ELECTROLYTIC
AC MOTOR START CAPACITORS
TYPE MS
HIGH LIGHTS:
Capacitance:
Voltage:
Operating Frequency:
Power Factor:
Ambient Temperature:
Case Sizes:
21 - 1590 Mfd
110 Vac - 330 Vac
50 - 60 Hz
10% Max.
-40gC +65gC
1-
7
/
16
" x 2-
3
/
4
" to
2-
9
/
16
" x 4-
3
/
8
"
FEATURES:
Moisture & Oil Resistant Plastic Case
Compact Size
Easily Mounted
Long Life and High Reliability
APPLICATIONS:
Motor Starting and other
Intermittent AC applications
Made In U.S.A.
The MS motor start aluminum electrolytic
capacitor is used to provide the torque
necessary to start AC motors and can be
used in other intermittent AC applications.
The capacitor comes in all popular styles
with a variety of terminal configuration
choices. NACC Motor Start Capacitors are
designed in accordance with EIA RS-463.
Mallory Products for CDE
6325 Digital Way
Indianapolis, Indiana 46278
Phone: (317) 275-2285
Fax: (317) 275-2293
Internet: http://www.cornell-dubilier.com
Type MS
* NEMA Standard Sizes
Case
Code
D
( 0.015)
Standard Terminal Layouts & Resistor Layout
L
(+0.020, -0.030)
C
(Ref.)
1
/
1
/
1
/
5
/
5
/
7
/
7
/
7
/
2
2
2
8
8
8
8
8
1
*2
3
*4
*5
6
*7
8
1-
7
/
16
1-
7
/
16
1-
7
/
16
1-
13
/
16
1-
13
/
16
2-
1
/
16
2-
1
/
16
2-
9
/
16
(1.4375)
(1.4375)
(1.4375)
(1.8125)
(1.8125)
(2.0625)
(2.0625)
(2.5625)
2-
3
/
4
3-
3
/
8
4-
3
/
8
3-
3
/
8
4-
3
/
8
3-
3
/
8
4-
3
/
8
4-
3
/
8
(2.750)
(3.375)
(4.375)
(3.375)
(4.375)
(3.375)
(4.375)
(4.375)
(.500)
(.500)
(.500)
(.625)
(.625)
(.875)
(.875)
(.875)
Resistors -
Resistors are available at extra cost in
ratings specified. Layout as shown below is manda-
tory on case diameter 1-
7
/
16
" (case # 1-2-3) but other
positioning is possible on larger sizes. ( *Standard)
Rating
Tolerance
Size
(Max)
4700 Ohms 1 Watt
15000 Ohms 1 Watt
5600 Ohms 2 Watt
*15000 Ohms 2 Watt
33000 Ohms 2 Watt
10%
10%
10%
10%
10%
x
3
/
4
1
/
4
x
3
/
4
5
/
16
x
3
/
4
5
/
16
x
3
/
4
5
/
16
x
3
/
4
1
/
4
.140 R
.106 Dia
.385 .285
.160
.250
.094
.109
.070
.365 .281
.154
.250
.094
.109
.250
.094
.365 .281
.154
.1875 Dia
.095 Dia
.406
.266
.130
.156
.100 Dia
.100 Dia
.070
.333
.250
.100 Dia
Solder Lug Terminals
(SL)
(All Cases)
.125
(Ref)
C
Single Disconnect Terminals
(SQC)
(All Cases)
C
Standard
Dual Disconnect Terminals
(DQC)
(All Cases)
C
Dual Disconnect Terminals
W/Solder Lug Terminal
(DQCS)
(Case 4, 5, 6, 7 & 8 only)
C
L
.0625
(Ref)
.0625
(Ref)
.0625
(Ref)
D
Part Number Nomenclature
Standard Part Number
NACC Type Designation
Identifies the basic capacitor design;
MS
A
1
R
10
161
N
Performance
A = EIA Type 2
B = EIA Type 1
Case Code
(See standard ratings page)
Case Type
R = Recessed (Standard).
Voltage Rating
10 = 110
22 = 220
11 = 115
25 = 250
12 = 125
33 = 330
16 = 165
Minimum Capacitance
Expressed in microfarads.
Always 3 or 4 digits.
