106:
694:
29:
118:
268:
385:
PCB containing capacitors must be replaced and disposed by consulting local environmental authorities. If these capacitors leak or fail, PCBs can be released into the environment and will very likely result in extremely expensive environmental cleanups, and potentially, lawsuits. There are extensive
202:
If a wrong capacitance value is installed, it will cause an uneven magnetic field around the rotor. This causes the rotor to hesitate at the uneven spots, resulting in irregular rotation, especially under load. This hesitation can cause the motor to become noisy, increase energy consumption, cause
129:
Start capacitors briefly increase motor starting torque and allow a motor to be cycled on and off rapidly. A start capacitor stays in the circuit long enough to rapidly bring the motor up to a predetermined speed, which is usually about 75% of the full speed, and is then taken out of the circuit,
175:
is broken. If the switch is always open, the start capacitor is not part of the circuit, so the motor does not start. If the switch is always closed, the start capacitor is always in the circuit, so the motor windings will likely burn out. If a motor does not start, the capacitor is far more
382:(PCBs). These are extremely toxic and persistent chemicals with many long-lasting negative human and wildlife health effects. Capacitors were required to be labeled in the U.S. with "No PCBs" or similar language. Capacitors without these labels are suspect.
238:μF, and also on the voltage. A 440-volt capacitor can be used in place of a 370-volt, but not a 370-volt in place of a 440-volt. The capacitance must remain within 5% of its original value. Round cylinder-shaped dual run capacitors are commonly used for
325:
to leak out. Some capacitors have a "pressure-sensitive interrupter" design that causes them to fail before internal pressures can cause serious injury. One such design causes the top of the capacitor to expand and break internal wiring.
320:
A faulty run capacitor often becomes swollen, with the sides or ends bowed or bulged out further than usual; it can then be clear to see that the capacitor has failed, because it is swollen or even blown apart causing the capacitor's
254:(μF). Older capacitors may be labeled with the obsolete terms "mfd" or "MFD", which can be ambiguous but are, especially in this context, used for microfarad as well (a millifarad is 1000 microfarads and not usually seen on motors).
242:, to help in the starting of the compressor and the condenser fan motor. An oval dual run capacitor could be used instead of a round capacitor; in either case the mounting strap needs to fit the shape used.
199:(historically: metallised paper capacitors) and are energized the entire time the motor is running. Run capacitors are rated in a range of 1.5 to 100 μF, with volt classifications of 250, 370 and 440 V.
215:
supports two electric motors, with both a fan motor and a compressor motor. It saves space by combining two physical capacitors into one case. The dual capacitor has three terminals, labeled
586:
329:
Over many years of use the capacitance of the capacitor drops; this is known as a "weak capacitor". As a result, the motor may fail to start or to run at full power.
97:
compressor units, to boost both the fan and compressor motors. Permanent-split capacitor (PSC) motors use a motor capacitor that is not disconnected from the motor.
332:
When a motor is running during a lightning strike on the power grid, the run capacitor may be damaged or weakened by a voltage spike, thus requiring replacement.
822:
723:
109:
Simple capacitor-start single-phase motor circuit diagram. Note that starting capacitor is connected in series with auxiliary winding just like in
454:
188:
require a "run capacitor" to energize the second-phase winding (auxiliary coil) to create a rotating magnetic field while the motor is running.
517:
191:
Run capacitors are designed for continuous duty while the motor is powered, which is why electrolytic capacitors are avoided, and low-loss
792:
647:
335:
573:
593:
367:
531:
739:
541:
493:
234:
Dual capacitors come in a variety of sizes, depending on the capacitance (measured in microfarads, μF), such as 40 plus 5
643:"CPSC, Firms Announce Recall of Infinity and Lifestyle Spas" U.S. CPSC, Washington, DC, CPSC.gov, 2003-12-09, webpage:
370:(CPSC) has received more than 100 reports of incidents of overheating of the motor capacitor, with some fires started.
763:
307:
715:
285:
289:
228:
777:
666:"Identification, Management, and Proper Disposal of PCB-Containing Electrical Equipment used in Mines"
458:
390:
has much information on the correct way to test and manage these toxic chemicals in older capacitors.
797:
665:
379:
168:
with non solid electrolyte and therefore they are only applicable for the short motor starting time.
105:
793:
http://electronics.stackexchange.com/questions/101408/what-is-the-purpose-of-the-motor-run-capacitor
812:
728:
421:
719:
278:
165:
134:
that releases at that speed. Afterward the motor works more efficiently with a run capacitor.
