design of a 2 hp repulsion start induction motor
TRANSCRIPT
Scholars' Mine Scholars' Mine
Professional Degree Theses Student Theses and Dissertations
1931
Design of a 2 HP Repulsion Start Induction motor Design of a 2 HP Repulsion Start Induction motor
Joseph Worley
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Recommended Citation Recommended Citation Worley, Joseph, "Design of a 2 HP Repulsion Start Induction motor" (1931). Professional Degree Theses. 113. https://scholarsmine.mst.edu/professional_theses/113
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by
Joseph ~Vorley
A
T Ii E SIS
submi tted to the f acul ty of th e
SClI GOL OF ~.'TIlJE S .AlTD l:~fE TAI~LURGY
OF TIl]}; lJ1JIVERSITY O:B" IvTISSOURI
in partial fuJ. fillmen t of the vlork require d fo~r the
D E G R E E 0 F
ELECTRICAL EI:~GIIJ'EER
Rolla, 1~o.
1931
Approved by ~....."" _"_. ...../1-..-.. "_...~__(Jl;~,'d4an.......~".."""~""..-"';~~..../_"__"" "" -
P~otessor of Electrical Engineering.
Table o~ Contents.
Introduction .•••••••••••••••••••••••••••••••• l
Required Data •••••••••••••••••••••••••••••••• 2
Stator Wlndlgg••••••••••••••••.•••••••••••• ~.3
Stator Magnetic Circuit ••••••••••••••••••••••4
Rotor Winding ••••••••••••••••••••••••••••••••6
Rotor Magnetic Circuit •••••••••••••••••••.•••?
Required Ampere Turns •••••••••••••••••••••••• 7
Magnetizing Current ••••••••••••••••••••••••••8
No Load Losses ••••••••••••••••••••••••••••••• 9-10-11
No Load Current •••••••••••••••••••••••••••••• ll~12
Reaotance ••••••••••••••••••••••••••••••••••• :12
Blooked Current •••••••••••••••••••••••.•••••• 13
Blocked Power Factor•••••••••••••••••••••••••14
MaximlJIll rrr> ••••••••••••••••••••••••••••••••••• 14
Circle Diagram Discussion•••••••••••••••••••• 14-15
Per~ormance Data Compar1son •••••••••••••••••• 16
Final Tests on Motor••••••••••••••••••••••••• l?-18-19
INDEX
..... ...............
Ampere turns total •••••••••••••••••Air Gap w••••••••••••••••••••••••••
Rotor Teeth ••••••••••••••.•••Rotor yoke ••••••••••••••••••Stator Teeth •••••.stator yoke •••••••••••••••••••••••
8?88?7
• • • •
........... ................................... ............ ...
28261310767
Armature Diagram of Connections ••••.Punching••••••••••••••••••••••••••'Reactano e •••Res i stan ce •••••Teeth••••Winding•••••••••••••••••••••Yoke ••••••••••••••••••••••••••••••
BearingCommutator Cover••••••••••••••••••Drawings ••••••••••••••••••••••••••Friction••••••••••••••••••••••••••Loss ••••••••••••••••••••••••••••••Pulley cover••••••••••••••••••••••
2929-30101030
Brake Test ••••• • • • • • • • • • • • • • • • • • • • • • 18...19
Loss .
............................Brush Drawing.Friction •••• • • • • • • • • • • • • • •
321111
Circle Diagram•••••••••••••••••••••• 14-15
Commutator Drawing •••••••••••••••••• 31
Core Loss Curve ' 24
Current Blocked ••••••••••••••••••••• 13Full Load ••••••••••••••••••••••••• 3No· Load ••••••••••••••••••••••••••• 12
Data••••••••••••••••••• ~ •••••••••••• 2
Distribution·Curve •.••••••••••••••••• 22
Erficiency - Full Load ••••••••.•••••• 2-3-17-18
Field Connections •.••••••••••••••••• 27Pun ching ••• ,' • • • • • • • • • • • • • • • • • • • • •• 25Resistano.e •••••••••••••••••••••••• 10Wind ing • • • • • • • • • • • • • • • • • • • • • • • • • •• 4
...............
