OT home service electric panel upgrade

I would like to get central air installed this
summer, my current service is too small
and out dated , also I need 3 phase power
to run my small lathes , compressor,
wood working stuff, There is 3 phase
on the poles in front of the house.
So I was going to ask if it is possible
to have my old service replaced with 3
phase panel, but can I still get 120/240
single phase for dryer and outlets from
the 3 phase box ? without transformer?
It would be like the 2 birds one stone
 
It all depends upon if the utility can and will connect your house to 3-phase power, and what the cost will be to install and what the monthly surcharge for 3-phase (if any), and what you are actually needing/willing to pay for.

That's who to ask FIRST.

Also, there are variations in voltage details depending upon if you would be served by a wye or delta 3-phase system.

Also, typically there is a TREMENDOUS difference in the cost of the actual main breaker panel between a common (and CHEAP) single-phase panel and a 3-phase panel. And, each individual 3-phase breaker AIN'T CHEAP!

Probably THOUSANDS of $$$ difference in the total installed prices of a common residential single-phase panel and a 3-phase panel and a handful of 3-phase breakers.
 
A friend has a good sized machine shop next to his house, on his residential service. He has a phase generator in the shop. I would guess based on what Bob has replied below, a similar set up might be more appropriate for you?

Commercial electric metering can be a real nightmare compared to residential.
 
Other people have done that to run a 5 HP CNC machining center setup to run unattended. I don't know the costs or how much it changed the basic charges on their monthly electric bills. There are many grain dryers that run 5 to 10 HP motors on single phase power. How many hours per week will you use three phase power?

Will you be using three phase power in the house? If you will use it in an outbuilding you may not need to run three phase power through the house. Are there other reasons the electrical panel in the house need replaced anyway? Either way, I would get some quotes and opinions from your local electricians.
 
Yes to answer your question 3phase and single phase can run from same box. Need to check on cost and any additional monthly surcharge for us its nothing but it appears some place do have a surcharge?
 
Check with your utility, but in many areas a three phase service gets billed at a commercial rate, whereas a single phase service gets billed at residential rate, which are much lower. As mentioned previously, a three phase panel and meter trim will also be quite a bit more expensive than a single phase.
As far as the voltages available from a three phase service - typically they are 120/208. Your single phase 120 volt circuits will be just that, but your single phase 208 volt circuits (two pole breaker, such as for your dryer) will be 208v instead of 240v. That won't bother your dryer - the heating element just won't get quite as hot. As far as single phase 208v loads, such as central air, most of the motors are dual rated anymore, so they can run on 208v or 240v.
All that being said, I think you would be better off installing a new single phase service, and getting a phase converter for your three phase loads.
Pete
 
What voltage are your 3-phase motors? ...If your motors are 230/240, but your supply is 208, you may experience a problem.

I was advised by our utility (208 3-phase) that they are allowed a 10% fluctuation in their voltage, so 208 can sometimes be at 190 volts, which is not good for a 230/240 volt motor. ....They strongly suggested we specify 200 or 208 volt motors when ordering new equipment.
 
Kevin, that's a valid question and usually electrical or legal questions draw out more opinions (including yours truly) then any other topic, SO LETS SEE WHAT HAPPENS

FIRST SHORT ANSWER sure IFFFFFFFFFFF the Utility (ask them not us) will even furnish you three phase service (very expensive for them and you both) it can be made to work BUT ID GUESS YOU WILL END UP WITH CONVENTIONAL 120/240 VOLT SINGLE PHASE THREE WIRE SERVICE (200 amps may suffice subject to your loads) AND USE A CONVERTER TO PROVIDE THREE PHASE FOR YOUR TOOLS that's a more typical, practical and cost efficient solution. Many with more power needs then yours use such.


You ask: There is 3 phase on the poles in front of the house. So I was going to ask if it is possible to have my old service replaced with 3 phase panel????????

ANSWER: YES its "possible" but the Utility may or may not even provide it and if so its very very expensive (you and them) as compared to 120/240 single phase household service.

You ask: but can I still get 120/240 single phase for dryer and outlets from the 3 phase box ? without transformer?

ANSWER: YES AND NO it depends:

(A) If you installed a 120/240 Volt Three Phase Four Wire Red/High Leg DELTA service you have 240 Volt Three Phase,,,,,,,,,,,, PLUS 240 Volt Single Phase,,,,,,,,,,,PLUS two legs of 120 Volt Single Phase

HOWEVER that's NOT for Billy Bob or Bubba or amateur wannabe electricians to install or use as they likely do not understand how it works or that the Red/High Leg is over 200 volts !!!!!!!!!! and how to balance the system.

