Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Electrical

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 03-15-2013, 10:05 PM   #1
Member
 
Join Date: Jan 2012
Posts: 210
Share |
Default

residental 3-phase


Called the electrical company about upgrading my service to 200 ampres. The operator on the phone asked if I wanted 3 phase or single phase. I told her single phase, and she said that 3 phase was available where I was at. I thought it sounded far-fetched, but I looked out the window, and yep, there's three high-side wires up on the pole! Most likely for the school across the street.

Now, my ultimate question is are there any appliances that I can get for the home that will run on 3-phase? HVAC equipment is supposed to be much more efficient. How much savings would I get by running a 3-phase heat pump over a single phase? I am looking at upgrading that this summer. Howabout any other appliances?

av-geek is offline   Reply With Quote
Old 03-15-2013, 10:27 PM   #2
Idiot Emeritus
 
Join Date: Mar 2008
Location: Fernley, Nevada (near Reno)
Posts: 1,559
Default

residental 3-phase


I have 120/208 3 at my house. Have had it for 14 years.

These days, there's not much difference in efficiency of a single phase A/C unit vs. 3. They are however, much more reliable. Other stuff, like well pumps, etc. are about 5 - 10% more efficient 3. And if you have any type of shop equipment in the garage, used 3 stuff is usually cheaper to buy. New stuff, not so much.

The panel will be a bit more expensive, but a 150 amp 3 service has more power available than a 200 amp single phase one.

240 volt stuff, like dryers and ranges will work fine on 208, but with less heat. They will last much longer though.

If the service is 240 delta, it has a high leg. This phase is 208 to neutral, and is useless for anything other than 3 loads and 240 loads that don't use the neutral (like a water heater). The other two phases are the same as a single phase system.

If it were me, I'd get the 3 service. But I'm also a professional electrician who understands 3 systems, plus I have a bunch of 3 shop equipment.

Rob

micromind is offline   Reply With Quote
Old 03-15-2013, 11:00 PM   #3
" Euro " electrician
 
frenchelectrican's Avatar
 
Join Date: Apr 2006
Location: WI & France { in France for now }
Posts: 5,369
Default

residental 3-phase


I have three phase as well one in Wisconsin and also in France as well.

In Wisconsin typically the resdential will get either 208Y120 or 240D120 ( this part is no longer can get it for new customers )

But one instering part with my three phase service is that I can get 480Y277 due I do have commercal property next to it so it was a no brainer to get that voltage so I end up just have one service drop that it ( the house get 208Y120 thru the transfomer to feed the house only )

However over here in France the typical voltage I get on three phase is 415Y240 volts which it is pretty common over here and with larger services it automatique have to use three phase once you get over 160 amp service size or larger. ( the smaller service can have a choice of single phase or three phase and the single phase is 240 volt line to netural )

Merci,
Marc
__________________
The answer will be based on NEC ( National Electrical code ) or CEC ( Cananda Electrical code ) or ECF ( Electrique Code France )
frenchelectrican is offline   Reply With Quote
Old 03-16-2013, 08:03 AM   #4
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 6,839
Default

residental 3-phase


With the three primary (high side) lines at the top of the utility pole you have 3 phase power on the street but you still need a 3 phase transformer or transformer array on the pole to give you 3 phase (usually 120/208 wye) at your house.

The 3 phase transformer(s) may already be there to serve the school but if not, you may have to pay extra to have them installed. Inquire about the costs before making your final selection.
__________________
Stop wasting time re-adjusting the pattern. Have several lawn sprinklers, one for each pattern.
AllanJ is offline   Reply With Quote
Old 03-16-2013, 08:04 AM   #5
E2 Electrician
 
stickboy1375's Avatar
 
Join Date: Apr 2012
Location: Litchfield, CT
Posts: 4,633
Default

residental 3-phase


What purpose would 3 phase serve for a single family residential?
stickboy1375 is offline   Reply With Quote
Old 03-16-2013, 08:19 AM   #6
Licensed Electrical Cont.
 
Speedy Petey's Avatar
 
Join Date: Feb 2004
Location: NY State
Posts: 6,773
Default

residental 3-phase


Quote:
Originally Posted by av-geek View Post

Now, my ultimate question is are there any appliances that I can get for the home that will run on 3-phase?
NONE. Well, nothing that a normal home would use.