• • •Iron Losses
Rotor TeethRot or Yoke •••Stator Teeth •••.••••••sta tor Yoke ••
·..·...........111199
823
·......t~agnet iza t ion Current' •••Curve •••••••••••••••••••••••••••
Perrormance Curve .................. 21
14312• • •
·......• • • • • • • •
Power Factor Blocked •••••••••••••••Full Load ••••••••••No Load •••••••
Punching Armature ••••••••••Fi eld •••••••••••••••••••••••••••
'2625
Reactance ArmatureFi aId •••••••••••••••
·...... ·..,1312
34-35
1010
1011261310?6
....·....
·....·.............
• • • • • • • • • • •
..........
·...
..............
....
...
..............
Resistance Armature ••••••••••••••••Field •••••••••••••
Rotor Copper Losses •••Iron Lo sse s •••••••••••••Punching ••Reactance ••••••••••••••••••••••••Resistance •••••••••Teeth ••Winding ••.••••••
Section and End View
Shaft Drawing •••••••••••••••••••••• 33
109261210
4-;-644
18-19.•
.....................
......... ~ .............
• • • • • • • • • • • • • • • • • • • • • • • • • •
....................' .B.rakeTest
Stator Copper Losses •••••••••••••••Iron Losses ••••••••••••••••••••••Punching •••••••••••••••••••••••••ReactanceResistance •••••••••••••••••••••••TeethWinding ••••••••••••••••••••••••••Yoke
.............List of Illustrati ons.
eircle diagram•••••••••••••••• • •• 20
Performance.Diagram••••••••••••••••••••••••••• 21
Distribution Curve •••••••••••••••••••••••••••• 22
Magnetization Curve •••• • • • • • • • • • • • • • • • • • • • •••• 23
Core Loss Curve •••••••••••••••••••••••••••• ~ •• 24
Field Punching . ...................• •••• 25
Armature Punching••••••••••••••••••••••••••••• 26
Field Diagram of Connecti ens ••'•••••••••••••••• 27
Armature Diagram of Connectiont ••••••••••••••• 28
Commutator Cover •• • • • • • • • • • • •••••• 29
Bearing for Pulley cover••••••••••••••••••••••30
Comm.ut a tor •••••.••••.•••.•••..••.••••••.•...•• 31
·Bnlsh••••••••••••••••••••••••••••••••••••••••• 32
Sha ft ••••••••••••••••••••••••••••••••• .- ••••••• 33
Seotion••••••••••••••••••••••••••••••••••••••• 34
End Views ••••••••••••••••••••••••••••••••••••• 35
-1-
The Repulsion start Induction motor comprises
a vJound fi eld or sta tor of lamina ted s true t11re and
a wound armature or rotor whose coils are connected
to a commutator upon v.rhich brushes bear and function
during the starting period.
This motor opertites as a repulsion motor during
the starting period and at a 9redetermined speed the
short circuiting device actuates and short circuits
the commutator. The motor then op-erates as an induc
tion or squirrel cage type.
The starting -torque of this type motor is excei>t
ionally high, generally 300% to 400% of full load
torqueo Consequently this type of motor is regarded
as ha ving a high efficien oy a t s tart. The starting
current is low which causes very little line distur
bance. Due -to this charaoteristic, this motor is rec
ommended :for general use by the -Central Stations.
Due to the high starting torque oharaotistios,
thi s motor is well adapted forap-pliea tions suoh as
- air compressors, baker's maohinery, ooncrete mixers
and refrigeration service.
-2-
Design o'f a 2 HP Repulsion Start Induction Ivlotor.
Required -
Q,uiet Operati on
Efficiency 75% at rated load.
