Amperage Question 220V

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Old 09-01-10, 07:46 PM
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Amperage Question 220V

Here is my question. I have a 1000 watt (10 amp) HID light that comes with a ballast that I can switch from 110 to 220. I would like to run it on 220. I have a 4 wire 40 amp line that I would like to hook the light up too, but I do not know if this would be safe to do, my question is, what determines the amount of electricity that flows through a giving circuit? For example, a typical 110 15 amp line it is safe to plug in a 100 watt light bulb, so by that accord, does the light bulb determine the load of electrical current being drawn, or does the circuit breaker determine it?

If I can run a 100 watt bulb on a 110 15 amp line, shouldn't it be safe to install a 10 amp 1000 watt light to a 40 amp 220v line ?
 
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Old 09-01-10, 07:58 PM
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I posted on your other thread, but you are asking different things here.

You cannot power a 10amp light off a 40amp circuit.
 
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Old 09-01-10, 08:28 PM
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Your amperage is inversely proportionate to voltage. Voltage goes up, amperage goes down by the same value. You'll have to reconfigure the breaker set up as Mark says. It begs to question, why do you want to change the voltage of the light fixture? You won't be saving anything.
 
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Old 09-01-10, 09:10 PM
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my question is, what determines the amount of electricity that flows through a giving circuit?
The transformer on the pole feeding the panel. 120v is single phase and 240 is 2 phases/legs of 120v.

The higher the voltage the lower the bill because it pulls less amps(amperage). If that ballast will allow 240v feed, you will need a 2 pole 15 breaker for it.

does the light bulb determine the load of electrical current being drawn, or does the circuit breaker determine it?
The light bulb because it is pulling the load. The breaker determines how much of a load the breaker will allow.

shouldn't it be safe to install a 10 amp 1000 watt light to a 40 amp 220v line ?
No, 40 amp is way overkill. You only need a 15 amp breaker if its pulling 10 amps.. Make sure that ballast will accept a 240v load though or you will have a big problem.
 

Last edited by SilverTattoo; 09-01-10 at 09:23 PM. Reason: typo
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Old 09-01-10, 09:27 PM
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The transformer on the pole feeding the panel. 120v is single phase and 240 is 2 phases/legs of 120v.
Sorry, but wrong. Do not confuse a three-wire 240/120 volt circuit with two-phase. More likely as not you have never seen a two-phase system. The residential standard of 240/120 volts is single phase from a transformer with a center tapped secondary winding, the center tap being grounded. From one end of the transformer secondary to the other end you will have 240 volts, from either end to the center tap you will have 120 volts.
The higher the voltage the lower the bill because it pulls less amps(amperage). If that ballast will allow 240v feed, you will need a 2 pole 15 breaker for it.
Ignoring voltage drop you are wrong again. Electricity is billed by POWER consumed. Power is amperage multiplied by voltage and measured in watts. Assuming any particular piece of equipment running it on 240 volts will take one-half the amperage of running it on 120 volts but the power consumption is the same. Understand that with heating equipment you MUST take into consideration the resistance of the load.
 
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Old 09-01-10, 09:48 PM
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Sorry, but wrong. Do not confuse a three-wire 240/120 volt circuit with two-phase. More likely as not you have never seen a two-phase system. The residential standard of 240/120 volts is single phase from a transformer with a center tapped secondary winding, the center tap being grounded. From one end of the transformer secondary to the other end you will have 240 volts, from either end to the center tap you will have 120 volts.
Its single phase just like I said and it is also 2 legs/or phases pending on your terminology OF 120V. A+B is 240!!! A or B alone to ground is 120V.....

Ignoring voltage drop you are wrong again. Electricity is billed by POWER consumed. Power is amperage multiplied by voltage and measured in watts. Assuming any particular piece of equipment running it on 240 volts will take one-half the amperage of running it on 120 volts but the power consumption is the same. Understand that with heating equipment you MUST take into consideration the resistance of the load.
Lol dude stop googling your answers. Voltage drop has nothing to do with anything at all here. The OP mentioned nothing as to distance to the lamp to indicate anything about voltage drop and sizing wire accordingly for that. What are you even talking about?
 

