Node (circuits) - Wikipedia, the free encyclopedia
`
`https://en.wikipedia.org/wiki/Node_(circuits)
`
`Node (circuits)
`
`From Wikipedia, the free encyclopedia
`
`In electrical engineering, node, refers to any point on a circuit where two or more circuit elements meet. For two
`nodes to be different, their voltages must be different. Without any further knowledge, it is easy to establish how
`to find a node by using Ohm's Law: V=IR. When looking at circuit schematics, ideal wires have a resistance of
`zero. Since it can be assumed that there is no change in the potential across any part of the wire, all of the wire
`in between any components in a circuit is considered part of the same node.[1]
`
`Voltage = Current * Resistance
`since voltage is a measure of potential difference, the voltage between any two parts of the same node is:
`
`Vab= (Current) * 0
`
`So at any two points on the same branch of the circuit, the change in potential difference is 0. Therefore,
`throughout the entire node the voltage is the same.
`
`In this circuit diagram the voltage in the
`green node is the same throughout,
`likewise, the voltages in the blue node
`and the red node are the same
`throughout.
`
`In most cases, the voltage difference
`between one point on a piece of metal
`(such as a copper wire), and the voltage
`at another point of the same piece of
`metal or on other bits of metal with
`metal-to-metal contact with the first
`piece of metal, is so small that it is usually considered insignificant. So every bit of that connected metal can be
`considered part of the same node.
`
`Each different color in circuit above is a different node
`
`Some notable exceptions, where the voltage difference is large enough to become significant, include:
`
`high-precision resistance measurements using a Kelvin connection
`the difference in voltage between ground and neutral, between the "neutral wire" and the "safety ground
`in a domestic AC power plugs and sockets, can be fatal. A properly installed electrical system connects
`them together at one (and only one) location, leading many people to the fatally incorrect conclusion that
`they are at "the same" voltage, or that the safety ground is "redundant and unnecessary".
`the Seebeck effect and the Peltier effect
`joints involving aluminium wire
`
`Dots used to mark nodes on a circuit diagram are sometimes referred to as meatballs. [2]
`
`References
`
`1.
`
`2.
`
`Smith, Ralph J. (1966), Circuits, Devices and Systems, Chapter 2, John Wiley & Sons, Library of Congress Catalog
`Card No.: 66-17612
`Mansfield, Michael; O'Sullivan, Colm (2010), Understanding Physics (2nd edition), Chapter 14, page 359, John
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`Node (circuits) - Wikipedia, the free encyclopedia
`
`https://en.wikipedia.org/wiki/Node_(circuits)
`
`Wiley & Sons
`
`Retrieved from "https://en.wikipedia.org/w/index.php?title=Node_(circuits)&oldid=698372696"
`
`Categories: Electricity
`
`This page was last modified on 5 January 2016, at 18:25.
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`2 of 2
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`4/18/2016 3:03 PM