electric. Even space heating is electric to backup wood stove.

We are 600 feet off the road so have our own pole pig. Power company installed a 10 KW transformer. Being the good engineer that I am felt obligated to point out that 200A x 240V is 48 KW. The supervisor smiled knowingly and said that was true but transformer has tremendous overload capacity. If we were able to overload it they would be happy to replace it.

Well that was 30+ years, a direct lightning strike, and two kids ago and the transformer is still going strong. It will probably still be there after I'm in the ground.

/tom

That's interesting since my transformer that feeds 4 homes started out at 15 kva, changed to 25 kva, then 50 kva and now 75 kva all without any problems I'm aware of. I'm sure my 300 amp upgrade didn't trigger it since the original drop wire from when the house was 60 amp was installed.

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 16:29:07 EDT

Speedy Petey posted : 400A service, 320A continuous.
The service entrance conductors can be sized according to 320A.

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 16:26:08 EDT

TheMG posted : Strange as it may seem, it's cheaper for the utility to deal with the occasional overloaded transformer (and replace the failed transformers with a larger one), than to preemptively upgrade transformers "just in case" the load might be too much.

The average power consumption of most homes is well below their service capacity.

Also it is unlikely that all the homes will have peak consumption occurring at the same exact moment. Heating, A/C, and HWH will cycle at different times and people will be running their electric ranges and clothes dryers at slightly different times than other people.

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 16:05:56 EDT

pandora posted :

said by Anonymous_:

growing pot? That would be only reason to need 400 amp service

No, sorry, no cannabis here. Though it does demonstrate a certain mindset. The only reason you can imagine for 400 amp service is to grow pot??
--
"If you put the federal government in charge of the Sahara Desert, in 5 years there'd be a shortage of sand." - Milton Friedman"

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 16:03:36 EDT

pandora posted : Here are some generator and propane tank pictures (with associated propane plumbing). The generator is not yet wired, but the propane is connected to it. It will be live within 2 weeks if all goes well. Without a battery it can't start (battery won't be installed until we are ready to go live with the unit).

My propane tank description seems redacted (after the post went up) the tank is 41" in circumference, 16' long and sits on a concrete pad 5' wide by 18' long.

The generator pad is oversized, and has underground cable to fit up to a 35 KW generator. We asked the propane folks to size the pipe to the generator to handle up to a 35 KW generator. The electric cable will also be sized for up to 35 KW when installed.
--
"If you put the federal government in charge of the Sahara Desert, in 5 years there'd be a shortage of sand." - Milton Friedman"

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 15:48:07 EDT

Anonymous_ posted : growing pot? That would be only reason to need 400 amp service

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 15:30:10 EDT

pandora posted :

said by leibold:

Shouldn't it get cheaper if you buy in bulk ? ;)

I defer to my current signature. :)
--
"If you put the federal government in charge of the Sahara Desert, in 5 years there'd be a shortage of sand." - Milton Friedman"

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 14:34:17 EDT

leibold posted :

said by pandora:

Shouldn't the limit vary by home size and number of people residing in it?

It kind of does here. The utility sets a baseline amount that is based in part on the type of home, whether gas or electricity is used for hot water and heating as well as the climate zone it is located in (determining the number of heating or cooling days). That calculated baseline amount is less (50-60% in summer, 60-70% in winter) then what a typical home would consume as "an incentive to conserve energy" meaning that nearly everybody pays more then tier 1 rates (up to 100% of baseline). In total there are 5 tiers with pricing going up significantly after tier 2 (101% to 130% of baseline).
From personal experience it is no problem at all to get into tier 5 (over 300% of baseline).

Shouldn't it get cheaper if you buy in bulk ? ;)
--
Got some spare cpu cycles ? Join Team Helix or Team Starfire!

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 14:13:44 EDT

Draiman posted :

said by pandora:

said by Draiman:

It's not a limit just an escalator to make people pay more for what they deem 'excessive' usage. I'm sure if Massachusetts can get away with it the other states won't be far behind. :(

I think it should be as well. Why should a 2 bedroom condo and a 4 bedroom house be held to the same standard after all. I guess they figure if you can use more then 1,000 Kwh then you can afford the extra 3 cents a Kwh too. :(
--
IF YOU FIND ANY MISTAKES IN MY WORK...Please consider that they are there for a purpose. I try to please everyone and there is always someone looking for mistakes!

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 14:08:41 EDT

pandora posted :

said by Draiman:

It's not a limit just an escalator to make people pay more for what they deem 'excessive' usage. I'm sure if Massachusetts can get away with it the other states won't be far behind. :(

My electric bill runs anywhere from 2,500 to 3,000 Kwh per month, depending on season and activity in the home. That's before we increase the size of our home.