Last edited by french277V; 09-02-10 at 12:34 AM. Reason: remove bad name calling
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Old 09-01-10, 10:56 PM
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Your use of the word PHASE is incorrect. It cannot be two phase and single phase at the same time.

I Googled nothing! You stated that using a higher voltage would result in lower bills. That is absolutely WRONG!

Nor do I appreciate your insulting twist on my screen name.
 
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Old 09-01-10, 11:11 PM
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You know nothing obviously. Phase is correct terminology just as is leg.. Its single phase with a A phase/or leg and B phase/or leg but, its still single phase SERVICE. Just as a 3 PHASE service... A PHASE, B PHASE AND C PHASE.. Any electrician knows this and I really dont know why I am wasting my time with you.

You stated that using a higher voltage would result in lower bills. That is absolutely WRONG!
Your absolutely crazy! Go recheck Wikipedia again. The higher the voltage, the LESS RESISTANCE.... WHICH IN RETURN IS LESS AMPACITY, which equals less $$$ This is why commercial is majority 208y/120 or 277v/480.... not 120v/240 like ressy that and the demand for more power and use of motors and devices that require a 3 PHASE SERVICE!!!
 

Last edited by french277V; 09-02-10 at 12:35 AM. Reason: remove bad namecalling
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Old 09-01-10, 11:53 PM
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Silver Tattoo if you will take out your electric bill you will see you are charged for kilowatts not kiloamps.

The modern residential service is 240 volts single phase pluse a grounded center tap from the transformer. 120v is obtained by using the center tap and one leg of the 240v.
 
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Old 09-02-10, 12:33 AM
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Silver.,

Please knock it off that is getting close to cross the line with namecalling If that happend you know the conquese is.

I have to edit one part so don't EVER do that with long time members here!

The power company will bill you in watts it don't matter what voltage you are running on It the same way in France as well they will billed by KWH rates and the meter will read in watt useage.

That is a fact for resdentail metering the commercal metering is diffrent ball of game to deal so just leave this part out for now. { not related to the DIY part at all }

The run of mill 120/240 volts is a single phase centre tapped transfomer end of discussion that is a fact.

Also the HID bulb do draw the load but do not ever forget the ballast they will add up the load as well so with 1 KW HID luminaire typically use total from anywhere from 1060 to 1175 watts total depending on type of ballast.



Now to OP .,

There are few codes related issue you can not use the 240 volt luminaries on 40 amp circuit espcally in resdentail side it is NOT allowed.

It have to be on 15 amp or 20 amp circuit depending on what size conductor you used and type of receptales.

And check the ballast connection to make sure you are on proper voltage due most of the HID ballast will have multi tap ballast { it will work up to 4 diffrent voltage setting }


Merci.
Marc
 
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Old 09-02-10, 09:22 AM
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kilowatts is what your billed yes which is 1000watts which is created from amps.************* The more AMPS!!!!! a device pulls or LOAD,the more its gonna cost you!! END OF STORY!

p = i x e or P=IE

Try learning OHMS LAW!

"When one ampere flows through a difference of two volts, two watts must be used. "
 

Last edited by Shadeladie; 09-02-10 at 10:57 AM. Reason: Removed comment
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Old 09-02-10, 09:52 AM
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Originally Posted by SilverTattoo View Post
Try learning OHMS LAW!
An EXCELLENT suggestion, I suggest you follow it!
 
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Old 09-02-10, 09:56 AM
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Originally Posted by SilverTattoo View Post
kilowatts is what your billed
Electricity is billed in kilowatt-hours (kWh), a unit of energy. Voltage, current and time are all components of calculating energy, and none of the three alone is enough to determine what is more or less expensive.

I don't know if you got up on the wrong side today or what, but please stop trolling these threads with insults and unhelpful comments.
 
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Old 09-02-10, 12:32 PM
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I am no trying to spam or troll so save that for someone else. I am making a point and I am not alone in that point.