Power Factor ??% at rated load.
starting Torque not less than 350%.
~jaximum - 4 HP
40°C Rise by Thermometer on Armature.
~Jo tor Da ta •
110/220 volt, 60 cycle operation. 1725 R.P.M.
Diameter of stator punchings 9.750"
stator slots based on s~acing of 32.
Connections, ,2 oircuits, 2 poles in·series. :I
4 poles series for 220 volt and series-
parallel for 110 volt operation •
.Numb.er of rotor slots - 48
~lumber of bars in commu ta tor - 48
Axial .vVid th 4.000" over end fibre.
Rotor Twis ted 1-1/2 slots.
Single Air Gap .020 ft•
rz-t,)-
E LEe T RIC ~ L
ElTATOR Vv'IJ.<TDIl.JG
The a pproximate fl ux per "901e for a 2 lIP
motor wh,ich is to have a 4 HP maxirnum is 390,000
line.s, ·
pole is"..)
Then the number of turns required per.795 =Dist. Faotor.95 • Voltage Drop Factor
N:;: 55 x 108 x .954.44 x 60 x .795 x 390,000
63 turns per pole.
Since the efficiency desi red is 75% the
total watts input will be,
746 x 2• 75
1990 watts •
The power factor required is 77% which
make s it po ssi b le to find the full load ell rrent ,
which is,
1990220 x .77
11.72 anperes
In order to keep the heating at a minimum
an allowance of 550 circular mils per ampere should
be made. The proper size of wire for the stator 1s
550 x 11.72 = 6460 Cir. Mils.
This is ap~proximately #1'2 Enamel and't,
cotton wire.
-4-
The stator winding is 63 #12 E&C per
pole, or distributed' properly and using 2 #15 E&C
which can be handled wi th greater ease, the vlinding
becomes - tor the inside, middle. and outside coils
It is necessarjr at this point to consider
the calculation of the stator magnetic circuit.
MAG NET ICC IRe U I TeA Leu L A T ION
STATOR YOKE.
Assume a working density of· 68,500 lines
per square inch. Then the thickness of the s ta tor
yoke will be,
STATOR TEETH
Assume a density of 78,500 lines per
square inch and since the teeth are to have a
taper the minimum thioknessof the teeth will be -
390,000 x 1.57 .95 == .260"8 x 78,500 x 3.93?HX
A oheck should: be made at this time to
determine if' there. is space available in stator.'
punehirtg. for ·the?Jinding. However, we find· it nec-
. essc.;ry to determine the d1~me ter Qf the rotor or bore'
·of the s .tat6:r_. Should an' under ·size annature be
-5-
chosen excessive heatirlg will result. In some design~; tlle
D2L or a. ctive TrE. terial of the rotor iE~ the determining
factor. I-Iov;ever , it is possible to determine directl~r the
proper eize by calculating the flux density in the air
gap. By setting a limit to this value, it is possible to
quickly determine the bore of the stator. In most designs
i t is good ':)ractice to allovi 30,000 lines "!jer square inch
as density in the air gap.
Conse(J.llently, "h'e get the pole -ni tC.h in this case
390 z000 x 1.57 x •95 = 4.94"3.93?"x 30,000
From this we get the bore of the statorit
D = 4.94 x 4 =: 6.30 tt
'~'3 .1416Rather than to use an odd size such as this, we select
6 .250 ft as th e b or e •
Ache ck sho uld be made a t this time to determine if
there is available space irl the field for the winding.
required.
2 x 24 x .6512
55 .368 Square inch area
In order to keep the tooth tip vibration at a
minimum, a thickness of .075" .is alIa_do The thiokness
of the tooth tip at the side of the slot is .-125".
The slot depth is
9.750'" - (2 x .760")::: 8.230".
