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If you need 220v 3-phase power how many wires are required coming in from the transformer or power pole and what are the voltages or potential purposes of each wire load 110v load 220v neutral ground?
Wiki User
∙ 15y ago
In 120/208V 3 phase system you have 5 wires: three hots, one neutral, and one ground. You have 208V between any two hots and 120V between any hot and neutral. The neutral is the same as in a single phase system. Clarification: Only 4 wires maximum come from the pole - 3 phases and a neutral, and then only if the Transformers are on the pole. The ground is always locally derived from a ground rod(s) and/or cold water pipe ground. Most of the time, only 3 wires come in from the pole - the 3 phases in a Delta configuration (Delta has no neutral). The neutral is then derived from a local transformer connected in a Delta-Wye setup. The neutral is the center connection in the Wye. So, from the utility feeder to the transformer - 3 wires. From the transformer (wherever it is located) to the building service entrance panel - 4 wires. The ground is connected at the service entrance panel, and from there to the rest of the building you would have all 5 wires. Clear? In the US, 208/120 is a standardized mains voltage, but in some parts of the world, the phase-to-phase voltage is 220. In that case, the phase-to-neutral potential (in a 3-phase system) would be 127 Volts, not 120.
Wiki User
∙ 15y ago
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Is line voltage or phase voltage mentioned on transformer nameplate?
It depends how they are connected. If they are connected between line conductors then they are measuring line voltages. If they are connected across phases then they are measuring phase voltages.
What is the capacitive voltage transformer in sub station?
A coupling capacitor voltage transformer (CCVT) is composed of two stacks of capacitors which step the primary voltage down to a lower voltage potential transformer. These are typically used on 100kV and above, and the potential transformer is often around 15kV on the primary side. There are two reasons to use CCVTs over PTs (potential transformers) - at the above voltage levels, they are cheaper, and they can be used for power line carrier signal injection. Under transient conditions, CCVTs typically won't perform as well as PTs, and also may have worse accuracy ratings, so are often not acceptable for metering purposes.
How do i convert from 380 volts to 220 volts?
If these are the exact voltages that you need you will need an auto transformer to obtain these voltages. If these voltages are nominal voltages and are of a three phase four wire configuration, the 220 voltage can be obtained from the three phase legs to the neutral (ground) connection. The equation to use is 400/1.73 = 231 volts.
What is one of most common uses of transformer?
Both Current and Potential Transformer are instrument Transformers which are used to measure very high current and voltage respectivly. Current Transformer is a Step up transformer and used to measure high current, its secondry is connected to ammeter of very small capacity (usally 5 A) but its Scale is calibrated according to actul values. Potential Transformer is a step down tansformer and its secondry is connected to voltmeter of small range but again the scale is calibrated for actul values. So as a whole both Current and Potential Transformers are used to measure high values of Current and Voltage respectivly.
How efficient is a transformer when changing voltages?
A: Must understand this A transformer transfer power minus efficiency to another level that all it does.
How do you check a transformer for ac house unit?
Check that the input and output voltages are as required. Check that the transformer is big enough for the current required for the unit you have.
What is instrument potential transformer?
it is used to measure very high voltages which can not be measured with volt meter.
Can a distribution transformer be used as a potential transformer?
I'm not quite sure what you mean by a "potential transformer", but I look at it this way: The transformer isn't aware of the purpose to which you're putting it, so no matter what you call the function, the transformer continues to perform it ... transforming voltages and impedances in proportion to the turns ratio, and currents in proportion to its inverse.
How are lower voltages combined into higher voltages for transmission?
Low voltages are not 'combined into higher voltages' for transmission! The lower voltage (e.g. the voltage generated at a power station) is applied to the primary winding of a large power transformer, and the required higher transmission voltage then appears across the transformer's secondary winding. The magnitude of the secondary voltage is determined by the turns ratio of the transformer's windings.
High AC voltages are usually measured with?
They are usually measured using potential transformers that lower the voltages so that normal metering equipment can be used. Potential transformers PT's are almost no different that regular transformers except they are designed to be extremely accurate since they are used for metering purposes.
Is line voltage or phase voltage mentioned on transformer nameplate?
It depends how they are connected. If they are connected between line conductors then they are measuring line voltages. If they are connected across phases then they are measuring phase voltages.
What is the capacitive voltage transformer in sub station?
A coupling capacitor voltage transformer (CCVT) is composed of two stacks of capacitors which step the primary voltage down to a lower voltage potential transformer. These are typically used on 100kV and above, and the potential transformer is often around 15kV on the primary side. There are two reasons to use CCVTs over PTs (potential transformers) - at the above voltage levels, they are cheaper, and they can be used for power line carrier signal injection. Under transient conditions, CCVTs typically won't perform as well as PTs, and also may have worse accuracy ratings, so are often not acceptable for metering purposes.
How do i convert from 380 volts to 220 volts?
If these are the exact voltages that you need you will need an auto transformer to obtain these voltages. If these voltages are nominal voltages and are of a three phase four wire configuration, the 220 voltage can be obtained from the three phase legs to the neutral (ground) connection. The equation to use is 400/1.73 = 231 volts.
What is uses of tapped coil?
If question is about a transformer's tapped coil then the taps are a way of getting different voltages from one transformer. The end of the transformer's coil is the common point and the taps to this common point will give different voltages depending on where in the coil the taps are taken from.
What is one of most common uses of transformer?
Both Current and Potential Transformer are instrument Transformers which are used to measure very high current and voltage respectivly. Current Transformer is a Step up transformer and used to measure high current, its secondry is connected to ammeter of very small capacity (usally 5 A) but its Scale is calibrated according to actul values. Potential Transformer is a step down tansformer and its secondry is connected to voltmeter of small range but again the scale is calibrated for actul values. So as a whole both Current and Potential Transformers are used to measure high values of Current and Voltage respectivly.
How efficient is a transformer when changing voltages?
A: Must understand this A transformer transfer power minus efficiency to another level that all it does.
Is 3 phase star transformer has more winding than delta?
The # of windings in a transformer are based on the primary and secondary voltages the transformer is rated for not the way the windings are connected.
