Technikatörténeti szemle 5. (1970)

KÖZLEMÉNYEK - Rajnai Rudolfné: Újabb adatok a transzformátor történetére vonatkozólag

486 TB* r^IWRA^W JOl^AI. AK» ELECTRICAL REVIEW. 9, 1889. p + » + ' Sifesult, o( course, less thaa the former. -. . The coaditions necessary to obtain the bnUii.o would be volt* (/J being constant', 0r

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00 R ~~~~afcjtis {B beingconstant), which iairorx>$sible.for one or « cells in scries. Oi* again, a standard cell of lower E.M.F, could be used ; or better etill, a. resistance added to the blide-wire which, per *e, having so Sow a rpsystautso, hHs not sume-lent diiferwace of potential between its terminals'to balance the standard. It would, however, ho necfttssary to express-this addedreshit&nee in terms of tW length, of the slide-wire , (by -Hfleiin.'* method, or proportion;. T?his latter method 1 tried and-obtained the balance, hut the ftiiruituriw in^raafjr in t?acli .Was b«loW a- ohm*, objection in batterv te*ts. '•£» the ordinary • ipetre form' of bridge, in which the win/is generally of (UnnRu silver and shout U mm. diameter,, its rettiaiaiKje would'be evuft lower (about -r'i ohm). On the other hand, I find (with Mr. l»uruell) that the same method adapted te. any. ordinary resistance box or bridge fbv Mr. Fahiei i* •Very rapit). and reUabfe. ' «t.', H.l>. wmamea. school of Electrical Kng.ne«nx>gvl j, Prince's Street, Hanover htepiartf, W. • Tiis next experiment was to join the ends of the secondary wire, fc, *, I. In the first experiment the secondary wire'had been idle, , but in thi-t werond experiment everything .remained th« same an in " f\g, 1, the Wirt' Vving imt and ihf. end* yf (he, ttemdetry wife jawed tf'.-.v, y iw!f.,r. On running, the dynamo iwwafTOO the MaXint. lamps Were agal«*brilliantly i«('andf*s<'cht, and WJ itttroduvimj ike'tw* ikfj icrre hut very ttitjhlty reduced in hrilliamy. Evidently thy joining.of the Meeoiidary wire terminals hail a jpowerful effect,'as was shown to be the ease upon breaking the teeandarij tireutt when the Maxim Limp* hreame. -.i dull mi, firing no light,'anA thu« by merely making the secondary circuit' I could turn up the light to brilliancy, and by breaking the. secondary ofreuit I could turn, iha lights down to a dilM red. ' : , • ' : * This experiment shows v cry clearly the action of secondary gone-1 . ratvrs, and beautifully illustrate* the fat t that secondary generator* }mm a ..counter E.M.F. set op in.' their primary circuit, and (hat the vtK/Hdnry\ ainrni.< gem-rated in tht tevond&ni ui/t >:.f ttieh 4fHtmto,-i in their turn Mulr«?i*& lht-t emmter tl.M.F. Xow th<-*> ]ihinomena indicaU; a vast objection or. rather, obst;M:k.» .in tho way of tho distribution, of trie lights bv aecondaw generators, be.mine, although tbe main cufrent'is beyond the reach of Use h^nd, or of. any Hwtrtunent, it can ho reduced to nothing or incivused to ii* max tut tun without in any way interfering with the wire* or ceila conveying tt, • Suppoae a w.ries i»| wmn N?condary era torn hi surien (fig. '£-, .ri alttTnato dynamo, o, sends ourrent through (Jhe primary wire* »i each generator, and all th>' set-Lmdnry win's to be open circuit; in this cajcthe counter E.M.F. would be ao great that very little cur. .rent would paxa through the eeries. Now join up, a

t generator.' Secondary CSeneratOT*. • Hartng aonaj experience in working a system of my own for producing Tights ha vatuo by roean« of neoondary c«rret,t», 1 hlunddwiah .' to notioo a* tew;interesting eiperimanta' whi^.h go far to show the ewmomy, or non-economy, of such currents appUsd to lighting; h shalt^ iherefore, simply describe the- experit&eBte, the result* speak tot •&emMl