6.250" + (.2 x .125 ft)::: 6.500 tt
1.7~Oft
1.730"2
-6-
= .865" slot depth
.3680: .427" average width of slot
.865 11
4271'1 :t .050'·
.050#is allowed as slot taper.
The maximum tooth width is
8.230" x 3.141632 .... 477" = .329n
The minimum tooth width is -
6.500" :x 3.141632 - .377" = .260"
The above value of .260" agrees with the value
as previously caloulated. Consequently we have
ample slot capacity.
ROTOR\VINDING.
In designing rour pole 60 cycle Repulsion
Induction Motors., the writer has always tried to use
in the rotor approximately the same slot~turns as in
the field and at the same time keeping in mind t,he
cross secti on of' the copper.
In this case we will use #16 E&C wire in the rotor.
The number of turns per slot in the rotor are -
21 x 6 x4 x ~260 x2 .= 26.648 x 2580
Since we are using a 48 slot rotor with a 48 bar
commutator the rotor winding is 13-26 116 E&C.
-7-
1.'1' .d. G· 1>T IE TIC C' IRe 1J I T C .,:',~ 1.1 C 1J L J.::" T I 0 J>J S---_..-..-...-.-,...-..- ~--~ ............. ~_-..-...-- ....... --~--. .. _------
ROTOli TEETII
Assuming a density in the rotor teeth of 83,500 lines
per square inch, we find the ~idtr of the rotor teeth to
be
.1551/390,000 x 1.57 x .95
83,500 X 3.937#x .95 x 12
The flux density in the yoke of the rotor is
390,000 x .95 34 200 1- -2~1.45}'x 3.937/1x .95 == ., lnes "'1er sq. In.
O.h.Le l1IJATI O~l OF IJill?ERE TtJIiIJS RECiU'IRJBD.
ST.li~eOR YOKE.
From the magnetization curve
68,500 lines per sq. in.::: 4 amp. turns/inch.
(9.?50 f1 - .760 ft) x 3.1416
- 4 ::: ? .82'" length of path
? .8211X 4 = 31.28 ampere turns.
ST.i:..TOR TEETH.
FroTa tb.e magne ti za ti on curve
78,500 lines per 5(1. in. ~ 6.25 amp. turns/'inch •
• 989 tf X 2 = 1.978" length of path
I.978 ft X 6.25" =12.32 ampere turns
AIR GAP.
el.6 x ~O,OOO x .020Hx 2.54 x 1.210. 6.45
::: 459.00 ampere turns.
-8-
ROTOR TEETH
From the magneti za ti011 curve
83,500 lines/sq. in. :::= 8.75 amp. turns/in •
• 94511
X 2 = 1.89 on length of -pa th
8.75 X 1.890ft~ 16.53 ampere turns
From the magnetization curve
34,300 lines/sq.• in. ~- 1.25 arap turns/in.
1.560 n + 2.150'" ~: 3.710 tt length of path.
. II.1.25 x 3.710 :::: 4.63 ampere turns.
The total ampere turns reql1ired for the various
parts of the magnetic circuit are:
Stator Yoke 31.28
stator Teeth 12.32
Air Gap ~ 459 .00
Rotor Teeth =- 16.53
Rotor Yoke ~ 4.63
523.16
~il~ it G lJ E .T I Z I N G C IT R R E 1~ T·~--_.-~--....-,-- --_ ..... __ .-.. ....
I 'T ~ · 2 (523 • ? 6 ) -h 1.8 x .79 x 252 2. 92 amperes
allowing 95% for ero 55 flux current. The magnetizing
current is -
2.92 x 1.95= 5.70 amperes Mag. Current.
-9-
CALCULATIOl\T OF NO Ii..QAD LOSSES
STATOR IRON LOSSES
STATOR YOKE.
The volume of the yoke expressed in kg is
4.87~- 4.114 2 x 3.1416 x 3.93?"x .95 x 16.4 x 7.9000
10.43 kilo grams.