Shouldn't the limit vary by home size and number of people residing in it?
--
"If you put the federal government in charge of the Sahara Desert, in 5 years there'd be a shortage of sand." - Milton Friedman"

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 14:06:38 EDT

hitachi369 posted : MI, or at least my energy provider, has a bump at 600 Kwh.

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 14:02:24 EDT

Draiman posted :

said by pandora:

said by Draiman:

It breaks down to about 8.5 cents a Kwh for delivery and another 8.5 cents per Kwh for supplier for a total cost of 17 cents per Kwh fixed no matter what here. Then they have a surcharge they add if you exceed 1,000 Kwh a month. That raises the rate to about 20 cents per Kwh for all Kwh's over 1,000.

I'd be in trouble with a 1,000 Kwh limit. Fortunately that doesn't exist in Connecticut (yet).

It's not a limit just an escalator to make people pay more for what they deem 'excessive' usage. I'm sure if Massachusetts can get away with it the other states won't be far behind. :(
--
IF YOU FIND ANY MISTAKES IN MY WORK...Please consider that they are there for a purpose. I try to please everyone and there is always someone looking for mistakes!

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 13:51:26 EDT

pandora posted : Tomorrow the first of 2 new 4 ton 18 SEER Goodman heat pumps is going to go live.

Would anyone mind if I snapped some shots and started a new thread about that?
--
"If you put the federal government in charge of the Sahara Desert, in 5 years there'd be a shortage of sand." - Milton Friedman"

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 13:41:56 EDT

pandora posted :

said by Draiman:

I'd be in trouble with a 1,000 Kwh limit. Fortunately that doesn't exist in Connecticut (yet).
--
"If you put the federal government in charge of the Sahara Desert, in 5 years there'd be a shortage of sand." - Milton Friedman"

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 13:18:15 EDT

tschmidt posted :

said by leibold:

Utility companies are well aware that they can far exceed that rating at the expense of a shorter lifespan for the transformer.

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 12:51:37 EDT

leibold posted :

said by cdru:

Even 400 amps doesn't fit a 75 kVA transformer. 240 volts * 400 amps = 96 kVA. It would be 125% overloaded at 400 amps alone, not to mention the other 5 homes.

Technically correct, but not relevant. The 75 kVA rating is the load limit in order to maintain the manufacturer specified service life of the transformer.
Utility companies are well aware that they can far exceed that rating at the expense of a shorter lifespan for the transformer. Given how many pole mounted transformers around here show clear signs of overheating (and how often some of them pop) it appears that our utility company prefers the more frequent replacement to proper sizing of the transformers.
--
Got some spare cpu cycles ? Join Team Helix or Team Starfire!

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 11:57:46 EDT

nunya posted : That just confirms what I said. A single phase 75 KW transformer can supply *roughly* 320A @ 100% load.
The utility knows that you'll never draw close to that. The chances of everybody turning everything on at the same time and blowing the transformer or the fuse are slim. If it does happen, they deal with it then.
--
If someone refers to herself / himself as a "guru", they probably aren't.

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 11:50:47 EDT

John Galt posted : $0.0690 per kW here in Oregon for the first 12,000 kWh, then it drops to $0.0460 for all kWh past that.

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 11:00:31 EDT

cdru posted :

said by pandora:

The wire is 350 kcmil Alcan XLPE 90C, whatever that means.

350 kcmil means that the wire has a cross sectional area of 350,000 circular mils. A circular mil is an area of a circle 1 mil in diameter. It's an easy way to measure large wires without having to worry about pi. kcmil can also be abbreviated as MCM (M = thousand CM = circular mil) and is usually found for wire gauges larger than 4/0 or 0000 and AWG is used for smaller wires. Take the square root of the kcmils to get the diameter in mils (thousandths of an inch). So √350000 = 591.6 mils = approximately .592 inches in diameter.

Alcan is the manufacture of the wire.

XLPE means Cross-linked polyethelyene plastic insulation. If you're having plumbing done, you may be using the same type of plastic there where it's known as PEX.

90C is the temperature rating on the wire. This go towards how much current a given wire or cable is allowed to carry safely. Common values are 60C, 75C, and 90C. The lower the number, the less current. It also comes into play when you need to derate a cable because of where it's located or how it is ran.

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 10:59:04 EDT

Draiman posted : It breaks down to about 8.5 cents a Kwh for delivery and another 8.5 cents per Kwh for supplier for a total cost of 17 cents per Kwh fixed no matter what here. Then they have a surcharge they add if you exceed 1,000 Kwh a month. That raises the rate to about 20 cents per Kwh for all Kwh's over 1,000.