OK to use 230V switch on power supply? - TechSpot Troubleshooting
 
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Old 09-02-10, 12:57 PM
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Silver, did you read the responses to that article you linked to? Those responses along with several different posters on this forum have shown you where your thinking has gone awry.


Electricity is sold by the kilowatt hour which is defined as the number of kilowatts of POWER multiplied by the number of hours. POWER, as defined, is the product of voltage times amperage. You already know this but what you are failing to see is that for any given load when the applied voltage is increased the resulting current flow decreases. The product of voltage multiplied by current stays the same and therefore the POWER consumed is also the same.

The old tale of a kilowatt hour meter only "reading" the higher current flow of the two "hot" legs is just that, and old tale with no truth behind it.

Assuming equipment that is designed for use at two voltages the ONLY time it will make a noticeable difference in the cost of POWER for operation is when the amperage drawn is sufficient to cause a significant voltage drop in the supplying conductors.
 
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Old 09-02-10, 12:59 PM
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Originally Posted by SilverTattoo View Post
I am no trying to spam or troll so save that for someone else. I am making a point and I am not alone in that point.

OK to use 230V switch on power supply? - TechSpot Troubleshooting
Silver, you know the formula power = Volts * Amps

A light has a Watt rating, let's use 1000 Watts as an example. Let's say it can be wired at 120 V or at 240 V.

At 120 V, the light will draw 1000 W / 120 V = 8.333 Amps

At 240 V, the light will draw 1000 W / 240 V = 4.167 Amps

Notice that the power in Watts consumed by the light is the same no matter which voltage is supplied to it. This is because the resistance of the light is fixed, and does not change with a change in voltage.

Residential utility meters bill on kilo-watt-hours only, not just on amps. So, since the watts are the same no matter which voltage is supplied to the light, the electric bill will be the same no matter which voltage is supplied to the light.
 
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Old 09-02-10, 01:04 PM
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Originally Posted by SilverTattoo View Post
I am no trying to spam or troll so save that for someone else. I am making a point and I am not alone in that point.

OK to use 230V switch on power supply? - TechSpot Troubleshooting
But lots of ignorance in that reference. For example:
Dryers run at 220V @60Hz which is actually just two separate 110V lines
Which is of course untrue. It uses the 240 volts supplied to your house. Also some spot on correct statements which support what others have been writing here.
Definition:
"In electrical terms, one watt is the power produced by a current of one ampere flowing through an electric potential of one volt.,,,Amps are still amps regardless of the voltage, watt/voltage = amp. A PSU at 230V vs 110V will still draw the same current.... Amp * voltage = watts....Running a computer at 240V vs 120V will not make any difference in power consumption, at least that would actually be noticeable on a power bill.
 
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Old 09-02-10, 01:13 PM
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The posters in that thread have a pretty fundamental misunderstanding of energy and power as it relates to current and voltage.

A constant power load, in this case the HID ballast, uses 1000W of power, regardless of the input voltage. As voltage goes up, current goes down, but power does not change:

1000W / 120V = 8.33A
1000W / 240V = 4.17A
1000W / 480V = 2.08A

To compute the amount of energy to run this light, you take the power in watts (1000W), divide by 1000 to get kilowatts (1kW), then multiply by the number of hours the light was on (say 10 hours).

1 kW * 10 hours = 10 kWh

The average price of energy in the USA is about $0.12 / kWh so it would cost 10 * 0.12 = $1.20 to run this light for a ten hour night. Every night for a month (times 30), this light will cost about $36 per month to run all night every night no matter what the ballast input voltage is.

There can be some initial cost savings with higher voltages because you can use smaller wires due to the lower current, but in this case it does not matter because you would need to run #14 in any case. Higher voltages also have slightly less voltage drop (waste heat) so it would be a little cheaper in the long run (probably around 0.5-1%).
 
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Old 09-02-10, 02:07 PM
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Silver, here's an exercise for you.

A person installs an electric water heater. This person requires a certain total amount (gallons) of water at 135 degrees F. every day but does not necessarily need to the total flow at any one particular time. He installs a heater rated at 4500 watts at 240 volts. He has the option of running either a 120 volt or a 240 volt branch circuit to the heater. The service panel, rated at 200 amperes 240/120 volts single phase is located less than ten feet from the water heater.

