Mfd Capacitor
 |
 GE Genteq Capacitor Dual Run Round 35 5 uf MFD 370 Volt VAC Z97F9834 97F9834 $22.99 Time Remaining: 14d 2h 42m Buy It Now for only: $22.99 |
 York Armstrong Capacitor 125 MFD 370V NEW $1.99 Time Remaining: 1h 13m |
 GE Genteq Capacitor Dual Run Round 45 5 uf MFD 370 Volt VAC Z97F9895 97F9895 $22.90 Time Remaining: 11d 10h Buy It Now for only: $22.90 |
 GE Capacitor Oval 10 uf MFD 370 volt Z97F9002 97F9002 $10.90 Time Remaining: 8d 10h 25m Buy It Now for only: $10.90 |
 Mars Mars2 Capacitor 70 5 uf MFD 440 volt 12823 12255 $21.99 Time Remaining: 19d 4h 4m Buy It Now for only: $21.99 |
 GE Genteq Oval Run Capacitor 75 uf MFD 370 volt vac 50 60 hz CAP010753O $10.99 Time Remaining: 14d 11h 15m Buy It Now for only: $10.99 |
 35 + 5 MFD 440V ROUND RUN CAPACITOR PRCFD355 HVAC $9.95 Time Remaining: 17d 12h 30m Buy It Now for only: $9.95 |
 Dual Run Motor Capacitors 440 VAC Round select MFD ratings Microfarad options $14.95 Time Remaining: 7d 18h 23m Buy It Now for only: $14.95 |
 53 64 MFD 220 VAC Capacitor for Sears Opener 30B0363 $12.99 Time Remaining: 26d 11h 4m Buy It Now for only: $12.99 |
 45 + 5 MFD 440V ROUND RUN CAPACITOR PRCFD455 HVAC $9.95 Time Remaining: 28d 15h 56m Buy It Now for only: $9.95 |
 40 + 5 MFD 370V ROUND RUN CAPACITOR PRCD405 HVAC $9.95 Time Remaining: 25d 14h 10m Buy It Now for only: $9.95 |
 40 + 5 MFD 440V ROUND RUN CAPACITOR PRCFD405 HVAC $9.95 Time Remaining: 20d 5h 7m Buy It Now for only: $9.95 |
 Goodman Amana Janitrol Capacitor 60 5 uf MFD 370 volt VAC CAP050600370RTS $32.99 Time Remaining: 24d 10h 31m Buy It Now for only: $32.99 |
 50 + 5 MFD 440V ROUND RUN CAPACITOR PRCFD505 HVAC $11.95 Time Remaining: 17d 12h 47m Buy It Now for only: $11.95 |
 15 20 25 30 35 40 45 50 55 60 80 MFD Run Capacitor Round 440V NEW $19.99 Time Remaining: 24d 20h 44m Buy It Now for only: $19.99 |
 DUAL CAPACITOR 5 35 MFD 370V 50 60Hz Oval NIB $18.99 Time Remaining: 5d 11h 43m Buy It Now for only: $18.99 |
 GE Genteq 35 5 uf Mfd 440 volt Round Motor Run Capacitor 97F9848 $20.40 Time Remaining: 15d 7h 50m Buy It Now for only: $20.40 |
 75 MFD 370 VAC OVAL MOTOR RUN CAPACITOR POC75 HVAC $2.95 Time Remaining: 26d 6h 7m Buy It Now for only: $2.95 |
 GE Genteq Oval Run Capacitor 10 uf MFD 370 volt vac 50 60 hz CAP011003O $10.99 Time Remaining: 14d 11h 19m Buy It Now for only: $10.99 |
 Oval Run Capacitor 10 uf mfd 370 VAC GE Genteq 97F9002 Replaces P291 1003 $10.95 Time Remaining: 26d 3h 4m Buy It Now for only: $10.95 |
 50 MFD 370 VAC ROUND RUN CAPACITOR PRC50 PACKARD NEW $8.25 Time Remaining: 29d 12h 41m Buy It Now for only: $8.25 |
 Mallory 53 64 MFD 220VAV Capacitor LifmasterCraftsman and many others $9.99 Time Remaining: 2d 14h 22m |
 Lennox Armstrong Ducane Capacitor 45 75 uf MFD 440 volt 69M67 67M6701 Dual Run $31.99 Time Remaining: 29d 7h 57m Buy It Now for only: $31.99 |
 GE Genteq Capacitor Dual Run Round 45 5 uf MFD 370 Volt VAC 27L568 97F9895BX $22.90 Time Remaining: 7d 2h 44m Buy It Now for only: $22.90 |
 Janitrol Goodman Capacitor 45 5 uf 370 volt vac B9457 7200 Amana MFD Dual Run $28.99 Time Remaining: 29d 7h 30m Buy It Now for only: $28.99 |