Resistor
N = No resistor (Standard)
R = With Resistor
2
Mallory Products for CDE/6325 Digital Way/Indianapolis IN 46278/Phone: (317)275-2285/Fax: (317)275-2293
Ratings Charts
MSA Standard Ratings
MFD
21-25
25-30
30-36
36-43
43-52
47-56
53-64
64-77
72-87
88-106
108-130
124-149
130-156
145-174
161-193
189-227
216-260
233-280
243-292
270-324
324-389
340-408
378-455
400-480
430-516
460-552
540-648
590-708
645-774
708-850
720-864
800-960
815-978
829-995
850-1020
900-1080
1000-1200
1020-224
1175-1410
1280-1536
1326-1590
110 Vac
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
2
2 or 3
2 or 3
2 or 3
3 or 4
3 or 4
3 or 4
3 or 4
3 or 4
5
5
7
5,6 or 7
7
7
5,6 or 7
8
7 or 8
7 or 8
8
7 or 8
7 or 8
8
8
115 Vac 125 Vac 165 Vac 220 Vac
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
2
2
2
3
3
3 or 4
3 or 4
3 or 4
3 or 4
4 or 5
5
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
2
2
2 or 3
2 or 3
2 or 3
3 or 4
3 or 4
3 or 4
3 or 4
3 or 4
4 or 5
5 or 6
1
1
1
1
1
1
1
1
1
1 or 2
2
2
2 or 3
2 or 3
2 or 3
2 or 3
3
3 or 4
3 or 4
3 or 4
4 or 5
5
5,6 or 7
5,6 or 7
5,6,7 or 8
5,6,7 or 8
7 or 8
7 or 8
7 or 8
1
1
1
1
1 or 2
1 or 2
1 or 2
250 Vac 330 Vac
1
1
2
2
2
2
2,3 or 4
1 or 2
1 or 2
1,2,3 or 4
2 or 4
3 or 4
3 or 4
3 or 5
5
5
5,6 or 7
7 or 8
7 or 8
7 or 8
7 or 8
8
8
8
8
8
8
MSB Standard Ratings
MFD
21-25
25-30
30-36
36-43
43-52
47-56
53-64
64-77
72-87
88-106
108-130
124-149
130-156
145-174
161-193
189-227
216-260
233-280
243-292
270-324
324-389
340-408
378-455
400-480
430-516
460-552
540-648
590-708
710-850
815-978
110 Vac
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
2 or 3
2
3 or 4
3 or 4
3 or 4
3 or 5
5
5
5
5
7
7
8
8
115 Vac 125 Vac 165 Vac 220 Vac
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
3 or 4
3 or 4
2 or 4
4
4
5
5
5
5 or 7
7
7
7
7 or 8
8
1
1
1
1
1
1
1
1
1
1
1
1
1 or 2
2
2 or 3
2 or 3
3 or 4
3 or 4
3 or 4
4 or 5
5
5
5
5
7
7
8
1
1
1
1
1
1
1
1
1
1 or 2
2
3 or 4
3 or 4
3 or 4
4
4
5
5
5
5
5
7
8
8
1
1
1
1 or 2
1 or 2
250 Vac 330 Vac
1
1
1 or 2
1 or 2
2,3 or 4
1 or 2
2
3 or 4
3 or 4
4 or 5
5
5
5
5
7
8
Normal Performance (EIA Type 2) Extra Performance (EIA Type 1)
1 or 2 2,3 or 4
2,3 or 4 3 or 4
2,3 or 4
3 or 4
4
5
5
5
7
7 or 8
7 or 8
8
8
8
8
4
4
5
5
7
7 or 8
8
8
8
8
2,3 or 4 2,3 or 4
3 or 4
3 or 4
3 or 4
4
5
5
3,4 or 5
5 or 6
5 or 6
5 or 6
5,6 or 7 5,6 or 7
5,6 or 7
7
7
7 or 8
7 or 8
7 or 8
8
8
8
8
8
8
8
7 or 8
7 or 8
8
8
8
8
8
8
8
8
5,6 or 7 5,6 or 7
7
7 or 8
7 or 8
7 or 8
8
8
7
7 or 8
7 or 8
7 or 8
7 or 8
8
8
8
Capacitance ratings in other case sizes may be available.
Contact NACC Application Engineer for assistance.