1. Which voltage will result in lower operating costs?

2. What would be the effect of using the other voltage?

3. What is the calculated amperage if using 240 volts?

4. What is the calculated amperage if using 120 volts?

The answers are calculated using variations of Ohm's law. The answers might surprise you.

(While the answers might be found in Wikipedia or a Google search I did not use either of these in formulating the exercise.)
 

Last edited by Furd; 09-02-10 at 02:43 PM.
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Old 09-02-10, 05:10 PM
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Dang, I hate working for a living. Missed all the fun! But you guys nailed it several times on the head.
 
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Old 09-02-10, 05:26 PM
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Ha! Silver is having a hard time seeing the forest through the trees.
 
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Old 09-02-10, 06:12 PM
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Sometimes you have to un-learn before you can learn.
 
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Old 09-02-10, 06:51 PM
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I see what is being said/typed but, I still am not 100% clear on this. I will talk with my foreman on this tomorrow( hes a Master Electrician). My understanding was that the less amps pulled, the better on the bill. I see the watts are staying the same in the equations regardless of the voltage but the amperage is lower with a higher power. Maybe the trees are getting in the way of my view of the forest here but this is what I was always told and taught. Regardless of ressy or comm should it not be the same story?

If the below is true.. What is the benefit other than lower energy consumption? Was I mistaking "cheaper" as in cost in material for electrical bill perhaps?

1000W / 120V = 8.33A
1000W / 240V = 4.17A
1000W / 480V = 2.08A

Furd
Ok im not sure about the codes on this one being 10 ft from the panel first of all.
1. 240 V is my answer
2. more energy efficient
3. 18.8 amps
4. 37.5 amps

running either a 120 volt or a 240 volt branch circuit to the heater
there is no 240 volt branch circuit. It is 2 branch circuits of 120v. 240 is 2 phase/legs/A+B, 120 is single A or B. ;}
 

Last edited by SilverTattoo; 09-02-10 at 07:54 PM. Reason: furd
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Old 09-02-10, 07:00 PM
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The advantage to higher voltage as you have shown above allow for smaller size circuits to be utilized. Smaller circuits mean smaller wire sizes and smaller conduit. Smaller conduit installs faster.
 
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Old 09-02-10, 07:20 PM
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Silver, I'm going out in a few minutes to have dinner with my sister. I don't know what time I will get home so I will give you the answers along with the calculations either late tonight or tomorrow. You might want to check your answers, though.

And don't worry or be defensive when you are wrong, if we never made any mistakes we would probably never learn anything new.
Also remember that some people that state they have thirty years of experience really have one year of experience thirty times over. Beer 4U2
 
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Old 09-02-10, 07:32 PM
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Yup have a good time. Sorry for being short with you. I am still going over all this stuff. Beer 4U2
 
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Old 09-02-10, 07:51 PM
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Silver you are thinking of the house being supplied with two 120v feeds. It isn't. It is supplied with 240v. The 120v comes from a center tap on the supplying transformer.

Also you may want to read this: Two-phase electric power - Wikipedia, the free encyclopedia
 
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Old 09-02-10, 08:01 PM
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I dont know the windings in the transformer on my pole outside but coming into my meterbase and into the panel is to legs of 120v. With a muiltmeter it read from A to ground aprox 120 same from B to ground or N (bonded same thing). A+b reads 240v. I have never even seen a wire (single cable) with a 240v reading on it, only 120 or 277V on a single then 240,208,480 AB, BC, AC, etc. So I do not see how its coming in as 240v.