The density of the yoke expressed in lines per
sq. em is -
68,500 = 10620 lines/sq. em.6.45
From the core loss curve we find the corresponding
loss to be 3.25 watts per kg. The loss in the yoke 1s
10.43 x 3.25 = 33.9 watts.
STATOR TEETH
The volume of the stator teeth expressed in
kilograms is -
4 x 6 x .284 X 3.937'IX 16.4 x 7.9 x • 98g/l x .95
1000 +
3.1416 (4.1142 - 3.1252 x 3._ 9371'X' 16.4 x 7.9 x .954 000
I:X
6 • 00 ki lograms.,
, The density of the teeth expressed in lines per
sq. em 1s -
785006.45
=12180:. lines/sq. em..
From the core loss curve 'we find the corresponding
loss to be 4.68 watts per kilogram. The loss in the te$th
is -
4.68 x 6 = 28.08 watts.
-10-
COPPER LOSSES
STATOR VlINDIT,JG RESISTANCE.
RF~ 1.20 x 1.16 x 8.00'/X 2.54 X 2 x 252.
5700 x 3.304
= .753 Ohms at 40° c.ROTOR '~lI:r-IDING RFSISTM{CE.
R = 17J/x 48 x 4.48 x 13 3.97 Ohms.A 12· x 1000 =
R1
= 3.~7 .X 2522:A
• 8452 x 6242 = .908 Ohms •
The copper 10s5 in the stator is
5.702 x .753 =~ Watts.
The copper loss in the rotor is -
2 ~5270~2 x .90S = 14.7 watts.
LOSSES---. - ..... .-. - ~
BEARING LOSSES.
The commutator cover bearing loss in watts ts
1.20 {.S75"x 2.125~ (1750 x 3.1416 X.S75'1 3/ 2 ..( 12 x 1000 )
17.9 watts.
The pulley cover bearing loss in watts is -
1.20 (1,,062"x 2.125'~ (1750 ;3.1416 x 1.062'13/; 28.7
( 12x 1000 )
The total bearing loss ·in watts is 46.6 •.
As it is difficult to determine the windage losses,
10% 1s added to the bearing loss which makes total frio, ....
tional and windage 1085.51.2 watts.
-11-
The brush friction loss may be expressed in
the following:-
1.2:5 eX 4 (1 X .281j X 3.1416 :x: 4.062":x: 17~O100 X 12
= 26.2 Watts.
SUMrYtARY OF LOSSES AT NO LOAD.
Since the rotor runs a practically synchron-
ous speed it is assumed that the rotor iron losses are
negligible. There are add! tional losses which occur at the
surface of the stator teeth and further losses due to
eddy currents. It is generally assumed that these are·
approximately 75% of the stator iron losses.
Losses in Stator Yoke 33.90
Losses in Sta tor Teeth 28.08
75% Additional 46.30
Stator Copper Losses 24.50
Rotor Copper losses 14.70
Friction and Windage 51.20
Friction due to Brushes 26.20
Total No Load Watts224.88
NO LOAD CURRENT.
The component of the current due to the
losses is ....
224 •.88220
= 1.02 Amperes.
-12-
This current should be added ~vecto~ally" to
the magnetizing current in order to determine the no load
current.
I == V 5,.70~ + i.02! = 5.78 Amperes,
No Load Po.wer,'Factor=225 x 100 = 17.68%220 x 5.78
CAL C U L it T 1. 0 N' ·0 F REA eTA N Q E.
STATOR
= 2.095 ems.
The permeance, of the path of the stator slot
leakage flux per em. of the slot is -
~¥ ,~ 'J. 1P 1 25 .818 ..... 047 ,.. 2 x .05'0 + .075
S = • 3 x • '4101,' .377" • 377" + .110" :rIO
The leakage flux per em,. length of end wire
is -
Pw = .46 x 3 ~lOg1/
1.5 x 4.50 ) x 2 x 1.30 a .825 Oms.3.97/~ )
.945 ems.=
Expressed in terms of motor width 1 t 1s
.825 :x: 4.5011
3.937"
The pe~eaaoe' due to the slot opening is -
.= 2.245 ems.