Case
Number
Diameter
( 0.015)
Length
(+0.020, -0.030)
1
*2
3
*4
*5
6
*7
8
1-
7
/
16
(1.4375)
1-
7
/
16
(1.4375)
1-
7
/
16
(1.4375)
1-
13
/
16
(1.8125)
1-
13
/
16
(1.8125)
2-
1
/
16
(2.0625)
2-
1
/
16
(2.0625)
2-
9
/
16
(2.5625)
2-
3
/
4
(2.750)
3-
3
/
8
(3.375)
4-
3
/
8
(4.375)
3-
3
/
8
(3.375)
4-
3
/
8
(4.375)
3-
3
/
8
(3.375)
4-
3
/
8
(4.375)
4-
3
/
8
(4.375)
* NEMA Standard Sizes
Mallory Products for CDE/6325 Digital Way/Indianapolis IN 46278/Phone: (317)275-2285/Fax: (317)275-2293
3
Mounting Accessories
HB Bracket
.3125 R
.2188 R
HB brackets are used with PL or PLA end caps. The bracket is
assembled to the motor or any suitable surface by two screws in
line at any convenient position within the center-to-center dimen-
sion (C) shown in the chart.
Material: .042 spring steel with black parkerized finish.
.9375 Space
D
.750
Catalog
EIA
Number Case Code
.094
Dimensions (Ref.)
A
3-
3
/
8
"
4-
1
/
64
"
5-
1
/
64
"
B
1-
11
/
64
"
1-
13
/
16
"
2-
23
/
32
"
C*
7
/
8
"
D
1.258
1-
37
/
64
"
2-
5
/
64
"
1.375
*C
.191 R
HB2
.230
.234
1
2-4-6
3-5-7-8
HB4
HB8
1-
1
/
2
"
1-
25
/
32
"
B
A
.875
1.1875
* Center-to-center dimension.
PL and PLA End Caps
Catalog Number
Wire Hole
Toward Bracket
Wire Hole
Away From Bracket
EIA
Case Code
A
Dimension
PL3
PL6
PL8
PL10
PLA3
PLA6
PLA8
PLA10
1-2-3
4-5
6-7
8
1-
7
/
16
"
1-
13
/
16
"
2-
1
/
16
"
2-
9
/
16
"
.375
.375
When assembling directly to the motor frame, the wires are brought
through the bracket hole and connected to the capacitor termi-
nals. Type PL end cap is then placed in position and the entire
assembly snapped into place. Off-motor mounting is similarly
accomplished except that Type PLA caps should be used to pro-
vide for leads emerging from the opposite side of the cap without
going through the bracket hole.
End caps and brackets are shipped
loose and should be separately
ordered when required. Add 'A'
to the PL part numbers if PLA cap
is desired (Example: PLA3).
A
A
PL
PLA
.176 x .281
(3 places)
A
PLA
PL
VR Brackets
.219
C
A
.375
B
Mtg
120g
Type VR brackets are available for vertical mounting. They are
supplied with clamping screws and nuts.
Material is .035 thick 1010 CRS, commercial grade #4 temper
ASI-scale. Parts are finished with .0001 (nominal) zinc chromate
plating.
Dimensions (Ref.)
2 Holes
.201 Dia
B
Mtg.
C
2 Holes
.1561 Dia.
.156
.500
Catalog
Number
EIA
Case Code
A
1-
3
/
8
" to 1-
7
/
16
"
1-
3
/
4
" to 1-
13
/
16
"
2" to 2-
1
/
16
"
2-
1
/
2
" to 2-
9
/
16
"
B
1-
25
/
32
"
2-
1
/
4
"
2-
1
/
2
"
3"
C
1-
7
/
8
"
2-
9
/
16
"
2-
13
/
16
"
3-
5
/
16
"
.562.750
1.125
.750
VR3
VR6
VR8
VR10
1-2-3
4-5
6-7
8
VR3
Wire Leads
VR6-8-10
Insulated wire leads are available by special order.
Specifications:
Size:
Insulation:
#18 AWG x 10" long
600V ; +105gC
Terminal Configurations:
#10 Ring
1/4" Quick Connect - Female Flag
1/4" Quick Connect - Female In-Line
Bare - Stripped and Tinned
Other options and configurations available upon submission of
customer drawing and/or specification.
4
Mallory Products for CDE/6325 Digital Way/Indianapolis IN 46278/Phone: (317)275-2285/Fax: (317)275-2293
Application Guide
1.1 VOLTAGE RATING
The rated voltage of the capacitor must be greater than or equal to
the average voltage across the capacitor terminals during the mo-
tor starting cycle. This is not necessarily the same as the motor
line voltage. In addition, the cutoff voltage rating of the capaci-
tor must be greater than or equal to the maximum voltage attained
across the terminals of the capacitor in actual service.
The maximum recommended cut-off voltages for the seven stan-
dard voltage ratings are as follows:
Rated
Voltage (rms)
110
115
125
165
220
250
330
of 150gF.
