AC Motor Start Capacitors


AC Motor Start Capacitors Suppliers

We are one of the leading manufacturers of aluminum electrolytic capacitors in India. We are in the field of capacitor manufacturing since last two decades.

"SARADA" name goes with the beginning of capacitors manufactured with latest technologies covering entire range of Electrolytic AC motor start capacitors and DC capacitors as well as MPP AC capacitors.

Since, business is undergoing a sea change these days and the time has come to look into the various factors of business to make it more professional in order to make our products acceptable to the industrial society. It is necessary to make our products more relevant, cost effective and competitive.

A number of programmes have been developed by experienced professional to improve a high quality of capacitor production. Rigorous testing are carried out from inward to final inspection as per Standard/Customer specification. The production of high quality capacitors is enhanced by our own technological development and modern sophisticated equipment.

We use the best quality of raw materials globally available, specially from France, Germany, Italy and Japan.

Our " SARADA" AC motor start capacitors are tested by Electronics Regional Test Laboratory (North), New Delhi.

"SARADA" AC motor start capacitor are manufactured by using etched and formed super purity aluminum foils, separating anode and cathode by special low density tissue paper to hold enough electrolyte and absorbent and supported by sandwiched duplex paper. The capacitor element is sealed into an aluminum can to prevent it from atmospheric moisture and dust. These capacitors are fully insulated by means of PVC sleeve and again sealed into an outer can for added safety towards electrical hazards. The flexible termination of suitable length is taken out.

CONNECTION OF MOTOR START CAPACITORS:

Among various types of single phase motors, the motor start capacitor is the most widely used type. In this type of motor, the starting torque is achieved by connecting a capacitor in series with the starting winding. A higher torque is obtained with a lower starting current, when compared to other types of single phase motors.

These motors are therefore eminently suited for apparatus having heavy starting duty. Motor start capacitors are fitted with a centrifugal switch which automatically disconnects the auxiliary winding when the motor attains a pre-determined speed and therefore works only with the help of the main winding (Refer Circuit). The capacitor is marked with two voltages (230/275) the higher voltage being the surge voltage and lower voltage being the rated peak operating voltage. The capacitor dielectric is built on to withstand this voltage only and a higher voltage likely to cause rupture. The surge voltage rated must be adequate for the maximum RMS value experience with motor concerned.

Image Missing

CAPACITANCE:

Capacitors are generally marked with minimum and maximum capacitance values in MFD (Micro farad) and the actual value will be between the two values mentioned. For example: A capacitor marked 100/120 MFD will have a capacitance between 100 MFD and 120 MFD.

Capacitance of the capacitor can be measure by a simple impedence methods as per circuit -2, using a voltmeter, ammeter and low loss wattmeter. The current should be measured within 3 Sec, after charging the capacitor.

Capacitance "C" can be calculated as follows:

Capacitance "C" at 50 Hz = 3180xI/V (MFD)

V

Where I = RMS value of current in amperes.

V = RMS value of test voltage in volts.

Image Missing

POWER FACTOR/TANGENT OF LOST ANGLES:

The Tangent of loss angle is calculated as follows:

Tan d (%) = Wx100%

V X I

Where, W = Watt

I & V = Same as measured in capacitance

ENSURE WHEN REPLACING/CHANGING THE CAPACITOR:

While replacing a defective capacitor it must be ensured that correct rating is chosen. A higher capacitance can cause excessive current and lower capacitance can cause insufficient torque current.

IMPORTANT POINTS TO REPAIRERS/USERS:

If a capacitor fails, it is often due to the fault developed in the associated equipment. Hence, the following points to be checked in the motor.

  1. Check if any motor fault
  2. Check if any dry ball bearings
  3. Check if any defective centrifugal switch, which leave the capacitor connected for too long period
  4. Check if any mechanical mis-alignment
  5. Check if low capacitance resulting high voltage across the capacitor
  6. Check if any tight belt

SALIENT FEATURES:

  1. Heavy duty applications
  2. More resistance to vibration
  3. Available in well insulated DOUBLE CAN construction for added safety towards electrical hazards and also in SINGLE CAN construction
  4. Compact and elegant design for easier handling and space saving
  5. BAKELITE CANS and STUD TYPE CANS also available on request

APPLICATION:

  1. Especially used in single-phase motors
  2. Compressors
  3. Elevators
  4. Compressor of air conditioners, refrigerators and air-coolers
  5. Special type heavy duty motor start capacitors for compressors, garage door opener and big industrial motors for specific needs

TECHNICAL FEATURES:

1

Operating temperature range

-300 oc to +700oc

2

Operating frequency range

40 Hz to 60 Hz

3

Capacitance range

(@100 Hz & 25 0 c )

20 Mfd to 1350 Mfd

4

Voltage range

63v ac to 415v ac

5

Surge voltage

275v ac for 230v ac rate capacitor

6

Power factor/tangent of loss angle (230v ac,50 Hz & 25 0 c)

10% maximum

7

Duty cycle

20 starts per hour maximum, each start not more than 3 seconds duration at rated voltage after every 3 minutes. By reducing the time duration of start operation to which the capacitor is subjected. It is possible to use the capacitor for a large number of however being 60 starts operation per hour each of duration not exceeding 3 seconds.

8

Insulation voltage

It can withstand 2000 VAC for 1 minute between termination and outer case.

9

Insulation resistance

Minimum 100 M between leads and the case.

10

Polarity

May be connected either way

11

Shelf life

Can be stored for one hear without damage. Deterioration takes place if the capacitor is stored for long period and it is necessary that re-charging is done before the capacitor is subjected to its full duty. This can be done applying the rated voltage to capacitor for 2 or 3 seconds at a time. This can be repeated by 3 times before use. But a total of 10 seconds must not be exceeded. If the capacitor is already connected to the motor, the same effect can be obtained by switching on the motor several times before the load to be connected. So that it is in circuit for minimum period. Following a cooling period of 5 to 10 minutes, the capacitor/motor can be operated normally

12

Other test

IS: 2993-1998

CAPACITANCE RANGE AND CAN SIZE FOR DIFFERENT RATING OF MOTORS:

CAPACITANCE RANGE (MFD)
MOTOR RATING (hp)
CAN SIZE

 

SINGLE CAN

Dia X Length (mm)

DOUBLE CAN

Dia X Length (mm)

20 - 30

1/8

35 X 55

40 X 82

30 - 40

1/6

35 X 55

40 X 82

40 - 60

1/4

35 X 55

40 X 82

60 - 80

1/3

35 X 80

40 X 105

80 - 100

1/2

35 X 80

40 X 105

100 - 120

3/4

35 X 80 / 40 X 80

40 X 105/45 X 105

120 - 150

1

40 X 80

45 X 105

150 - 200

1- 1/4

40 X 110

45 X 135 / 50 X 135

200 - 250

Above 1 -1 1/4 and upto 2

40 X 110

45 X 135 / 50 X 135

  • Other sizes/values are available on request.
  • The technical specification and availability of the products specified in this catalogue are subject to change due to availability of better raw material and improved design.