The total pe~.aD8.: 1s 5.285 ems for the stator.
The reaotance 'for the stator expressed in ohms is
12.5 x 60 x 2522 X 3.937h x 2.54 x 5.2852 :x: 6 x lOB
2.125 Ohms.
=
ROTOR
The pennea.c. of the path of the rotor slot
leakage flux per Qm of the slot 1s-
-13-
~.714'/ .064// - .04?" 1/ ~+ .060 x 2 .060 2
3 X .155H 3 X .096"T .235#+ .235t.o9cf .090
= '7.44 Cms.
The permeance due to the end wire of an~·armature
is generally .8 em for this case we get -IIP .8 x 4.50
E = 3.93711 = .92 ems.
The permeance due to connections at the
conmutator is so small too t it can be neglected.
The leakage flux due to the slot opening in the
rotor expressed in ems is -
plo = 1.25 (.504" - .o9d1 :::: 3.45 Oms.( 6 x .025")
The total permeanCe for the rotor is 11.81 ems
The reactanoe of the rotor expressed in terms of the stator
is -
12.56 x 60 x 2522 X 3.93?HX 2.54 x. 8.09 x .792 X.952
. 2 x 12 x 108 x .8452
= 1.84 Ohms.
The total reactance is 2.125 + 1.84 = 3.965 Ohms
The total impedance when the commutator is short
cirelli ted and the rotor is at a stand-still 1s -
The bloekedeurrent for the above condi tiona
will be -
2204.30
= 51.2 Amper.es
-14-
The power factor blocked will be -
1. 661 100 _ 38 8(/r4.30 x -. 70
TIle v.ora ttE~ input to the rna tor for t:he locked
and, shorted COmTIllltator c()ndition are
= 4320 ,VEt tts.
IIavin;;.~ determinod the n.o loa dcurrent and
power factor and the blocked current and ~o~er factor,
it is ~;ossible to construct the circle diagram arld check
the mEtximum liP vlhich tIle motoT* ,rill develop. From tl.1is
diagrarnit is possible to'deterr:lil1e tb,e power f8.ctor
and efficiency for full load.
T11ewriter Ilas found tb.at it is possible to
approximate the nlaximum HI' vlhich the motor t8 capable
of developing by usin.e~ the va.lues heretofore calculated
in tI:Le folloVJing ma11Iler.
~vIax. :HP = 220 (51.2 - 5.78) .85 =: 4.11 HP2 (1 + .388) ?46
The circle diagrCTIl is constructed in the 11sual
manner., Using the angJ_e whose cosine is the no load
po\ver factor, the an'g]_eAOC is laid off and the no load
curren t· .A.O is measured. according 'to a sui table scale. The
angle COB oorrespondsto thepovJer factor angle 'for blooked
condition. The blocked current is measured on the lineOB.
-15-
Through point A and parallel to the horizontal, the line
AD is drawn. The line AE represents the no load watts.
Through points A and B and using a point on the line AD,
the circle is drawn. Since we know the resistance of the
rotor and stator it is possible to separate the losses for
blocked condition. The losses corresponding to any load
can then be determined for the stator and rotor. The max-
imum HP which the motor will develop occurs where a line
parallel t·o AB is tangent to the circle. The maximum
power factor which the motor will have can be found by
, drawing a tangent to the circle through point O. By locat
Ingthe point corresponding to the rated load, it 1s possible
to determine the effi 01 ency and power factor.