Quote:
Originally Posted by av-geek View Post
HVAC equipment is supposed to be much more efficient. How much savings would I get by running a 3-phase heat pump over a single phase? I am looking at upgrading that this summer. Howabout any other appliances?
3-phase is a bit more efficient, but nothing you'll ever actually notice on a bill.

I can guaranty you this, you will NEVER see a ROI on installing 3-phase to a home as an upgrade.
The only reason for having it would be if you had really big equipment that required it. Or, MANY pieces of equipment.
Besides, I would bet you'd likely be billed commercial once they brought it to your house.
__________________
Sometimes I feel like if I answer any more questions it is like someone trying to climb over a fence to jump off a bridge and me giving them a boost.
Answers based on the 2008 & 2011 NEC. If you're on the '14 already I feel sorry for you.
Speedy Petey is offline   Reply With Quote
Old 03-16-2013, 11:12 PM   #7
" Euro " electrician
 
frenchelectrican's Avatar
 
Join Date: Apr 2006
Location: WI & France { in France for now }
Posts: 5,369
Default

residental 3-phase


Quote:
Originally Posted by Speedy Petey View Post
NONE. Well, nothing that a normal home would use.


3-phase is a bit more efficient, but nothing you'll ever actually notice on a bill.

I can guaranty you this, you will NEVER see a ROI on installing 3-phase to a home as an upgrade.
The only reason for having it would be if you had really big equipment that required it. Or, MANY pieces of equipment.
Besides, I would bet you'd likely be billed commercial once they brought it to your house.
I agree with Speedy Pete just trust me I have three phase service at Wisconsin and I do get billed in commercal rates due it have incomming service on commeral side but the rate between the two is not really huge at all.

But if you have both single and three phase service there will be no question asked a very good chance you will billed higher rate or dual service cost.

Merci.
Marc
__________________
The answer will be based on NEC ( National Electrical code ) or CEC ( Cananda Electrical code ) or ECF ( Electrique Code France )
frenchelectrican is offline   Reply With Quote
Old 03-16-2013, 11:23 PM   #8
Idiot Emeritus
 
Join Date: Mar 2008
Location: Fernley, Nevada (near Reno)
Posts: 1,559
Default

residental 3-phase


Quote:
Originally Posted by Speedy Petey View Post
NONE. Well, nothing that a normal home would use.


3-phase is a bit more efficient, but nothing you'll ever actually notice on a bill.

I can guaranty you this, you will NEVER see a ROI on installing 3-phase to a home as an upgrade.
The only reason for having it would be if you had really big equipment that required it. Or, MANY pieces of equipment.
Besides, I would bet you'd likely be billed commercial once they brought it to your house.
This is true, if 3 costs much of anything, you'll never live long enough to recoup the investment with a basic average house. About the only thing that would use 3 here would be the A/C, and these days there's not much difference in efficiency. But 3 units are more reliable.

Around here some of the subdivisions built in the 70s had 3 to a lot of houses. They all had 240 delta services and the only load served by all 3 phases was the A/C. Back then there was quite a difference in efficiency, plus the 3 units were far more reliable. Some of them are still in operation.

If you have a well, I'd highly advise using 3. 3 Well pumps are more efficient, but the real seller here is that they seem to run forever with no problems. No start relays, no capacitors, just a simple contactor and overloads. Though some of us will install a phase failure relay, this insures that all 3 phases are valid before the motor starts.

Edit to add;

The 3 I have at my house is billed at the same rate as single phase would be. If I remember (it's been 14 years....), single phase would have cost $1700, and 120/208 wye cost $3600. With all the 3 stuff I have, phase conversion would have been slightly less than the difference, but I've more than made up for it in efficiency. With all the shop equipment, I have 22 3 motors.

Last edited by micromind; 03-16-2013 at 11:32 PM.
micromind is offline   Reply With Quote
Old 03-16-2013, 11:31 PM   #9
" Euro " electrician
 
frenchelectrican's Avatar
 
Join Date: Apr 2006
Location: WI & France { in France for now }
Posts: 5,369
Default

residental 3-phase


Quote:
Originally Posted by micromind View Post
This is true, if 3 costs much of anything, you'll never live long enough to recoup the investment with a basic average house. About the only thing that would use 3 here would be the A/C, and these days there's not much difference in efficiency. But 3 units are more reliable.

