ALTERNATING GENERATORS AND SYNCHRONOUS MOTORS. 159 
297%. 
In Par. 283, the weight of armature copper is 885 lbs. 
BE SE. ARG: pe Oa 4s 4 stampings is 5,860 ‘‘ 
Ear Tearin sees" ‘<  ** field copper is 3,200 °° 
Against these values, the standard type of alternator shows 
much lower material weights, the total amount of copper 
DEMERS A, CRU Pht bck Oi eR eV Kala ae obo we 1,500 Ibs. 
while the armature stampings only amount to 3,750 Ibs. 
It may be pointed out, that the weight of the iron could 
have been reduced by decreasing the height of the arma- 
ture core. 
Weights of Low Speed Alternator.—A comparison 
is not possible between the castings and auxiliary parts, 
as in the present ease the flywheel weight is placed in the 
magnet wheel; therefore it is preferable to give a detailed 
list of material for a low speed alternator as an example. 
The armature consists of : 
Cast iron shell and shield rings.......... 12,880 pounds 
BEMMMDMEE CMLOMDINGS 5 oo. 6 lk ee le ee ws we a,380) °° 
TATETALIS oo ere'S nv ala eleicale dee 8 we ot, ad 
0) ee 896 ‘* 
micanite insulation and hard wood fixing 
TS SSSR, els eae. eer ae i. ans 
terminal board, brush gear and name plate 1,120 ‘‘ 
lg date aa oe SS, ED aR) on ep Suerte - * 
The magnet wheel consists of : 
Cast iron flywheel (rim, hub and arms)... 32,480 pounds 
MINING: 5 6 eddie se Wis eee soe ee ee 3,584 ‘* 
bolts and steel wedges for fixing the poles. 2,128 ‘ 
SS IGS 2 aa 3,000 ** 
wrought iron and press board magnet 
bobbins and brass end plates for the 
CT ye a RRS ao) Ea a 392; - ** 
gun metal slip rings and cast iron bracket. $92.- ‘°* 
REE RAL) Ae Yaa 42.9%€ © ** 