(B) If you installed a 208 Y 120 Volt Three Phase Four Wire system you have 208 Volt Three Phase PLUS three legs of 120 Volt single phase

HOWEVER While some equipment works on 208 volts some does not do well THIS IS NOT MY RECOMMENDATION

(C) YES you could install dry transformers to obtain 120 or 240 volt single phase form other services if needed but that's expensive and inefficient THIS IS ALSO NOT MY RECOMMENDATION.


BOTTOM LINE ADVICE

1) Talk to your utility provider to see if they would even furnish it and even if so the costs and installation and equipment required ID ALMOST BET IF YOU TALK TO THEM YOU WONT END UP WITH THREE PHASE (Converter instead for your three phase tools) but sure its "possible" especially if money is no concern YEAH RIGHT LOL

2) Talk to an experienced competent electrician or electrical engineer plus local authority and compare what they say to any lay or even professional opinions posted here.

3) Determine you actual needs and three phase power requirements and shop around for three phase converters to power your tools.

Best wishes

John T Long retired electrical power distribution design engineer and rusty so no warranty (Consult electricians engineers the utility and local authority) the NEC has changed since I practiced
 
I think you will find out it's a lot easier and cheaper to put in a VFD for the three phase power. I have a cabinet shop in the country miles from three phase and I use a phase converter to run my equipment. Works great.
 
If you are only going to use 3 phase in a small shop, I don't think the power company will hook it up as it won't be profitable for them.
 
I have seen residential sections of towns with three phase power for air conditioning. If it is as simple as the power company changing your service drop or underground feeders then have at it. Unless other homes in the area have 3 ph the power company may not want to supply it. But ,hey if they do fine better than a converter. Cost of back box relatively the same cost of breakers a lot more {but how many three phase loads will you have]?
 
Not sure how your local utility works but around these parts you would need to be huge user to afford the up front costs, I have heard $10,000 and more. Check with your utility first as things might be different there.
 
Problem with those is each machine needs
one . and not sure if you can get 208/120
Out of a vfd ? As I have 2 machines
That need the 208/120,
 
I would bet the upgrade will be in the thousands, but worthwhile to check out.

Easiest way to get 208/120 to the machine is come off the 240 going into the VFD for the 120 and set the VFD for 208 out.
 

You might want to explore upgrading your single phase service.
And then just getting a 3 phase generator, natural gas or diesel for your shop equipment. Unless your using your three phase equipment for production 5 days a week, 8 hours a day.

You could even go so far as to get a genset that can supply both single and three phase. And it could do double duty as an emergency whole house genset.

Might work out to be more economical than going the power company route. And if you move out, you take it all with you.
 
Ok just called the utility and they said yes!
to the 3 phase and as it?s already on the
pole = no cost from utility. So I need to
start shopping for entrance panel and
breakers, I thank all of you for your
input
 
If you have an older elect system you will need to contact your electric company. They may have to install a bigger transformer.
 
(quoted from post at 18:46:56 02/09/18) Ok just called the utility and they said yes!
to the 3 phase and as it?s already on the
pole = no cost from utility. So I need to
start shopping for entrance panel and
breakers, I thank all of you for your
input
If it were me and they said yes, with no cost from utility over the phone, I would not start buying stuff before I made an appointment to have them come out for an engineering evaluation.
Or what ever they might call it. Then get something in writing as far as what they will supply and what you will supply.
 
My son bought a huge building that had 3 phase power already in it, but it was installed in about 1902 or older He had some 3 phase power tools so he had to update to todays standards. Starting with a new circuit breaker panel $550 instead of $129 for 200amp. Circuit breakers cost a lot more. Tho you can get 120/240 out of the breaker panel. Of course when you want 120/240 200ft away at the other end of the building, that's another panel. I think there are at least 5 circuit breaker panels through out the building. Then there are the monthly bills, His are $800 to $1000 a month turns out NYSEG charges more per KW for 3 phase in a commercial bldg.
My opinion, Update to a good 200 amp entrance and get or make a phase converter on wheels that you can use at the different machines
 

The previous posters have the topic thoroughly covered. Only consideration I can think of is to install a breaker panel that allows a simple reliable legal and safe connection to a standby generator.
A three phase panel will supply 208 to your 240V appliances. Not the best choice for 240V air conditioners or well pumps.
https://www.homedepot.ca/en/home/p.200-amp-combination-generator-panel-with-36-circuits-backup-and-80-circuits-total.1000722206.html
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top