Around here some of the subdivisions built in the 70s had 3 to a lot of houses. They all had 240 delta services and the only load served by all 3 phases was the A/C. Back then there was quite a difference in efficiency, plus the 3 units were far more reliable. Some of them are still in operation.

If you have a well, I'd highly advise using 3. 3 Well pumps are more efficient, but the real seller here is that they seem to run forever with no problems. No start relays, no capacitors, just a simple contactor and overloads. Though some of us will install a phase failure relay, this insures that all 3 phases are valid before the motor starts.

Edit to add;

The 3 I have at my house is billed at the same rate as singly phase would be. If I remember (it's been 14 years....), single phase would have cost $1700, and 120/208 wye cost $3600. With all the 3 stuff I have, phase conversion would have been slightly less than the difference, but I've more than made up for it in efficiency. With all the shop equipment, I have 22 3 motors.
That one reason why I need three phase in first place due I have deep well ( it is over 200 meters down < about 660 feet > ) and have 15 CV pump to over come the head pressure with 1.5 inch discharge port. also I have emeregcy well which it is dual driven ( either electric or diesel unit on pto ) which it been used by Pomiers ( Fire dept ) from time to time.

Merci,
Marc
__________________
The answer will be based on NEC ( National Electrical code ) or CEC ( Cananda Electrical code ) or ECF ( Electrique Code France )
frenchelectrican is offline   Reply With Quote
Old 03-16-2013, 11:42 PM   #10
Idiot Emeritus
 
Join Date: Mar 2008
Location: Fernley, Nevada (near Reno)
Posts: 1,559
Default

residental 3-phase


Quote:
Originally Posted by frenchelectrican View Post
That one reason why I need three phase in first place due I have deep well ( it is over 200 meters down < about 660 feet > ) and have 15 CV pump to over come the head pressure with 1.5 inch discharge port. also I have emeregcy well which it is dual driven ( either electric or diesel unit on pto ) which it been used by Pomiers ( Fire dept ) from time to time.

Merci,
Marc
I'm lucky, my well is only 140' deep. 1.5HP pump. I just went out and looked; it has been run 2608 hours, and has started and stopped 91,576 times.
micromind is offline   Reply With Quote
Old 03-16-2013, 11:49 PM   #11
" Euro " electrician
 
frenchelectrican's Avatar
 
Join Date: Apr 2006
Location: WI & France { in France for now }
Posts: 5,369
Default

residental 3-phase


Quote:
Originally Posted by micromind View Post
I'm lucky, my well is only 140' deep. 1.5HP pump. I just went out and looked; it has been run 2608 hours, and has started and stopped 91,576 times.
I don't think any of single phase motours will last that long of number of start et stop cycle.

IIRC most uselly go out anywhere from 2,000 to 50,000 cycles depending on design of the motour and starting system.

I just texted my sister in wisconsin and she reply what my pump hours now it is at 5437 hours but I do not know how many start et stops but for pomiers that differnt story IIRC about 470 hours ( it have 6 inch discharge port so that why it can fill the tanker pretty fast )

Merci,
Marc
__________________
The answer will be based on NEC ( National Electrical code ) or CEC ( Cananda Electrical code ) or ECF ( Electrique Code France )
frenchelectrican is offline   Reply With Quote
Old 03-17-2013, 05:25 AM   #12
E2 Electrician
 
stickboy1375's Avatar
 
Join Date: Apr 2012
Location: Litchfield, CT
Posts: 4,633
Default

residental 3-phase


3 phase well pumps and VFD are very common now a days, people that live in the city and have a second home in the country do not like the water pressure change, so they generally get a VFD installed to accommodate this issue. I've yet to come across a house that would benefit from a 3 phase service, and doubt I ever will.