644:
561:
8:
817:
704:
782:
338:/EN 60252-1 2011 specifies the following levels of protection for motor run capacitors:
708:
511:
185:
172:
131:
743:
537:
499:
489:
192:
122:
58:
to create a rotating magnetic field. There are two common types of motor capacitors,
617:
732:
239:
787:
651:
94:
78:
55:
20:
196:
503:
366:
circulating pump can overheat if defective. This poses a fire hazard, and the
806:
483:
49:
322:
251:
28:
292: in this section. Unsourced material may be challenged and removed.
110:
90:
572:
This link only shows irrelevant types (July 2018) do they even exist?
41:
267:
387:
117:
93:
heat furnaces for example. A "dual run capacitor" is used in some
74:
52:
45:
798:
https://www.epa.gov/sites/production/files/documents/pcbidmgmt.pdf
778:
http://highperformancehvac.com/run-start-capacitors-hvac-motors-1/
363:
86:
82:
618:"MotorCap DM AC Film Capacitors for Motor Run Applications"
726:
and tools are available to assist in formatting, such as
574:
386:
toxicological reports on PCBs in the research community.
378:
Motor capacitors manufactured before 1978 likely contain
562:
Motor start and motor run capacitors; capacitorguide.com
783:
http://www.capacitorformotor.com/motor_capacitor.html
195:are used. Run capacitors are mostly polypropylene
804:
141:μF, with four major voltage classifications: 125
452:
203:performance to drop and the motor to overheat.
788:http://www.wikihow.com/Check-a-Start-Capacitor
422:"Capacitor Sizing Dilemmas (motor capacitors)"
137:Start capacitors usually have ratings above 70
419:
707:, which are uninformative and vulnerable to
362:A motor capacitor which is a component of a
345:S1, S2 – fail open-circuit or short-circuit;
16:Electrical capacitor used in electric motors
722:and maintains a consistent citation style.
823:Heating, ventilation, and air conditioning
587:"AC Capacitors for Motor Run Applications"
557:
555:
553:
516:: CS1 maint: location missing publisher (
764:Learn how and when to remove this message
308:Learn how and when to remove this message
584:
488:(3rd ed. rev. and expanded ed.). .
448:
446:
444:
442:
440:
438:
250:The units of capacitance are labeled in
171:The motor will not work properly if the
116:
104:
89:spa pumps, powered gates, large fans or
27:
550:
415:
413:
411:
409:
407:
405:
403:
368:U.S. Consumer Product Safety Commission
44:that alters the current to one or more
805:
206:
164:μF are always non-polarized aluminium
121:Capacitor motor with a speed limiting
663:
481:
457:. justtherightair.com. Archived from
435:
687:
673:U.S. Environmental Protection Agency
639:
637:
477:
475:
400:
290:adding citations to reliable sources
261:
176:likely the problem than the switch.
714:Please consider converting them to
100:
13:
14:
834:
683:
634:
472:
179:
692:
485:Energy-efficient electric motors
352:
266:
257:
657:
592:. GE Capacitors. Archived from
277:needs additional citations for
77:that are in turn used to drive
73:Motor capacitors are used with
32:A typical motor start capacitor
718:to ensure the article remains
610:
578:
566:
536:. Firewall Media. 2024-02-19.
524:
229:hermetically-sealed compressor
1:
393:
533:Alternating Current Machines
453:JustTheRightAir (Sep 2008).
348:S3 – fail open-circuit only.
75:single-phase electric motors
7:
623:. Epcos AC, Munich, Germany
455:"Round Dual Run Capacitors"
245:
10:
839:
18:
380:polychlorinated biphenyls
160:Start capacitors above 20
373:
19:Not to be confused with
357:
166:electrolytic capacitors
126:
114:
33:
120:
108:
31:
286:improve this article
482:Emadi, Ali (2018).
420:LA.gov, Louisiana.
342:S0 – no protection;
207:Dual run capacitors
53:alternating-current
650:2013-01-08 at the
213:dual run capacitor
193:polymer capacitors
186:AC electric motors
184:Some single-phase
173:centrifugal switch
132:centrifugal switch
127:
115:
68:dual run capacitor
34:
774:
773:
766:
724:Several templates
543:978-81-7008-222-4
495:978-1-4200-3081-5
318:
317:
310:
40:is an electrical
830:
769:
762:
758:
755:
749:
747:
736:
696:
695:
688:
677:
676:
670:
661:
655:
641:
632:
631:
629:
628:
622:
614:
608:
607:
605:
604:
598:
591:
582:
576:
570:
564:
559:
548:
547:
528:
522:
521:
515:
507:
479:
470:
469:
467:
466:
450:
433:
432:
430:
429:
417:
313:
306:
302:
299:
293:
270:
262:
240:air conditioning
237:
163:
156:
152:
148:
144:
140:
101:Start capacitors
79:air conditioners
838:
837:
833:
832:
831:
829:
828:
827:
813:Electric motors
803:
802:
770:
759:
753:
750:
738:
727:
713:
697:
693:
686:
681:
680:
668:
662:
658:
652:Wayback Machine
642:
635:
626:
624:
620:
616:
615:
611:
602:
600:
596:
589:
583:
579:
571:
567:
560:
551:
544:
530:
529:
525:
509:
508:
496:
480:
473:
464:
462:
451:
436:
427:
425:
418:
401:
396:
376:
360:
355:
314:
303:
297:
294:
283:
271:
260:
248:
235:
209:
197:film capacitors
182:
161:
154:
150:
146:
142:
138:
123:governor device
103:
95:air conditioner
60:start capacitor
56:induction motor
38:motor capacitor
24:
21:Punch capacitor
17:
12:
11:
5:
836:
826:
825:
820:
815:
801:
800:
795:
790:
785:
780:
772:
771:
716:full citations
700:
698:
691:
685:
684:External links
682:
679:
678:
656:
633:
609:
585:Regal-Beloit.