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 10:54:13 EDT

telco_mtl posted : us in quebec its around 5 cents for the normal user and dual energy users like myself its abit over 4 cents normally and 17 cents during peak (colder than -15 celcius)

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 10:38:34 EDT

pandora posted :

said by telco_mtl:

wow, we are spoiled in quebec, 17 cents is our peak rate when you are on a dual rate meter!

Just one rate. Regardless of time of day.
--
"If you put the federal government in charge of the Sahara Desert, in 5 years there'd be a shortage of sand." - Milton Friedman"

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 10:37:10 EDT

cdru posted :

said by Jack_in_VA:

The transformer is 75 KW and feeds 6 homes. When built, all homes in the neighborhood had 75 or 100 amp service. Most now have 200 amp.

If all the other 5 crank up their usage to 200 amp that's 1000 amp which is 600 above what you say the POCO says they can supply.

Something about this setup doesn't make sense

Even 400 amps doesn't fit a 75 kVA transformer. 240 volts * 400 amps = 96 kVA. It would be 125% overloaded at 400 amps alone, not to mention the other 5 homes. And if Pandora's home is needing all 400, it's likely the other homes are also needing a considerable amount of power. That is, unless Pandora is running the grow lights operation supplying the other 5 homes. ;)

I think that guaranteed 400 amps of continuous service is shared among all the users of the transformers, meaning Pandora's house is likely never to have 400 amps available just to him.

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 10:34:56 EDT

fifty nine posted :

said by Draiman:

said by pandora:

said by PhoenixDown:

Pandora -- what are your electric rates?

The bill is complex, some costs are fixed, transmission is separate from generation. However, it's about 17 cents per KWh.

It's nice to see the Northeast is consistent on one thing. It's about 17 cents per Kwh here in the Boston area as well.

I pay $0.1215588/kwh all taxes included in my part of New Jersey. This is because we're on a co-op. On PSE&G when I lived elsewhere in NJ it was about 17 cents per kWh.

Our ETS rate (offpeak, for ETS heating only) is about half the regular rate.

Our co-op opted out of the electric utility competition so we pay just one charge for generation and transmission.

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 10:21:50 EDT

telco_mtl posted :

said by Draiman:

said by pandora:

said by PhoenixDown:

Pandora -- what are your electric rates?

The bill is complex, some costs are fixed, transmission is separate from generation. However, it's about 17 cents per KWh.

It's nice to see the Northeast is consistent on one thing. It's about 17 cents per Kwh here in the Boston area as well.

wow, we are spoiled in quebec, 17 cents is our peak rate when you are on a dual rate meter!

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 10:21:35 EDT

pandora posted :

said by Jack_in_VA:

If all the other 5 crank up their usage to 200 amp that's 1000 amp which is 600 above what you say the POCO says they can supply.

Something about this setup doesn't make sense

How utilities manage and calculate electric loads is beyond my understanding (at this time). It's interesting, but the entire project has been interesting, I've learned a lot.
--
"If you put the federal government in charge of the Sahara Desert, in 5 years there'd be a shortage of sand." - Milton Friedman"

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 10:15:24 EDT

Draiman posted :

said by pandora:

said by PhoenixDown:

Pandora -- what are your electric rates?

The bill is complex, some costs are fixed, transmission is separate from generation. However, it's about 17 cents per KWh.

It's nice to see the Northeast is consistent on one thing. It's about 17 cents per Kwh here in the Boston area as well.
--
IF YOU FIND ANY MISTAKES IN MY WORK...Please consider that they are there for a purpose. I try to please everyone and there is always someone looking for mistakes!

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 09:53:50 EDT

Jack_in_VA posted :

The transformer is 75 KW and feeds 6 homes. When built, all homes in the neighborhood had 75 or 100 amp service. Most now have 200 amp.

If all the other 5 crank up their usage to 200 amp that's 1000 amp which is 600 above what you say the POCO says they can supply.

Something about this setup doesn't make sense

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 09:13:21 EDT

pandora posted :

said by nunya:

There's nothing to get hyped up about.
The OP has what everybody incorrectly refers to as a 400A service. It looks fine. They did a nice job (I wouldn't have used SEU on a nice new install like that).

It's really a 320A service, and TBQFH he'll never use it. That transformer on the pole looks to be a 50 KVA, or at the most a 75 KVA. Add to that it is shared with other homes. There *really* isn't 320A even available to the OP.

