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What is the difference between single phase and three phase electrical power services?
Answer for USA, Canada and countries using similar 60Hz household electricity supplies This is a very simplified answer: Single-phase has two hot "legs". Each are 120 V. for a total of 240 V. A neutral wire (white in color) will give you 120 V. When straight 240V is needed, a neutral isn't necessary. 3-Phase has 3 hot legs for a total of 480V. This voltage is generally used for motors in industrial and commercial settings. This voltage can be "stepped down" via use of a step-down transformer. This converts 480V into 120/208/277. 120V is used for common appliances. 208V can be used for dryers and ranges (if they're rated for 208). 277V is used for lighting circuits (again, lighting must be rated for 277V). 3-phase is used in commercial and industrial, including schools. A neutral is needed for 120V and 277V and is generally gray.For more information see the answers to the Related Questions shown below.
Where does you neutral come from single phase transformer?
In a single phase system the neutral wire is the return path of the circuit and may be near ground potential, in multiphase systems it carries the unbalanced current.In a single phase system where only one "hot" wire supplies current to the load, the "neutral" wire completes the circuit and carries the current flowing from the load back to the power station.As always, if you are in doubt about what to do, the best advice anyone should give you is to call a licensed electrician to advise what work is needed.Before you do any work yourself,on electrical circuits, equipment or appliances,always use a test meter to ensure the circuit is, in fact, de-energized.IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOBSAFELY AND COMPETENTLYREFER THIS WORK TO QUALIFIED PROFESSIONALS.
How do you tell how many poles a 3 phase 480 volt motor has?
It is based on the RPM of the motor. Use the following formulas for 50 and 60 Hertz. The mathematical formula is Frequency in Hertz times 60 (for seconds in a minute) times two (for the positive and negative pulses in the cycle) divided by the number of poles. For 60 hertz, the formula would be, 60 x 60 x 2 = 7,200 no load RPM divided by the number of poles will give you the nameplate RPM of the motor. eg from above formula 7200/2 pole = 3600 RPM, 7200/4 = 1800 RPM, 7200/6 = 1200 RPM
What is the three phase voltage in America?
It varies by location and application. I will assume for this answer that we are talking low voltage (<1000 VAC): Grounded Wye Systems: 208/120 (Common) 480/277 (Common) 600/347 (Rare) Delta: 480 (ungrounded) 240/120 (grounded high-leg) 480/480 (corner grounded- rare and dangerous) The convention used above i.e. 208/120 designates the phase-phase voltage (208) and the phase to ground voltage (120). Some of the common Medium Voltage systems: 4.16 kV, 7.2 kV, 12.47 kV, 13.8kV
Will changing an electric motors input from 115 volt to 230 volt cause motor to run at 3450?
Yes, IF the motor is a dual-voltage motor to begin with. There should be re-connection instructions on the motor nameplate, or available from the manufacturer. The motor will list both voltages on the nameplate. If it only lists one, then the motor cannot be re-wired to a different voltage.
What is transformer tap changing?
A transformer that has part of one winding partitioned in such a way that it can be removed or added to the winding. For example, you may have a transformer with 100 turns on the low side and 1000 turns on the high side. If it were a tap changing transformer on the high side winding, you may be able to add or subtract 100 turns, so the turns ratio can be anywhere from 9/1 to 10/1. <<>> This type of transformer is in common use in home distribution systems. On the side of the transformer there is a handle with the markings of 14,400/7200. By having this ability to work on two different primary voltages the utility only has to stock one transformer. The same transformer can be connected to the grid across phases at 14,400 or phase leg to ground at 7200 volts. The transformer ratios are so wound that the output voltage remains at 120/240.
What is a tap changing transformer?
A transformer that has part of one winding partitioned in such a way that it can be removed or added to the winding. For example, you may have a transformer with 100 turns on the low side and 1000 turns on the high side. If it were a tap changing transformer on the high side winding, you may be able to add or subtract 100 turns, so the turns ratio can be anywhere from 9/1 to 10/1. <<>> This type of transformer is in common use in home distribution systems. On the side of the transformer there is a handle with the markings of 14,400/7200. By having this ability to work on two different primary voltages the utility only has to stock one transformer. The same transformer can be connected to the grid across phases at 14,400 or phase leg to ground at 7200 volts. The transformer ratios are so wound that the output voltage remains at 120/240.
What if you applied 14400 volts to a 7200 volt transformer?
Applying 14400 volts to a 7200 volt transformer would likely cause damage to the transformer. The transformer is designed to handle a specific voltage range, and exceeding that range can lead to overheating, insulation breakdown, and potentially a short circuit. It is essential to operate transformers within their specified voltage limits to ensure safe and proper functioning.
What is the kw input on a 50amp breaker with a 208v three phase electrical feed?
7200
Where does the neutral come from when turning 3 phase into single phase say in a street sub station?
In a split phase service, which is the standard for residences and very small businesses in the US, Canada, and some other areas, one transformer is connected to one phase of the three phase primary distribution mains. The secondary winding is centertapped, with the centertap grounded and called neutral. The other two phases are not involved at all. Do not call the hot legs of the service phases. They are not phases. They are opposite legs of only one phase. <<>> Canada and US transformer connections To best explain this, visualize the three primary line that you see on pole tops in industrial areas. The voltage between these three lines is about 12,460 volts. Eight feet below these top lines that is a single conductor. This conductor is grounded every three poles with ground rods and is used as a ground (neutral) on wye connections. When you see a pod of three transformers mounted together they are combined into a three phase system. From each of the three high voltage lines, the voltage goes through three separate fuses and down to a high voltage bushing in each of the transformers. Inside the transformer the voltage goes through a coil and exits the transformer through a second high voltage bushing. This bushing is tied into the grounded conductor (neutral) and then down to a grounding pad completing the circuit. This connection puts 7200 volts across the transformers primary coil (12460/1.73 = 7200. The secondary voltages of these transformers are determined by the customer that wants the three phase service. It could be 600,480 or 240 volts. Each single transformer has two output bushings. These bushings can be wired into either a delta or star configuration depending on what the customer ordered. In a single phase service, the name is derived from just using one of the three primary lines that are used above. It is the same primary connection, but the secondary is a bit different. The output secondary coil has three bushings coming out of the transformer. On the two outside bushings is the working voltage (house connections 240 volts). The middle bushing is a center tap of the secondary coil. This gives a voltage of (bushing left to center 120 volts) and (bushing center to bushing right 120 volts) The center tap of this transformer is grounded and connected to the single grounded eight foot lower conductor. The single phase service neutral is established at this point. These three secondary points are connected by triplex to the homes weather head where another connection is made to the homes service distribution. This is classed as a 120/240 volt service.
What is 7200 plus 7200?
7200 +7200 14400
What is 1.5 percent of 7200?
1.5% of 7200= 1.5% * 7200= 0.015 * 7200= 108
What is 6 percent of 7200?
6% of 7200= 6% * 7200= 0.06 * 7200= 432
Where are center tapped transformers used?
The transformer that feeds your house is a center tapped transformer. Primary 7200, Secondary 240. The 240 volt secondary is center tapped to give you 120 volts on either side of the tap. Hence house voltage is 120 / 240 volts.
What is 36 percent of 7200?
36% of 7,200 = 36% * 7200 = 0.36 * 7200 = 2,592
How many80s are in 7200?
There are 90 80s in 7200
What is the cubed root of 7200?
19.3097877³ = 7200 ■
