Talk:Rogowski coil

disadvantages
Under disadvantages, it states: 'Traditional split-core current transformers do not require integrator circuits. The integrator is lossy, so the Rogowski coil does not have a response down to DC; neither does a conventional current transformer (see Néel effect coils for DC). However, they can measure very slow changing currents with frequency components down to 1 Hz and less.'

The last line is not clear. 'However, THEY can measure very slow changing currents...' I assume that the word THEY refers to either Rogowski coils or conventional current transformers, but it could also refer to only one of those. Can someone modify the text so that the meaning is clear?

An example would be, 'However, Rogowski coils can measure...', or 'However, both Rogowski coils and conventional coils can measure...' — Preceding unsigned comment added by Re34646 (talk • contribs) 15:44, 25 April 2024 (UTC)

quantitative description
I'm going to add some formulae for the response of the coil. I have references for these things, but I don't have full bibliographic info on those references. (Sort of - One's unpublished / distributed by the author; the other's from a published book, but all I have are photocopies of the appendix, not the title/ authors.) I'll check these against my own calculations before tossing it up, and do a quick web search for references.SMesser (talk) 14:21, 31 October 2008 (UTC)

rogowski coil image does not represent description
I noticed that the image for the Rogowski coil that accompanies the article has a terminal at both ends of the coil. The article claims the terminals should be at the same end of the coil. I'm not sure if having the terminals at a single end is a defining characteristic of the coil or just a feature that some coils may have - so this is confusing. Heathcd (talk) 12:38, 3 June 2008 (UTC)
 * There are diagrams on the other language wikis, like Rogowskispule. Also can copy info in.


 * Also you can combine a Rogowski coil (high-freq AC) with a hall effect current probe (DC to low-freq AC) for wideband measurements. — Omegatron 16:08, 27 March 2008 (UTC)


 * I think I can clarify - the terminals are at each end of a single wire, but that wire is often brought back through the torus formed by the windings. This helps to minimize electromagnetic interference.  It's difficult to draw clearly, so the return-through-torus wire is often omitted.SMesser (talk) 14:15, 31 October 2008 (UTC)


 * Hi all, i recently built a Rogowsky coil for a college project, based on the patent US-6313623-B1, where there are various diagrams and descriptions of both traditional and modern designs. I copied one of the drawings just for reference. Cheers. --Luque alfredo (talk) 20:58, 28 February 2011 (UTC)

Picture update
I've just uploaded a diagram of the Rogowski coil and linked to this article, as well as some expansion of the first paragraphs. Let me know if it needs correcting. Cheers. --Luque alfredo (talk) 00:48, 1 March 2011 (UTC) (Previous picture: [[Media:Rogowskis coil.png|Rogowskis coil]])

Request for an Update to the Diagram
Hi Luques alfredo! The diagram is great however it would be helpful, at least to me, if the variables in the diagram matched the ones in the "Formulae" section. For instance: your "r" in the diagram is "R" in the Formulae, your "i" in the diagram is "I" in the Formulae=, "a" in the Formulae is not shown in your diagram.

Also there is no discussion of the electronic integrator not integrating below a certain frequency, as set by the RC time-constant in the op-amp feedback circuit. Thank you for your kind consideration. -walt --Walt Rozanski (talk) 16:36, 24 May 2012 (UTC)

I will second this request-- there is a strong need for the equation to match the variables shown in the diagram. The "A" in the formula does appear, but the r and R are confusing and problematic. — Preceding unsigned comment added by Brianvon (talk • contribs) 21:33, 22 April 2016 (UTC)

Possible addition for Application and Disadvantages
As far as I understand from the article linked later, Rogowski coil is used in certain types of modern electronic energy meters. There has just been an article which notes that devices containing Rogowski coil are associated with "electronic energy meters [that can] give false readings that are up to 582% higher than actual energy consumption". "The inaccurate readings are attributed to the energy meter’s design, together with the increasing use of modern (often energy-efficient) switching devices. Here, the electricity being consumed no longer has a perfect waveform, instead it acquires an erratic pattern. The designers of modern energy meters have not made sufficient allowance for switching devices of this kind." 87.110.36.224 (talk) 20:34, 8 March 2017 (UTC) See also the original article and academic paper from the University of Twente

Formulae
The formula for inductance introduces a new variable 'a' which is not mentioned previously.I think this 'a' should be 'r' otherwise the units don't match and you get a complex inductance as R2 - A2 would be negative. — Preceding unsigned comment added by JayMoog (talk • contribs) 10:41, 27 November 2018 (UTC)
 * Done. Glrx (talk) 21:30, 25 December 2018 (UTC)