 Run Capacitor Round 35 5 uf Mfd 440 Volt HVAC R $14.90 Time Remaining: 19d 13h 21m Buy It Now for only: $14.90 |
 45 + 5 MFD 370V ROUND RUN CAPACITOR PRCD455 HVAC $9.95 Time Remaining: 9d 9h 41m Buy It Now for only: $9.95 |
 Mars Mars2 Run Capacitor 35+5 uf MFD 370 volt 12766 $14.99 Time Remaining: 9h 3m Buy It Now for only: $14.99 |
 30 MFD 370 VAC ROUND RUN CAPACITOR PRC30 PACKARD NEW $5.50 Time Remaining: 29d 11h 42m Buy It Now for only: $5.50 |
 25 MFD 370 VAC ROUND RUN CAPACITOR PRC25 PACKARD NEW $4.95 Time Remaining: 29d 12h 27m Buy It Now for only: $4.95 |
 GE Genteq Capacitor Dual Run Round 35 5 uf MFD 370 Volt VAC 97F9834BZ2 $22.99 Time Remaining: 8d 12h 7m Buy It Now for only: $22.99 |
 GE Genteq 50 75 uf Mfd 370 volt Round Motor Run Capacitor 97F9971 $23.20 Time Remaining: 15d 7h 20m Buy It Now for only: $23.20 |
 NIB Motor Run Capacitor 40+5 uf MFD 370 440 volt Blower $9.99 Time Remaining: 14d 3h 13m Buy It Now for only: $9.99 |
 Motor Start Capacitor 710 850 MFD 165 VAC MARS 11082 $19.99 Time Remaining: 16d 10h 15m Buy It Now for only: $19.99 |
 GENTEQ 10 MFD 370 VAC OVAL MOTOR RUN CAPACITOR 97F9002 POC10G HVAC $6.95 Time Remaining: 28d 6h 6m Buy It Now for only: $6.95 |
 Mars Mars2 Round Run Capacitor 30 uf MFD 370 volt 12217 $12.99 Time Remaining: 15d 5h 5m Buy It Now for only: $12.99 |
 Rheem Start Capacitor 43 17075 04 88 106 MFD uf 330 VAC $14.99 Time Remaining: 24d 11h 43m Buy It Now for only: $14.99 |
 Janitrol Goodman Capacitor 35 5 uf 370 volt B9457 5300 Amana Dual Run MFD VAC $27.99 Time Remaining: 1d 5h 14m Buy It Now for only: $27.99 |
 OEM DiversiTech Motor Round Run Capacitor 25 uF MFD 370V Volt VAC 37250R 50 60HZ $11.99 Time Remaining: 6d 2h 39m Buy It Now for only: $11.99 |
 Motor Start Capacitor 72 88 MFD 330 VAC MARS2 11961 $11.49 Time Remaining: 25d 5h 21m Buy It Now for only: $11.49 |
 NIB Round Dual Run Capacitor 40 + 5 Mfd x 440 VAC $9.95 Time Remaining: 6h 48m Buy It Now for only: $9.95 |
 Mars2 Run Capacitor 30 5 uf MFD 370 volt 12764 round $10.00 Time Remaining: 6d 15h 49m Buy It Now for only: $14.00 |
 York Luxaire Coleman 15 uf MFD Capacitor 024 25900 000 $9.99 Time Remaining: 16d 11h 3m Buy It Now for only: $9.99 |
 Mars Mars2 Round Run Capacitor 50 uf MFD 370 volt 12725 $17.99 Time Remaining: 1d 11h 53m Buy It Now for only: $17.99 |
 Liftmaster 30B532 Motor Capacitor 53 64 MFD Garage $18.99 Time Remaining: 19d 2h 41m Buy It Now for only: $18.99 |
 55 + 5 MFD 440V ROUND RUN CAPACITOR PRCFD555 HVAC $11.95 Time Remaining: 17d 12h 55m Buy It Now for only: $11.95 |
 GE Capacitor D Run Round 80 5 uf MFD 370 volt 27L651BZ3 $31.50 Time Remaining: 3d 4h 7m Buy It Now for only: $31.50 |
 Motor Start Capacitor 145 175 MFD 110 125VAC MARS 11013 $9.99 Time Remaining: 6d 7h 50m Buy It Now for only: $9.99 |
 GE Genteq Oval Run Capacitor 5 uf MFD 370 volt vac five CAP010503O $10.99 Time Remaining: 14d 9h 20m Buy It Now for only: $10.99 |
 370 VAC Oval Blower Fan Motor Capacitor 5 uf MFD Free Shipping $5.96 Time Remaining: 28d 1h 44m Buy It Now for only: $5.96 |
