Over Load Relay & Contactor for Starter

 

Over Load Relay & Contactor for Motor Starter:

Types of Over Load Relay:

  1. Class 10: Would Trip after 10 seconds.
  2. Class 20: Would Trip after 20 seconds.
  3. Class 30: Would Trip after 30 seconds.
  • Over Load Relay should be set 115% to 130% of Motor Full Load Current.
  • Class 10 is faster than Class 20 and Class 30 over Load Relay.

Size of over Load Relay:

Size

Amp Capacity

S00

0.1 To 0.4

0.4 To 0.6

1.6 To 6

3 To 12

S0

3 To 12

6 To 25

S2

6 To 25

13 To 50

S3

13 To 50

25 To 100

S6

50 To 200

S10 & S12

55 To 250

200 To 540

300 To 63

Contactor Coil:

Coil Voltage (40 To 50 Hz)Suffix
24VT
48VW
110V To 127VA
220V To 240VB
277VH
380V To 415VL

Type of Contactor for Starter:

Contactor

Application

AC1

Non-Inductive or Slightly Inductive ,Resistive Load

AC2

Slip Ring Motor

AC3

Squirrel Cage Motor

AC4

Rapid Start / Stop

AC5a

Switching of Electrical Discharge Lamp

AC5b

Switching of Electrical Incandescent Lamp

AC6a

Switching of Transformer

AC6b

Switching of Capacitor Bank

AC7a

Slightly Inductive Load in Household or same type load

AC7b

Motor Load in Household Application

AC8a

Hermetic refrigerant Compressor Motor with Manual O/L Reset

AC8b

Hermetic refrigerant Compressor Motor with Auto O/L Reset

AC12

Control of Restive Load and Solid State Load with optocoupler Isolation

AC13

Control of Restive Load and Solid State with T/C Isolation

AC14

Control of Small Electro Magnetic Load ( <72VA)

AC15

Control of Small Electro Magnetic Load ( >72VA)

 Making and Breaking Capacity of Contactor:

ContactorMaking Capacity(Amp)Breaking Capacity (Amp)
AC11.5 X motor rated current1.5 X motor rated current
AC24 X motor rated current4 X motor rated current
AC310 X motor rated current8 X motor rated current
AC412 X motor rated current10 X motor rated current
AC5a3 X motor rated current3 X motor rated current
AC5b1.5 X motor rated current1.5 X motor rated current
AC6a12 X motor rated current10 X motor rated current
AC6b12 X motor rated current10 X motor rated current
AC7a1.5 X motor rated current1.5 X motor rated current
AC7b8 X motor rated current8 X motor rated current
AC8a6 X motor rated current6 X motor rated current
AC8b6 X motor rated current6 X motor rated current
AC12  
AC1310 X motor rated current1.1 X motor rated current
AC146 X motor rated current6 X motor rated current
AC1510 X motor rated current10 X motor rated current

 Contactor Status:

Contactor StatusContinuity Between  Pins (N/C)Non Continuity Between Pins (N/O)

Power Not Applied

32 and 33

21 and 22

11 and 12

A1 and A2

B1 and B2

Power Applied

21 and 22

32 and 33

11 and 12

A1 and A2

B1 and B2

 Main Circuit Voltage of O/L Relay & Contactor:

  1. A.C= 240V,415V
  2. D.C=230V,460V,600V

Contactor’s Coil Voltage:

  1. A.C= 40V,220V,240V,415V
  2. D.C=24V(For PLC),110V,230V,460V

Rated Current of Contactor: (Thermal and Intermediate Duty):

  1. A.C= 6,10,16,25,63,100,160,200,315,400,630,800 Amp
  2. D.C= 16,20,80,160,315,1250,8000 Amp.

Contactor / Relay Setting / Fuse / Cable for DOL STARTER

H.P

KW

FLC

Contactor Size (Amp)

Relay setting

Fuse

Cable (mm2)

Min

Max

Cu

Allu

0.5

0.37

1

–

0.8

1.17

4

1

1.5

0.75

0.55

1.3

9

1

1.5

4

1

1.5

1

0.74

1.9

9

1.6

2.3

6

1.5

2.5

1.5

1.11

2.6

9

2

3

6

1.5

2.5

2

1.49

3.7

9

2.5

3.7

10

1.5

2.5

3

2.2

4.8

9

4

5.9

16

1.5

2.5

5

3.73

7.8

9

6.3

9.4

20

1.5

2.5

7

5.22

11.2

12

8

11.7

25

2.5

4

10

7.46

16

16

12.5

18.7

25

4

6

12.5

9.32

19

32

16

23.4

32

4

6

15

11.19

20.8

32

16

23.4

50

6

10

20

14.92

28

32

20

30

50

6

10

25

18.65

34

38

32

37.4

63

10

16

30

22.38

40

45

32

47

80

16

25

40

29.84

53

63

50

59

100

25

35

50

37.3

65

70

57

65.5

125

25

50

60

44.76

78

85

70

88.9

125

25

50

75

55.95

96

110

85

98.2

160

50

70

100

74.6

131

140

115

168

200

70

95

125

93.25

156

170

115

168

250

120

150

150

111.9

189

205

160

234

315

150

240

180

134.28

227

250

160

234

355

185

300

215

160.39

271

300

200

299

400

–

–

270

201.42

339

400

250

374

500

–

–

335

249.91

338

475

320

468

500

–

–

Relay Range & Back up Fuse for DOL Starter

H.P

KW

Full Load Current (amp)

Relay Rang(Amp)

Back Up Fuse

Min

Max

10

7.5

13.6

13 To 20

25

50

12.5

9.3

17

13 To 20

25

50

15

11.2

20

20 To 30

35

80

20

14.9

28

20 To 30

60

80

25

18.7

35

30 To 45

60

100

30

22.4

40

30 To 45

80

100

35

26.1

47

45 To 63

80

125

Relay Range & Back up Fuse for Star / Delta Starter

H.P

KW

Full Load Current (amp)

Relay Rang(Amp)

Back Up Fuse

Min

Max

20

14.9

28

13 To 20

60

60

25

18.7

35

20 To 30

60

100

30

22.4

40

20 To 30

60

100

35

26.1

47

20 To 30

80

100

40

29.8

55

30 To 35

80

125

50

37.3

66

30 To 35

100

125

60

44.8

80

45 To 63

100

160

75

55.95

95

45 To 63

125

160