P.S. Im not saying you are wrong or anything I am just saying. Ill read more it later and I got some questions for my boss tomorrow. Later
 

Last edited by SilverTattoo; 09-02-10 at 08:47 PM.
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Old 09-02-10, 08:49 PM
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POCOs’ aim to deliver point of supply (nominal system voltage) of 120v/240v to the residential customer which is higher than the voltage rating of the equipment (utilization voltage). While POCOs’ engineer and build their system’s differently which creates different variations around the targeted 120v/240v, these ranges are fairly tight, and within a 3%-5% band of the nominal system voltage (there are factors other than voltage which also effect power quality). This means that a person taking a voltage reading at their main panel may find a voltage reading between 114v and 126v (assuming a 5% deviation from target) {European Standards: 230v +/- 10%}. This will not be a constant reading 24/7 as load on POCO’s system causes normal voltage fluctuations. While POCO’s have various regulating equipment at power plants, transmission lines, substations, and distribution lines to keep nominal system voltage at target, today’s equipment is incapable of perfect precision given a complex electrical system. Another factor is that the homeowners’ volt meters are also not perfectly precise instruments, although some are more precise than others.

If it’s a generalized discussion and I read a reference to 110v/220v, I assume the person is using nameplate or electrical packaging terminology, and believe they mean 120v/240v. If it’s not a generalized discussion and a poster reports a voltage reading at their panel outside the 114v-126v range, that should raise a red flag as it may indicate a low or high voltage problem on POCO’s side. Frankly, if I was getting a number of readings at the very low end or high ends of the range, this would make me look more closely during periods of peak and non-peak loads. My home’s nominal system voltage fluctuates between 117v-122v. The lower end readings mostly occur during late afternoons/early evenings (peak loads) whereas the higher end readings most often occur between 11:00 p.m-6:00 a.m. The proximity of a customer to a substation generally results in a slightly higher voltage reading as compared to more distant customers, especially for those who are at the end of a feeder, or lateral.
 
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Old 09-02-10, 09:03 PM
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Old 09-02-10, 09:18 PM
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I have never even seen a wire (single cable) with a 240v reading on it
Silver, it may not be common in your area, but ask your boss if you have any older 240 volt 3 wire 3-phase systems in your area. In my area, a 240 volt Grounded "B" phase 3-phase system used to be pretty common, not so much any more. With this system A to B, B to C and C to A all read 240 volts. Phase to ground reads 240 volts, except for the Grounded "B" phase. We also used to see a lot of the same type 3-phase systems at 480 volts. Phase to phase and phase to ground is 480 volts. A lot of the newer guys in the trade really stumble when they run across one of these older systems till they learn and understand them. It was very common for smaller commercial buildings and restaurants to have two services, a single phase and a three phase.
 
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Old 09-02-10, 09:56 PM
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I know Ray did mention the two phase supply in the link and that is one of very unuseal item and I am one of few electricians that can actually understand the system.

The true two phase system will come in three flavours.,

Three wire two phase the common phase will be common for both { the amprange will be much higher than other two useally1.41 X of other phase.

four wire two phase system it will have phase A1-A2 and B1-B2 but no netural at all

Five wire two phase system it will have same with four wire two phase but it have netural and it can get tricky to read the voltage if not carefull.

The true two phase system is just about complety gone very few spots still have it I know couple spots in Wisconsins still have it we converted by scott-tee transfomer hook up which it will covert from three phase to two phase supply.

In France it about 100% gone on old two phase supply.

Now Silver as other gave you a very good point here just think it over and you will learn something along here.

Merci.
Marc
 
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Old 09-02-10, 10:18 PM
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The power example in one of the prior posts doesn't apply to every application. For example, if you apply 120V to a 60W light bulb, 0.5 amps of current will flow, but if you increase the voltage to 240V, twice the amount of current (1 amp) will flow and you'll burn out your light bulb. Things change whether you're talking about a resistive load or inductive/capacitve loads, which leads to true, reactive, and apparent power.

Silver, if I'm understanding you correctly, you are reading 240V between "phase A" and "phase B", which is correct. The "single" cable feeding your home has three conductors in one cable (two 120V lines and a ground). Reason the two lines add to 240V is because they are 180 degrees out of phase and are therefore additive.
 