 Trane Start Capacitor CPT00091 135 162 uf MFD 330 VOLT with Resistor $38.30 Time Remaining: 11d 6h 29m Buy It Now for only: $38.30 |
 GE Genteq 55 5 uf Mfd 370 volt Round Motor Run Capacitor 97F9815 $23.80 Time Remaining: 15d 7h 11m Buy It Now for only: $23.80 |
 GE Genteq Oval Run Capacitor 125 uf MFD 370 volt vac 50 60 hz CAP011253O $12.99 Time Remaining: 14d 11h 36m Buy It Now for only: $12.99 |
 GE Capacitor Round 50 5 uf 440 volt Z97F9850 97F9850 Dual Run VAC MFD $26.99 Time Remaining: 23d 11h 36m Buy It Now for only: $26.99 |
 GE GENTEQ Capacitor Oval 75 uf MFD 440 volt 97F9036BZ3 $12.99 Time Remaining: 14h 14m Buy It Now for only: $12.99 |
 GE Capacitor Round 80 5 uf MFD 370 volt 27L323 27L651 $31.50 Time Remaining: 26d 10h 11m Buy It Now for only: $31.50 |
 35 + 5 MFD 370V ROUND RUN CAPACITOR PRCD355 HVAC $8.95 Time Remaining: 25d 13h 34m Buy It Now for only: $8.95 |
 Motor Dual Run Capacitor 60+5 uf MFD 370 440 Volt $12.99 Time Remaining: 29d 8h 22m Buy It Now for only: $12.99 |
 GE Capacitor Oval 75 uf MFD 370 volt Z97F9001 97F9001 $11.99 Time Remaining: 2d 12h 27m Buy It Now for only: $11.99 |
 GE Genteq 30 5 uf Mfd 370 volt Round Motor Run Capacitor 27L877 $17.45 Time Remaining: 15d 8h 8m Buy It Now for only: $17.45 |
 GE Capacitor Round 25 5 uf MFD 370 volt 97F9803 $14.99 Time Remaining: 17d 6h 6m Buy It Now for only: $14.99 |
 12794 Motor Run Capacitor 60+50 MFD 440VAC Round $12.00 Time Remaining: 6d 15h 49m Buy It Now for only: $16.00 |
 Rheem Start Capacitor 43 17075 10 145 175 MFD uf 250VAC $28.99 Time Remaining: 5d 7h 46m Buy It Now for only: $28.99 |
 Motor Start Capacitor 56 72 MFD 110 125VAC MARS 11007 $9.99 Time Remaining: 6d 7h 38m Buy It Now for only: $9.99 |
 GE Capacitor Round 30 uf MFD 370 volt Z97F9608 97F960 $12.99 Time Remaining: 5d 10h 1m Buy It Now for only: $12.99 |
 Motor Run Capacitor 30+5 uf MFD 370 440 volt Blower $6.90 Time Remaining: 2d 7h 48m Buy It Now for only: $6.90 |
 Mars Mars2 Run Capacitor 35+5 uf MFD 370 volt 12266 $17.99 Time Remaining: 18d 9h 38m Buy It Now for only: $17.99 |
 Motor Start Capacitor 88 108 MFD 165 VAC MARS 11076 $10.99 Time Remaining: 13d 11h 6m Buy It Now for only: $10.99 |
 GENTEQ 75 MFD 370 VAC OVAL MOTOR RUN CAPACITOR 27L566 POC75G HVAC $6.95 Time Remaining: 28d 5h 59m Buy It Now for only: $6.95 |
 Oval Motor Capacitor 7 uf MFD 330 vac Volt Fan Blower 005 2954 MF Made in USA $10.99 Time Remaining: 6d 10h 38m Buy It Now for only: $10.99 |
 Mars Mars2 Round Run Capacitor 25 uf MFD 370 volt 12715 $11.99 Time Remaining: 15d 4h 57m Buy It Now for only: $11.99 |
 Mars Mars2 Run Capacitor 60+5 uf MFD 440 volt 12294 $22.99 Time Remaining: 18d 9h 57m Buy It Now for only: $22.99 |
 Mars Mars2 Oval Run Capacitor 75 uf MFD 370 volt 12907 $6.99 Time Remaining: 1d 4h 18m Buy It Now for only: $6.99 |
 GE Capacitor Oval 75 uf MFD 370 volt 27L566 27L566BZ3 $11.99 Time Remaining: 4d 9h 14m Buy It Now for only: $11.99 |
 60 MFD 370 VAC ROUND RUN CAPACITOR PRC60 PACKARD NEW $9.50 Time Remaining: 26d 6h 23m Buy It Now for only: $9.50 |
