Editing Rogowski coil (section)

==Advantages==
This type of coil has advantages over other types of [[current transformer]]s.
 
* It is not a closed loop, because the second terminal is passed back through the center of the toroid core (commonly a plastic or rubber tube) and connected along the first terminal. This allows the coil to be open-ended and flexible, allowing it to be wrapped around a live conductor without disturbing it. However, positioning of the measured conductor is important in that case: It has been shown that, with flexible sensors, the effect of the position on the accuracy ranges from 1 to 3%. Another technique uses two rigid winding halves with a precise locking mechanism.<ref name=":2" />
* Due to its low [[inductance]], it can respond to fast-changing currents, down to several nanoseconds.<ref name=":3">Slawomir Tumanski, ''Handbook of Magnetic Measurements'', CRC Press, 2011, {{ISBN|1-439-82952-7}}, p. 175.</ref>
* Because it has no iron core to saturate, it is highly linear even when subjected to large currents, such as those used in [[electric power transmission]], [[welding]], or [[pulsed power]] applications.<ref name=":3" /> This linearity also enables a high-current Rogowski coil to be calibrated using much smaller reference currents.<ref name=":1" />  
* No danger of opening the secondary winding.<ref name=":3" />  
* Lower construction costs.<ref name=":3" />  
* Temperature compensation is simple.<ref name=":1" />  
* For larger currents conventional current transformers require an increase of the number of secondary turns, in order to keep the output current constant. Therefore, a Rogowski coil for large current is smaller than an equivalent rating current transformer.<ref>Stephen A. Dyer, ''Wiley Survey of Instrumentation and Measurement'', John Wiley & Sons, 2004, {{ISBN|0-471-22165-1}}, p. 265.</ref>