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Old 09-03-10, 07:25 AM
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Originally Posted by mossman View Post
Silver, if I'm understanding you correctly, you are reading 240V between "phase A" and "phase B", which is correct
Other posters have tried to correct OP when using the terminology of "phase A" and "phase B" when referring to his two 120v hot legs. I agree w/ them. First, its an incorrect usage of term, and while it may not cause a serious problem when working from a single phase transformer since the secondary hot legs will be in phase, getting into a bad habit of incorrectly using the term could lead to serious problems should that person ever encounter a real 3-phase situation.

Perhaps understanding the 3-phase system used by POCO’s would help enlighten. Bulk transmission lines and distribution feeder lines coming out of substations are built as 3-phase lines consisting of ‘A’, ‘B’, and ‘C’ phases. These are most often seen along major roadways, and within industrial/commercial areas. Most 3-phase usage involves industrial and commercial complexes w/ 3-phase equipment. Large industrial and commercial users of electricity such as industrial manufacturers, regional shopping malls, hospitals, and even extreme high rise residential condos will have 3-phase service feeding the complex, and may have more than one primary feed to provide back-up power should one feeder go down. Even though a tall residential condo tower (sometimes it’s a mixed use property with businesses/offices toward the bottom floors and residential condos having the top floors) may have 3-phase primary feed into the building complex, the electrical delivery to each condo will be 120v/240v unless that customer has special electrical requirements and doubtful they would since stuff like elevators, heating and A/C are generally viewed as ‘common’ property of the building itself.

In terms of single family homes, there can be a 3-phase primary line running through a community but most often it’s one single primary line. This may be viewed by utility workers as a primary trunk line feeding the community if it’s directly tapped from a 3-phase primary line. At that interconnection point, it is irrelevant to the homeowner or inside electrician working on a single phase feed whether the utility worker made the connection to ‘A’, ‘B’ or ‘C’ phase. This single phase primary trunk line is usually tapped a multitude of times to create primary lateral lines, and those lateral taps will all be in phase since initially tapped from only one phase. That is why using "phase A" and "phase B" to refer to the hot legs is wrong, and confusing.
 
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Old 09-03-10, 12:48 PM
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Originally Posted by SilverTattoo View Post
I dont know the windings in the transformer on my pole outside but coming into my meterbase and into the panel is to legs of 120v. With a muiltmeter it read from A to ground aprox 120 same from B to ground or N (bonded same thing). A+b reads 240v. I have never even seen a wire (single cable) with a 240v reading on it, only 120 or 277V on a single then 240,208,480 AB, BC, AC, etc. So I do not see how its coming in as 240v.

P.S. Im not saying you are wrong or anything I am just saying. Ill read more it later and I got some questions for my boss tomorrow. Later
The legs of residential service is technically called split phase. It's two halves of one phase. There is only one sine wave, 208v peak to peak.. A-N is the top half, N-B is the bottom half of the wave. They are offset 180 degrees.

With 3 phase, there are 3 completely separate sine waves, each wave 240v (or 480 or higher) peak to peak. A-B is offset 120 degrees from B-C, which is offset 120 degrees from A-C. This produces a much smoother and more efficient source of power for devices designed to operate on it.

Where this really comes into play is in the efficiency of high power motors. Rather than having a single set of windings, 3 phase motors have 3 sets, each spaced 120 degrees apart (to match the offsets of the sine waves). The windings get energized in sequence as each phase peaks. Since the (invisible to the eye)"slow down/speed up" you would get with a single phase is minimalized, the motor is more efficient and (in theory) costs less to operate. I think that's what you are trying to get at and where you are confused.

Here.. If you look at this picture, it shows what 3 phase Wye power looks like. Any wave by itself would be considered single or split phase. It is important to note that all of the waves have a top peak and a bottom peak around the 0 line in each cycle. In split phase, the top peak is one 'leg' and the bottom peak is the other leg. In 3 phase, the other two waves 'fill in' the time where the single wave is on its opposite peak, which 'smooths' the power. So looking at the blue wave (single phase), all of the time where the wave is between peak and 0, the motor is slowing down, and between 0 and peak it is speeding up. Having the other two waves means the motor is only slowing down on one wave until another wave crosses it (rather than going all the way to the 0 line).



I hope this helps. 3 phase is tricky to explain in plain english as to why it works the way it does.
 