 Lennox Armstrong Ducane Dual Run Capacitor 25 5 uf MFD 440 Volt 15N37 15N3701 $18.99 Time Remaining: 28d 11h 4m Buy It Now for only: $18.99 |
 55 + 5 MFD 370V ROUND RUN CAPACITOR PRCD555 HVAC $10.95 Time Remaining: 26d 7h Buy It Now for only: $10.95 |
 5 MFD 370 VAC OVAL MOTOR RUN CAPACITOR POC5 HVAC $2.49 Time Remaining: 22d 23h 54m Buy It Now for only: $2.49 |
 80 + 5 MFD 370V ROUND RUN CAPACITOR PRCD805 HVAC $16.95 Time Remaining: 26d 7h 7m Buy It Now for only: $16.95 |
 Motor Start Capacitor 189 227 MFD 165 VAC MARS2 11934 $10.99 Time Remaining: 24d 10h 8m Buy It Now for only: $10.99 |
 Mars Mars2 Run Capacitor 25+5 uf MFD 370 volt 12261 $17.99 Time Remaining: 18d 9h 22m Buy It Now for only: $17.99 |
 HVAC Motor Run Capacitor 55 5 uf MFD 440V $14.00 Time Remaining: 6d 15h 50m Buy It Now for only: $20.00 |
 Mars Mars2 Run Capacitor 50 5 uf MFD 370 volt 12755 $17.99 Time Remaining: 15d 7h 59m Buy It Now for only: $17.99 |
 10 MFD 370 VAC OVAL MOTOR RUN CAPACITOR POC10 HVAC $3.49 Time Remaining: 19d 5h 34m Buy It Now for only: $3.49 |
 Mars Mars2 Round Run Capacitor 35 uf MFD 370 volt 12718 $12.99 Time Remaining: 15d 5h 4m Buy It Now for only: $12.99 |
 OEM DiversiTech Motor Dual Run Capacitor 5 50 uF MFD 440V Volt VAC 4JR0550 $19.99 Time Remaining: 1d 4h 49m Buy It Now for only: $19.99 |
 70 + 5 MFD 370V ROUND RUN CAPACITOR PRCD705 HVAC $16.95 Time Remaining: 26d 7h 49m Buy It Now for only: $16.95 |
 Carrier Bryant 40 5 uf MFD 370 Volt Capacitor HC93CA041 $23.99 Time Remaining: 25d 17h 32m Buy It Now for only: $23.99 |
 Mars Mars2 Run Capacitor 45+5 uf MFD 370 volt 12269 $18.99 Time Remaining: 17d 10h 22m Buy It Now for only: $18.99 |
 30 + 5 MFD 440V ROUND RUN CAPACITOR PRCFD305 HVAC $8.95 Time Remaining: 17d 13h 4m Buy It Now for only: $8.95 |
 20 MFD 440 VAC ROUND RUN CAPACITOR PRCF20 PACKARD NEW $5.35 Time Remaining: 29d 12h 48m Buy It Now for only: $5.35 |
 30 + 5 MFD 370V ROUND RUN CAPACITOR PRCD305 HVAC $8.95 Time Remaining: 25d 15h 51m Buy It Now for only: $8.95 |
 ICP Heil Tempstar Dual Run Capacitor 40 3 uf MFD 440 Volt 1086680 HQ1086680AX $37.99 Time Remaining: 2d 8h 3m Buy It Now for only: $37.99 |
 Sears Craftsman 53 64 MFD Garage Door Opener Capacitor $7.00 Time Remaining: 3d 6h 2m Buy It Now for only: $7.00 |
 NIB Dual Run Capacitor 35 5 uf MFD 440 volt Motor Fan $17.99 Time Remaining: 10d 10h 41m Buy It Now for only: $17.99 |
 GE Genteq Capacitor Round 40 4 uf MFD 440 volt 27L549 $34.99 Time Remaining: 23d 5h 51m Buy It Now for only: $34.99 |
 OEM DiversiTech Motor Oval Run Capacitor 10 uF MFD 440V Volt VAC 45100H 50 60HZ $10.99 Time Remaining: 1d 9h 34m Buy It Now for only: $10.99 |
 NIB Dual Motor Run Capacitor 45 5 uf MFD 370 440 volt $18.99 Time Remaining: 14d 3h 13m Buy It Now for only: $18.99 |
 Motor Start Capacitor 56 70 MFD 220 250 VAC MARS2 11943 $11.99 Time Remaining: 24d 10h 33m Buy It Now for only: $11.99 |
 Capacitor 5 uf mfd 370 VAC GE Genteq 27L570 27L570BZ3 97F5705 Z97F5705 $6.55 Time Remaining: 1d 2h 25m Buy It Now for only: $6.55 |
Mfd Capacitor
What is the work way of Motor run Capacitor ?