577:
565:
549:
542:
523:
494:
471:
434:
398:
397:
395:
392:
375:
372:
359:
356:
354:
351:
350:
349:
346:
343:
316:
315:
274:
272:
265:
259:
256:
247:
244:
208:
205:
181:
180:Run capacitors
178:
102:
99:
15:
9:
6:
4:
3:
2:
835:
824:
821:
819:
816:
814:
811:
810:
808:
799:
796:
794:
791:
789:
786:
784:
781:
779:
776:
775:
768:
765:
757:
745:
744:documentation
741:
734:
733:documentation
730:
725:
721:
717:
712:
710:
706:
701:This article
699:
690:
689:
674:
667:
660:
653:
649:
646:
640:
638:
619:
613:
599:on 2011-10-26
595:
588:
581:
575:
569:
563:
558:
556:
554:
545:
539:
535:
534:
527:
519:
513:
505:
501:
497:
491:
487:
486:
478:
476:
461:on 2008-07-12
460:
456:
449:
447:
445:
443:
441:
439:
423:
416:
414:
412:
410:
408:
406:
404:
399:
391:
389:
383:
381:
371:
369:
365:
353:Safety issues
347:
344:
341:
340:
339:
337:
333:
330:
327:
324:
312:
309:
301:
298:December 2019
291:
287:
281:
280:
275:This section
273:
269:
264:
263:
258:Failure modes
255:
253:
243:
241:
232:
230:
226:
222:
218:
214:
204:
200:
198:
194:
189:
187:
177:
174:
169:
167:
158:
135:
133:
124:
119:
112:
107:
98:
96:
92:
88:
84:
80:
76:
71:
69:
66:(including a
65:
64:run capacitor
61:
57:
54:
51:
47:
43:
39:
30:
26:
22:
760:
751:
740:Citation bot
702:
672:
659:
625:. Retrieved
612:
601:. Retrieved
594:the original
580:
568:
532:
526:
484:
463:. Retrieved
459:the original
426:. Retrieved
384:
377:
361:
334:
331:
328:
319:
304:
295:
284:Please help
279:verification
276:
249:
233:
224:
220:
219:for common,
216:
212:
210:
201:
190:
183:
170:
159:
136:
128:
72:
67:
63:
59:
50:single-phase
37:
35:
25:
664:Dan Bench.
323:electrolyte
252:microfarads
130:often by a
818:Capacitors
807:Categories
754:April 2023
720:verifiable
627:2012-04-22
603:2011-09-04
504:1083013923
465:2008-09-24
428:2012-01-29
394:References
153:V, and 330
111:LC circuit
91:forced-air
705:bare URLs
512:cite book
42:capacitor
709:link rot
648:Archived
424:. LA.gov
388:U.S. EPA
246:Labeling
46:windings
364:hot tub
87:jacuzzi
83:hot tub
729:reFill
540:
502:
492:
236:
223:, and
162:
155:
151:
149:V, 250
147:
145:V, 165
143:
139:
703:uses
669:(PDF)
621:(PDF)
597:(PDF)
590:(PDF)
374:Toxic
48:of a
737:and
538:ISBN
518:link
500:OCLC
490:ISBN
358:Heat
227:for
225:HERM
70:).
62:and
645:CP7
336:IEC
288:by
221:FAN
157:V.
809::
671:.
636:^
552:^
514:}}
510:{{
498:.
474:^
437:^
402:^
231:.
211:A
81:,
36:A
767:)
761:(
756:)
752:(
748:.
746:)
742:(
735:)
731:(
711:.
675:.
654:.
630:.
606:.
546:.
520:)
506:.
468:.
431:.
311:)
305:(
300:)
296:(
282:.
217:C
125:.
113:.
85:/
23:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