It was found that the circle diagram varies
with the frame co'nstruction and the amount of twist either
in the rotor or stator • Consequently, for th·e larger frames
such as has been used in the design of recent motors, an
approximate calculation has been used. Since the results
are within 2% of actual t es t value, the writer chooses to
use the following: -
3.950 HP=Max. Hi? = 16.3 (1 ~ '.1992) 225, 146
It 1s realized that this 1s not ~hsolutely
oorrect and further work and tests are continuing to
determine if it is possible to const~uet the el'rcle diag
'ram so that the results will agree wi th the test data.
-16-
The wri tar has designed during recent years,
Repulsion Start Induotion and Polyphase motors ranging
from 1/8 HI? to 2 HP., for frequencies ranging from 25 to
60 cycles.
In the design of single-phase induction motors
rated from 1/30 liT' to 1/2 HI? , the problem of sound condi
tion has resulted in extensive noise tests. The writer
remembers particularly an instance where it was round
that 32 slots in the stator and 41 slots in the rotor
result ed in an exoellent sound condi tion. Thi 8 combinat,lon
was tried in a smaller and a larger motor in an effort to
improve the noise condition. It was foundtha. t noisy
operation resulted. There:rore sound not only is dependent
upon the combine. tion but also upon the size and shape of
the frame. or course in making the aboTe ,statement, it
is assumed that the various portions of the magnetic
01 rcui t are approximately the proper 51 ze and shape.
-10....
Performanoe Data Comparison
Predetermined - Actual Brake Test
5.78 5.75
225 a36
17.68 18.65
2.00 2.025
11.60 11.20
1965 aooo?6.0 'l5.5
77.0 81.1
81.9 62.7
3,.95 & 4.11 4.00
I:~o Load
Current
Watts
Power ]'ao tor %
Full Load
Amperes
Watts
Efficiency %
Power Factor %
Maximum Pf. %
Maximum H.P.
Locked Rotor With
Commutator Shorted
Watts
Amperes
Power Factor %
4320
51.20
38.80
4120
49~6
3?7
The starting torque of the final motor 1s 409~ ot the
full load torque whioh should be ample starting torque
for almost any eondi.tion.
-18-
B,rake. Test
Type IR9 AB-130-?440 H.P •. 2 Date 8...5-30.
Volts 110/220 Phase 1 Cyol.es 60
Field 'tVinding 18-21.. 23 (2 # l5) E&C
Field Iron 9724 A Field Bore 6.252"
Arm. Winding 13 - 26 #16 E&C
Arm. Iron 6248-A Diameter 6.,.21l!'
Arm. Twist 1-1/2 Slots Uomnlutator 48 Bars.
INDUCTION TEST
Watts Volts Amps. RI?M· wt. Arm. H.P. Eff.% Pf.%
4700 220 29.5 1625 10 15i 3,.99 63.5 72.4
4100 220 24.0 1675 10 14i 3.85 70.0 77.8
3275 220 18.0 1730 8 l5 3.30 '75.1 sa.7
2000 220 11.2 1760 5 14i 2.03 75.5 SI.!
1560 220 g.45 17'15 4 14 1.58 75.5 75.0
1100 22,,0 7.65 1785 4 9 1.04 69.0 66.0
660 220 6.45 1790 2 9 .512 57.7 46.6
236 220 5.75 1795 No· Load 18.65
3400: 220 32.8 Lift 16 18t
BRUP 10 12
-19-
REPULSION' TEST
Watts Vo~ts Amp. liPM l-vt. Arm., H.P.
2680 220 14.6 1030 10 16 2.61
3040 220 16.? 955 10 lsi 2.81
3280 220 18.0 900 10 20 2.86
3680 22-0 19.8 850 12 19 3.0?
I\4AGNETIZATION TEST
watts Volts Amp.
400: 300 9.19
320 260 7.10
240 220' 5,.78
20Q ~80 4.57
155 140 3.51
120 100 2.68
110 70 2.30
BEAT RUN
Rise 0 c.
Frame 2·7.5
Field Iron 31.5
Arm. Iron 40.0
Joseph Worley/Louise Beiser~