Capacitor is a device for storing an electrical charge.In a way, a capacitor is a little like a battery. Although they work in completely different ways, capacitors and batteries both store electrical energy. If you have read how batteries work, then you know that a battery has two terminals. Inside the battery, chemical reactions produce electrons on one terminal and absorb electrons at the other terminal. A capacitor is a much simpler device, and it cannot produce new electrons — it only stores them. A capacitor consists two metal plates insulated from each other. When opened, the inside looks like two sheets of foil with wax paper in between them and rolled tight, similar to a roll of paper towel. Years ago the oil filled type used PCB's as a coolant. Today most capacitors are the dry type.
Capacitors are charged with electricity, then releases its stored energy at a rate of sixty times per second in a 60 cycle alternating current system.The sizing is critical to motor efficiency just as sizing of batteries is critical to a radio. For example, a radio that requires a 9V battery will not work with a 1.5V size battery. Thus, as the battery becomes weaker the radio will not play properly. A motor that requires a 7.5 mfd capacitor will not work with a 4.0 mfd capacitor. Much the same way, a motor will not run properly with a weak capacitor. This is not to imply bigger is better, because a capacitor that is too large can cause energy consumption to rise. In both instances, be it too large or too small, the life of the motor will be shortened due to overheated motor windings. Motor manufacturers spend many hours testing motor and capacitor combinations to arrive at the most efficient combination. There is a maximum of +10% tolerance in microfarad rating on replacement start capacitors, but exact run capacitors must be replaced. Voltage rating must always be the same or greater than original capacitor whether it is a start or run capacitor. Always consult manufacturers to verify correct capacitor size for the particular application.
There are two basic types which are used in electric motor :
1)Run capacitorsare rated in a range of 3-70 microfarad (mfd).Run capacitorsare also rated by voltage classification. The voltage classifications are 370V and 440V. Capacitors with ratings above 70 microfarad (mfd) are starting capacitors.Run capacitorsare designed for continuous duty, and are energized the entire time the motor is running. Single phase electric motors need a capacitor to energize a second phase winding. This is why sizing is so critical. If the wrong run capacitor is installed, the motor will not have an even magnetic field. This will cause the rotor to hesitate at those spots that are uneven. This hesitation will cause the motor to become noisy, increase energy consumption, cause performance to drop, and cause the motor to overheat.
Themotor run capacitorsusually have two styles. one is metallized polypropylene AC / motor-run capacitors which are used in most of the older equipment. Large round metal cans. The other ismetallized polypropylene film capacitorsthat are much smaller and come with a mounting tab that can be screwed anywhere on the frame. of the unit. Both types offer the exact same qualities and electrical characteristics. Most important is to get the exact electrical ratings for the capacitor and then the case style.
2) Starting capacitors are housed in a black plastic case and have a mfd range as opposed to a specific mfd rating on run capacitors. Start capacitors (ratings of 70 microfared or higher) have three voltage classifications: 125V, 250V, and 330V. Examples would be a 35 mfd at 370V run capacitor and an 88-108 mfd at 250V start capacitor. Start capacitors increase motor starting torque and allow a motor to be cycled on and off rapidly. Start capacitors are designed for momentary use. Start capacitors stay energized long enough to rapidly bring the motor to 3/4 of full speed and are then taken out of the circuit.