The utility appears to have provided the service drop. The utility is subject to the NESC, not the NEC. They can pretty much put whatever they feel like in there. Remember, utility work is usually done under engineering supervision. They know that drop will never *really* even see 275A. I doubt it ever sees 200A.

Service size ≠ what's actually available from the utility.

I spoke with the utility today, their belief is the system as installed can maintain 320 amp continuous service. Loads of up to 400 amps may be sustained for long periods (according to the regional installation supervisor). He indicated if at any time, there was a failure to supply 400 amp by the cable or transformer, excluding emergency periods where there are blackouts or brownouts, the electric company is required by law to remediate the service to provide the required load (up to 400 amps sustained).

He indicated the design for all residential 400 amp service assumes no more than 320 amps drawn continuously (he said this is required by state regulation as the minimum the utility must provide).

The wire is 350 kcmil Alcan XLPE 90C, whatever that means. The transformer is 75 KW and feeds 6 homes. When built, all homes in the neighborhood had 75 or 100 amp service. Most now have 200 amp. Street voltage is 8,000 volts to the "main feed" (sometimes he used the word primary apparently interchangeably). Output read with no load to our meter was 246 volts according to the supervisor. I am not at all an expert on these things. He indicated the load was buried approximately 3' underground, with a tracer wire. My electrician had a spare conduit built, in the event there is ever a failure (as the conduit will be paved over by a long driveway).

I don't know if this helps the discussion any, but it occurred to me to ask the people who installed the stuff.

He indicated the street was not scheduled for any upgrade in the near or intermediate future, but that some poles may be replaced, and mine was on the list for an intermediate future replacement. So the pole in the pictures may be a slight concern to the company.

The supervisor indicated while the shunt is installed, they must assume the average use of all homes using the same transformer. He indicated this would save me money, as my use is more than 50% above average.
--
"If you put the federal government in charge of the Sahara Desert, in 5 years there'd be a shortage of sand." - Milton Friedman"

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 09:02:07 EDT

pandora posted :

said by PhoenixDown:

Pandora -- what are your electric rates?

The bill is complex, some costs are fixed, transmission is separate from generation. However, it's about 17 cents per KWh.
--
"If you put the federal government in charge of the Sahara Desert, in 5 years there'd be a shortage of sand." - Milton Friedman"

Re: The renovation continues ... today new 400 amp service!

Thu, 06 Dec 2012 08:54:45 EDT

cdru posted :

said by nunya:

It's because of the split service. Have you seen the price of the $400A transfer switch?

No I didn't know the price of a 400 amp compared to two 200 amp. A real quick check I found a Generac 200 amp for $600 and Generac 400 amp for $1829. Slightly more than 3x the price, but you save some of the costs by not having twice the work to do. Plus a simpler setup. After factoring in everything, and considering this doesn't seem to be a super low end job, I just would have thought a single ATS would have been the way to go.

Re: The renovation continues ... today new 400 amp service!

Wed, 05 Dec 2012 20:31:43 EDT

PhoenixDown posted : Pandora -- what are your electric rates?

Re: The renovation continues ... today new 400 amp service!

Wed, 05 Dec 2012 19:48:00 EDT

pandora posted :

said by nunya:

It's because of the split service. Have you seen the price of the $400A transfer switch?

It probably would have been better to have two panels: essential circuits and non-essential circuits. Especially since they are right next to each other. Then he would have only needed one ATS.

The concrete pad and propane feed from the tank can support up to a 30-35 KW unit. If in the future, 20 KW is insufficient, swapping out a 20 for a 30 or 35 is a heck of a lot easier than rewiring, pouring new concrete and running new propane lines.
--
"If you put the federal government in charge of the Sahara Desert, in 5 years there'd be a shortage of sand." - Milton Friedman"

Re: The renovation continues ... today new 400 amp service!

Wed, 05 Dec 2012 19:45:44 EDT

pandora posted :

said by fifty nine:

You get back 30% of that on your taxes, which is about 18 grand. I would have done geothermal if I had the opportunity.

When I ran the numbers, my total cost would be $60,000.

Each family has it's own unique situation.
--
"If you put the federal government in charge of the Sahara Desert, in 5 years there'd be a shortage of sand." - Milton Friedman"

Re: The renovation continues ... today new 400 amp service!

Wed, 05 Dec 2012 17:38:23 EDT

nunya posted : It's because of the split service. Have you seen the price of the $400A transfer switch?

It probably would have been better to have two panels: essential circuits and non-essential circuits. Especially since they are right next to each other. Then he would have only needed one ATS.
--
If someone refers to herself / himself as a "guru", they probably aren't.