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r*sV In th« firat case I u.sed'a'SiemeiiS sltornat* current dysiamo, s>, \u 1, with ita exciter. This was cou^ed tip direct through ten or twejve Maxim, t

t- ta>it|t«, and through a large induetien mil i, so ihut '• all tho eurtwiit • pawed fir^;througtj

: ibalamp* thm through the .prkn*ry wire at the iuductldH eotl. ' ' * :•:'. Thbt induction eoilhad, a Jiwyable cora, arid when the dynamo was sikrted and the current turned on for the first experiment, the core was out of the coil altogether, • The Maxim lamp) 'c*r* then brilliantly imtstieietnt, l^ie apeed of ih« dynatna w»* new taken aad feuud to .he jo*? wr.-pwiaia, .* • ,' Now the core of-the coil Wiminserted gradttally isto'She mil,, and as inore and nn>re of the tor?- entered the coil the ir)eand<(»c«m«e of.th* Maxim lamps iWame k-w and lesw until ftnaHy/«-Sp« the taiv ums in ttt ph>-r, the Mitri,*

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"ymy m tight «( ail; yet the dynamo-*t.t!l. ran'at JCW }«v minute. . ' • -• : - '0ie hisertion of the core, evidently aet up » cooater K.M.F, iu the E.M'.F. of tho dynarao, and. thus reduced tht* enrrent. For this reawm tt in impowtbie to phtain' a current 'from an alternate cuTrent dynamb through large electro-magnet*. I coupled »p this alternate - current dynamo to. tho field-tnagnets of a large dynamo, and although the alternate current dynamo wer powerfully excit«d and running at 800 revolutions per minute, the currant which it could produce • through the field-magnet coils' (the 'total resistance of which was under 2-5.-ohittsi) was too small to 1« measured. Thia is all wt H-lnown j«rh ip* but it. dtK'M pot «•< in to be remembered sometimes in d'enl.rac'with alternate current?. However, we - may asttert that a counter JE,&f.P. is se€ Tip in a coil;of wire carrying " •• ttn'-alternato current and woand upon an irep core, aad this E.M.F. 18 proportionate to the size.of the iron core and, the length .of wire in 'tj*e«il Ktirrcrtuiding the ootB,; ' .' . : -, &r, -Hopkt'nsoTa proposes torcgulate the strength of alternate eur- rents tW thia mean's. . He taier a. GVamate ring_ VUh a very Urge core and arranges the ends of the aecttona of wire so that he cab introduce more or reBS of, it into the. circuit, Evitlently. reguiathin could bt?.<ibtained'by«lhling.*eoro out or into acoti of wire m'cirem't, 'line, great 'advantage such jnothoda of regulation have, ovei ¡¿¡1 other* - -th'y de not u-a*feenergy. V , FIC;t. . I .' U^eJ W-o-oi *-<sc- Wc* ^ a & Ln / fi g c ^ nc.2. aaeoudary wire, so that the induced current goes through and lights,"' *ay, three Swan lamps, the enmjut in the whole circuit will 'be increased, because the counter JS.M.F. due to thegi»nerater, a; will be neutralised by the secondary current bow Sowing, iu ii* i^ndarj- . • • Vow join up the seeoodary teireuit hf * .through three Swan lamp*, the current hi • the' whole primary eireuit will again be iiicreased, beeause the counter E.M.F. of ft will-now be neutrslised, sndaovR.. • l^-ery ge^mtc*'*«eooud^iy:eiMuit«i oeing cle«M wouM-aftWrt the current ia all the others, and'thla without any metulile or otAer co«necUou Whatever between the eeycml aextaadary wire* of between the . secondary &ud priniftry wires, - . -In'^arallcl; are, however, the. seooildary getwrator'ia a beautiful wrf-goveming system of distribution ; but" what about tho sUe of epfi4(w't<*i -|or *uch a ay>tt«drf ' Brodigioua! . '. HnilktB Kt*iM&Jt:'

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' * • ::- &ttteiei<m, • 6. ábra. Rankin Kennedy cikke az Electrical Review 1883. június 9-i számában. Ennek az időnek az eltelte után késedelem esetén, egy hónapig, naponta 50 frank büntetés fizetendő. A lefoglalás a szakértők jelentésében felsorolt 18 olyan állomásra terjed ki, amelyeket két sarknélküli zárt magú transzformátorral szereltek fel. Jelen ítéletet a fellebbezők választása szerint, két újságban kell a Societé