Introduction of Motor
An electric motor is basically composed of windings around a magnet. Motors are either multi-phase or single-phase. Multi-phase motors generate starting torque along the various windings by applying out of phase voltages to each winding in a pattern that generates a torque force in the desired direction. Single-phase motors must generate the same starting torque however they have only one phase to work from. This means they have to have a method to generate a shifted version of the single phase voltage to send to one of their windings.
There are three common methods of creating single-phase electric motors: capacitor start, split-phase, and shaded pole. Each other these motors has some method to provide starting torque to the motor by shifting the voltage given to one of the windings on the motor by some angle. This phase shift corresponds to one winding of the motor having a voltage before another coil. The difference in time between when one coil has a voltage and when a second coil has a voltage causes the torque force and begins the movement of the motor.
To start to solve why capacitive start motors work we can generalize Ohm's Law, V = IR, and say that V = IZ where Z is a generalized impedance. The impedance is composed of an the inductance, capacitance, and resistance. Inductance will cause the current to lag the voltage, capacitance will cause the current to lead the voltage, and resistance has no effect on the timing between the current and voltage.
The Function of The Start and Run Capacitor used for Motors
Most smaller, single phase motors usually have a permanent magnet armature that is pushed or pulled around by the rotating inductive field produced by the stator (outside) windings. The inductive field rotates simply as a result of the positive or negative alternations of the 60HZ AC current flowing through the windings. The problem is that when the voltage is applied, the 60HZ is applied immediately, the rotation of the field through the windings begins immediately, and the armature has no chance to react (or catch up, as it were) to the field.
The start Capacitor provides that electrical "push" to get the motor rotation started. It does this by creating a current to voltage lag in the seperate start windings of the motor. Since this current builds up slower, the armature has time to react to the rotating field as it builds up, and to begin rotating with the field. Once the motor is very close to it's rated speed, a centrifugal switch disconnects the start cap and start windings from the circuit. Watching a single phase motor starting you can see that this all happens very quickly.
Without a start Capacitor(such as when one burns up) when the voltage is applied, the motor will just sit and hum. But if you were to grab the shaft and give it a spin, the motor would start and run normally.The run capacitor and aux. windings never drop out of the circuit in a cap-start, cap-run motor. The current to voltage lag is always present, which makes the motor act like a two phase motor. The advantage of a cap-start, cap-run motor over a cap-start, induction-run motor is that cap-run motors operate at a higher power factor than induction-run. Single cap-start / run motors use only one capacitor and are for lower torque applications. Two value cap-start / run motors use two capacitors, a higer value capacitor for starting, and lower value for running. The centrifugal switch switches from the high capacitor to the low capacitor, but the aux windings never leave the circuit. Two-cap motors are for higher torque applications.
In a purely capacitive circuit the current will lead the voltage by 90 degrees. In a purely inductive circuit the current will lag the voltage by 90 degrees. Of course, there is always some resistance in any circuit, so whether inductive or capacitive, the lead / lag relationship between current and voltage will be somewhere between 0 and 90 degrees. I say all that to say this; the net effect of the difference in the capacitor is that it will change the angle of lead / lag between voltage and current in your motor.
In summary, the capacitor provides a delay in the energy given to one of the windings. This delay causes the forces of the motor to be unbalanced and the motor then starts. Economically, capacitor start motors are often more costly due to the inclusion of the capacitor however they have the most starting torque This means that you probably have one in your refrigerator, washer, dryer, or other application where you may need a lot of starting force but you won't find them in your electric fan.
In addition,potential relays are also important. Potential relays are used to electronically connect and disconnect to starting capacitors from the motor circuit . Each relay has a specific voltage rating to place the start capacitor in series with the start winding and a specific voltage to take it out of the circuit. Each rating is based on the electromagnetic field generated by the rotation of the motor. The motor manufacturer studies the effect of placing in and taking out the capacitor to increase starting torque with as little winding flex as possible. Potential relays have four ratings:
(1) continuous coil voltage,
(2) minimum pick-up voltage,
(3) maximum pick-up voltage,
(4) drop out voltage.
A potential relay is difficult to check and should always be replaced when a start capacitor is replaced. The exact size designed for that particular motor must be reinstalled. The potential relay must also be replaced if contacts are found to be open.
Souce from :
http://www.capacitors-china.com
About the Author
Manufacturer of Motor Capacitor in China
Popping Capacitor?