Mallory Products for CDE/6325 Digital Way/Indianapolis IN 46278/Phone: (317)275-2285/Fax: (317)275-2293 5
Application Guide
110 21-25 124-149 3/4291/42.5 50,000
130-156 243-292 1 59 1.670 50,000
270-324 378-454 1 239 1.110 33,500
400-480 540-648 1 119 0.833 25,000
590-708 850-1020 1 179 0.556 16,500
1000-1200 1280-1536 1 239 0.417 12,500
115 21-25 108-130 3/4291/42.5 50,000
124-149 189-227 1 59 1.670 50,000
216-259 340-408 1 89 1.110 33,500
378-454 460-552 1 119 0.833 25,000
540-648 815-978 1 179 0.556 16,500
829-995 1020-1224 1 239 0.417 12,500
125 21-25 81-106 3/4291/42.5 50,000
108-130 145-174 1 59 1.670 50,000
161-193 233-280 1 89 1.110 33,500
243-292 378-454 1 119 0.833 25,000
400-480 590-708 1 179 0.556 16,500
645-774 800-960 1 239 0.417 12,500
165 21-25 88-106 159 1.670 33,500
108-130 124-149 1 89 1.110 33,500
130-156 216-259 1 119 0.833 25,000
233-280 340-408 1 179 0.556 16,500
378-454 590-708 1 239 0.417 12,500
220 21-25 43-52 1 59 1.670 33,500
37-56 72-86 1 89 1.110 33,500
88-106 145-174 1 119 0.833 25,000
161-193 243-292 1 179 0.556 16,500
270-324 430-516 1 239 0.417 12,500
250 21-25 30-36 1 59 1.670 33,500
36-43 64-77 1 89 1.110 33,500
72-86 88-106 1 119 0.833 25,000
108-130 189-227 1 179 0.556 16,500
216-259 324-389 1 239 0.417 12,500
330 21-25 21-25 1 59 1.670 33,500
25-36 30-36 1 89 1.110 33,500
36-43 64-77 1 119 0.833 25,000
72-86 88-106 1 179 0.556 16,500
108-130 130-156 1 239 0.417 12,500
From To
Rated
Voltage Test
Volts AC (rms)
Capacitance
Rating (mfd) Duty Cycle
Secs.
(On) Secs.
(Off)
%
Duty
Cycle
XX
XX
X
(No. of
Starts)
Figure A: Type 2 (MSA)
1.1 VOL TAGE 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 Maximum
Voltage (rms) Cut-Off Voltage (rms)
110 140
115 145
125 160
165 210
220 280
250 300
330 400
These ratings are based on the maximum capacitor temperature
of 150!F.
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.
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.
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.
X X
X X
X T ypical 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 (On) (Off)
Life T est
Duty Cycle %
Duty
Cycle Duration of Test
(Number of Starts)
110 all 3/4291/42.5 75,000
115 all 3/4291/42.5 75,000
125 all 3/4291/42.5 75,000
165 all 1 59 1.670 40,000
220 all 1 59 1.670 40,000
250 all 1 59 1.670 40,000
330 all 1 59 1.670 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.