Maximum
Cut-Off Voltage (rms)
140
145
160
210
280
300
400
115
Rated
Voltage Test
Volts AC (rms)
Figure A: Type 2 (MSA)
Capacitance
Rating (mfd)
From
To
Duty Cycle
Secs. Secs.
(On)
(Off)
3
/
4
%
Duty
Cycle
t
(No. of
Starts)
110
125
165
These ratings are based on the maximum capacitor temperature
220
1.2 CAPACITANCE RATING
The capacitance is chosen to give the necessary starting torque to
the motor. The minimum capacitance value is the minimum de-
signed capacitance. The maximum capacitance is 20% more than
that value.
250
330
1.3 DUTY CYCLE
The duty cycle should be calculated for each application. It is the
ratio of the time the capacitor is on voltage to the total time of one
cycle. The duty cycles for the normal performance of Type 2
(MSA) capacitors are listed in Figure A. NACC Type MSA ca-
pacitors may be used in any intermittant application within their
temperature and voltage range where the duty cycle does not ex-
ceed that listed in the table in Figure A. This is in accordance
with the standards in EIA Specification RS-463 for Type 2 ca-
pacitors.
If a particular application exceeds the normal duty cycle, but does
not exceed the values listed in Figure B, an extra performance or
Type 1 (MSB) capacitor is required.
t
21-25
130-156
270-324
400-480
590-708
1000-1200
21-25
124-149
216-259
378-454
540-648
829-995
21-25
108-130
161-193
243-292
400-480
645-774
21-25
108-130
130-156
233-280
378-454
21-25
37-56
88-106
161-193
270-324
21-25
36-43
72-86
108-130
216-259
21-25
25-36
36-43
72-86
108-130
124-149
243-292
378-454
540-648
850-1020
1280-1536
108-130
189-227
340-408
460-552
815-978
1020-1224
81-106
145-174
233-280
378-454
590-708
800-960
88-106
124-149
216-259
340-408
590-708
43-52
72-86
145-174
243-292
430-516
30-36
64-77
88-106
189-227
324-389
21-25
30-36
64-77
88-106
130-156
1
1
1
1
1
3
/
4
1
1
1
1
1
3
/
4
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
29
1
/
4
59
239
119
179
239
29
1
/
4
59
89
119
179
239
29
1
/
4
59
89
119
179
239
59
89
119
179
239
59
89
119
179
239
59
89
119
179
239
59
89
119
179
239
2.5
1.670
1.110
0.833
0.556
0.417
2.5
1.670
1.110
0.833
0.556
0.417
2.5
1.670
1.110
0.833
0.556
0.417
1.670
1.110
0.833
0.556
0.417
1.670
1.110
0.833
0.556
0.417
1.670
1.110
0.833
0.556
0.417
1.670
1.110
0.833
0.556
0.417
50,000
50,000
33,500
25,000
16,500
12,500
50,000
50,000
33,500
25,000
16,500
12,500
50,000
50,000
33,500
25,000
16,500
12,500
33,500
33,500
25,000
16,500
12,500
33,500
33,500
25,000
16,500
12,500
33,500
33,500
25,000
16,500
12,500
33,500
33,500
25,000
16,500
12,500
Typical life expectancy is 50,000 cycles for 110, 115 and 125V
ratings, and 40,000 total cycles for 165, 220, 250 and 330V
ratings. The number of cycles shown in the table above are
for the convenient test time of 35 days total for all ratings. See
section 3.0 for testing procedures.
Figure B: Type 1 (MSB)
Rated
Voltage
AC (rms)
Capacitance
Rating
Life Test
Duty Cycle
(On)
3
/
3
/
3
/
4
4
4
(Off)
%
Duty
Cycle
Duration of Test
(Number of Starts)
1.4 Frequency
These capacitors are engineered for 60 Hz application but may
be operated between 47 Hz and 60 Hz without damage provided
voltage limitations stated above are observed. For other varia-
tions in frequency, contact North American Capacitor Company,
Indianapolis, IN.
110
115
125
165
220
250
330
all
all
all
all
all
all
all
1
1
1
1
29
1
/
4
29
1
/
4
29
1
/
4
59
59
59
59
2.5
2.5
2.5
1.670
1.670
1.670
1.670
75,000
75,000
75,000
40,000
40,000
40,000
40,000
If an application exceeds the duty cycles in Figure B, other
methods of capacitor selection must be used. Contact NACC,
Application Engineering for assistance.
Mallory Products for CDE/6325 Digital Way/Indianapolis IN 46278/Phone: (317)275-2285/Fax: (317)275-2293
5