Last edited by stickboy1375; 03-17-2013 at 05:29 AM.
stickboy1375 is offline   Reply With Quote
The Following User Says Thank You to stickboy1375 For This Useful Post:
andrew79 (03-17-2013)
Old 03-17-2013, 07:15 AM   #13
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 6,839
Default

residental 3-phase


Quote:
Originally Posted by micromind View Post
Edit to add;

The 3 I have at my house is billed at the same rate as single phase would be. If I remember (it's been 14 years....), single phase would have cost $1700, and 120/208 wye cost $3600. With all the 3 stuff I have, phase conversion would have been slightly less than the difference, but I've more than made up for it in efficiency. With all the shop equipment, I have 22 3 motors.
I don't understand; could you show the calculations?

Quote:
Originally Posted by micromind View Post
Around here some of the subdivisions built in the 70s had 3 to a lot of houses. They all had 240 delta services and the only load served by all 3 phases was the A/C. Back then there was quite a difference in efficiency, plus the 3 units were far more reliable. Some of them are still in operation. .
I could see an apartment building where 120/240 delta 3 phase was available and all of the apartments were wired to balance any 240 volt only single phase loads using the B phase (high leg) leaving more of the A and C legs for the 120 volt loads. For a subdivision, another pole transformer is needed every 300 feet or so to avoid voltage drop issues so if there were no 3 phase loads then they would probably not have 3 phase service to the homes.
__________________
Stop wasting time re-adjusting the pattern. Have several lawn sprinklers, one for each pattern.

Last edited by AllanJ; 03-17-2013 at 07:31 AM.
AllanJ is offline   Reply With Quote
Old 03-17-2013, 07:44 AM   #14
Licensed Electrician
 
k_buz's Avatar
 
Join Date: Mar 2012
Location: SE Wisconsin
Posts: 4,336
Default

residental 3-phase


Apartment buildings are usually 120/208.
__________________
__________________________________________________ ______________
Answers based on the National Electric Code. Always check local amendments.


k_buz is offline   Reply With Quote
Old 03-17-2013, 12:13 PM   #15
Idiot Emeritus
 
Join Date: Mar 2008
Location: Fernley, Nevada (near Reno)
Posts: 1,559
Default

residental 3-phase


Quote:
Originally Posted by AllanJ View Post
I don't understand; could you show the calculations?


I could see an apartment building where 120/240 delta 3 phase was available and all of the apartments were wired to balance any 240 volt only single phase loads using the B phase (high leg) leaving more of the A and C legs for the 120 volt loads. For a subdivision, another pole transformer is needed every 300 feet or so to avoid voltage drop issues so if there were no 3 phase loads then they would probably not have 3 phase service to the homes.
If the service has 3 hots and a neutral/ground going into the weatherhead, it's 3. If one of the hots is smaller than the other two, it's a ∆. Most of these residential 3 services have a delta breaker in the panel. This is a 3 pole breaker that has 4 terminations. Basically a 2 pole breaker with a 3rd pole added on, and the 3rd pole has lugs for both in and out. The high leg goes into a lug on the breaker; the other two legs are fed normally. The result is all 3 phases on the load lugs.

I've seen quite a few apartments with 3 services, but every one of them had a 120/208 wye. Each unit had a single phase panel fed by two legs of the wye system.

I've also seen motels that had through-the-wall- HVAC units that operated on 20 amp 250 volt receptacles and the service was 240∆. The high leg and one of the other legs was used for the receptacles.

I wouldn't recommend connecting a residential stove or oven using the high leg of a ∆ service. Most of these appliances need 120 for the controls. VERY few resi electricians know anything about a ∆ service, and even fewer handyman types do. There'd be a 50/50 chance of getting the high leg on the control circuit, thus burning it up. Water heaters, baseboard heaters, receptacles that don't involve the neutral are all perfectly fine with the high leg, but not much else.

Rob

micromind is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
hELP! Amperage needed for 220V motors 1488rob Electrical 36 01-28-2014 04:44 PM
Three phase transformer question rongaudier Electrical 8 03-08-2011 07:19 AM
Wiring Single Phase through 3 Phase socket tonyr417 Electrical 10 10-26-2010 09:09 PM
Want to add a single phase Subpanel to three Phase Main meglomachinist Electrical 19 09-10-2009 03:46 PM
120/208/1 phase wiring questions JohnJon Electrical 11 08-31-2008 11:28 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.