  #36  
Old 09-03-10, 12:53 PM
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Ok i spoke with my boss and you guys are right. The motors are 180 degrees out of phase on 120/240 service so there is really no benefit in a residential setting. Its a little different with commercial though and can be cheaper running higher voltage (3 phase) though its really just more practical like with a building with lots of motors they would run longer and cooler at a higher voltage than a lower voltage and its cheaper in material as well.

As far as the service coming into a home it is two phases/legs of 120v from the POCO. It is not one wire with 240vs on it with the winding at 180 degrees and when the are at the exact opposite side you get 240Vs. With 3 phase the windings are 120 degrees out of phase and it makes a full circle at 360 degrees on a 3 phase set up. On a 120/208 the winding are i think he said 120v and 88v to make 208vs, though at the panel it will not read 88v its in the transformer. Its 120 per phase and any 2 phases makes 208v from a y configuration.

P.S. The split phase (2 phase ) are Merc stated is basically obsolete and non existent. He told me he has worked with it but its very rare. Its just now simply single phase 3 wire service and the terminology is all the same legs/phases/a or B/ etc. It really just depends on what part of the woods you are from but its really all the same. My panel actually reads A and a B phase and I am well aware that its single phase service. Its just a terminology thing like a GFCI being called a GFI or a pigtail being called a stinger. For the record I am a commercial electrician with about 5 years experience and work with this all this time and do this all the time like my boss said I just really did not have a accurate or full understanding on the elements that make it work. Doing it and working with it are one thing and then understanding the logistics of it are another. I am still learning on both.

I understand now and I do appreciate the info from all and like my boss told me this is a common misunderstanding about high voltage so i dont feel as stupid but now i know.
Thanks again and sorry for being short with you people, I apologize for that.

So looking at the blue wave (single phase), all of the time where the wave is between peak and 0, the motor is slowing down, and between 0 and peak it is speeding up. Having the other two waves means the motor is only slowing down on one wave until another wave crosses it (rather than going all the way to the 0 line).]
He explained this to me as well i just didnt put it in my comment here. I was off today(lack of work) and went to pick up my pay check and we sat down and talked all this out and he drew out all these charts and stuff for me so I got a lot better grasp on this now. Thanks again.
 

Last edited by pcboss; 09-03-10 at 01:23 PM. Reason: fixed quote format
  #37  
Old 09-03-10, 01:26 PM
J
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It is not two PHASES, it is two LEGS of ONE phase. That is called 'SPLIT PHASE'. Your breaker box does not say PHASE A and PHASE B, it just says A and B, referring to LEG A and LEG B. LEG DOES NOT ALWAYS EQUAL PHASE. Single phase and Split phase are the same thing. Two phase is NOT.

PLEASE. Learn proper terminology. It is VERY confusing to everyone when you don't use it.
 
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Old 09-03-10, 01:26 PM
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Thank you for admitting that the posters here were correct. There are many knowledgeable people that contribute to this board including some licensed electricians.

I hope that you will continue to learn and ask questions.
 
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Old 09-03-10, 01:34 PM
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Jersy Matt

The man who pays me and holds a MASTERS LICENSES and is fine with my terminology as the rest of our crew here to. You are nit picking this to death. If you work in it its not confusing. Lust like 3 PHASE ABC phase AB or C or LEG ABC is all the same. Unless you are a wireman up on the power lines hanging transformers its not a big deal as you want it to be.

Thanks Im done with this thread.
 
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Old 09-03-10, 01:41 PM
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Thanks for coming back to complete the discussion.

Originally Posted by SilverTattoo View Post
Its a little different with commercial though and can be cheaper running higher voltage (3 phase)
Yes it can be cheaper to go at a higher voltage when you have the option. The install is cheaper because you can use smaller conductors and conduit, theoretically less labor. It can also be cheaper in the long run because higher voltage has less voltage drop which is all energy lost to waste heat. On small motors it's not a big deal because the totals watts is low, but on a big motor you could lose several kW to heat. This heats up the motor (wear and tear) and also heats up the building which adds to cooling cost if there's AC.
 
 

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