Brochure
Table Of Contents
- Introduction
- Motor Failure and Protection
- Trip Class Designation
- Withstand Ratings
- Thermal Overload Relay
- Melting Alloy
- Non-Compensated Bimetallic
- Automatic Reset
- Ambient Temperature Compensated Bimetallic
- Thermal Overload Relay Trip Characteristics
- Solid State Overload Relay
- Additional Standard Features
- Optional Features
- Additional Standard Features
- Optional Features
- General
- Nameplate Versus NEC Full-load Current
- Service Factor
- Motor Branch Circuit Design
- Overload Relays
- Hand Reset Melting Alloy
- Accessories
- Isolated Auxiliary Contacts for Motor Logic Overload Relays
- DIN Adapter
- Lug-Lug/Lug-Extender Kits
- Remote Reset Module
- 4 – 20 ma DC Communication Module
- Contact Units for Melting Alloy Type Overload Relays
- Melting Alloy Overload Relay Jumper Strap Kits
- Bimetallic Overload Relays
- Motor Logic™ – Solid State Overload Relay
35
5/98
© 1998 Square D All Rights Reserved
Thermal Unit Selection
Tables 84 thru 91
Table 89
Motor Full-Load
Current (Amp)
Thermal Unit
Number
10.0-11.1
11.2-12.0
12.1-13.3
B 17.5
B 19.5
B 22
13.4-15.1
15.2-17.1
17.2-18.6
B 25
B 28.0
B 32
18.7-21.4
21.5-25.7
25.8-28.2
B 36
B 40
B 45
28.3-29.7
29.8-31.2
31.3-32.1
B 50
B 56
B 62
32.2-35.7
35.8-40.7
40.8-48.0
B 70
B 79
B 88
Table 86
Motor Full-Load
Current (Amp)
Thermal Unit
Number
0.43-0.44
0.45-0.47
0.48-0.53
A .49
A .54
A .59
0.54-0.61
0.62-0.65
0.66-0.71
A .65
A .71
A .78
0.72-0.79
0.80-0.86
0.87-0.96
A .86
A .95
A 1.02
0.97-1.04
1.05-1.17
1.18-1.31
A 1.16
A 1.25
A 1.39
1.32-1.38
1.39-1.47
1.48-1.57
A 1.54
A 1.63
A 1.75
1.58-1.65
1.66-1.77
1.78-1.93
A 1.86
A 1.99
A 2.15
1.94-2.18
2.19-2.46
2.47-2.68
A 2.31
A 2.57
A 2.81
2.69-2.87
2.88-3.07
3.08-3.59
A 3.61
A 3.95
A 4.32
3.60-3.79
3.80-4.27
4.28-4.59
A 4.79
A 5.30
A 5.78
4.60-4.90
4.91-5.06
5.07-5.44
A 6.20
A 6.99
A 7.65
5.45-6.24
6.25-7.21
7.22-7.69
A 8.38
A 9.25
A 9.85
7.70-8.24
8.25-8.81
8.82-9.32
A 11.0
A 11.9
A 132
9.33-9.99
10.0-10.5
10.6-11.5
A 14.1
A 14.8
A 16.2
11.6-12.2
12.3-13.3
13.4-15.8
A 17.9
A 21.3
A 25.2
15.9-18.4
18.5-20.5
20.6-21.5
A 27.1
A 29.5
A 31.9
21.6-23.9
24.0-26.8
26.9-28.2
A 33.8
A 35.9
A 40.0
28.3-29.8
29.9-32.0
A 42.3
A 44.7
Table 87
Motor Full-Load
Current (Amp)
Thermal Unit
Number
0.40-0.41
0.42-0.45
0.46-0.51
A .49
A .54
A .59
0.52-0.58
0.59-0.63
0.64-0.68
A .65
A .71
A .78
0.69-0.76
0.77-0.83
0.84-0.93
A .86
A .95
A 1.02
0.94-1.01
1.02-1.14
1.15-1.28
A 1.16
A 1.25
A 1.39
1.29-1.34
1.35-1.44
1.45-1.55
A 1.54
A 1.63
A 1.75
1.56-1.61
1.62-1.71
1.72-1.85
A 1.86
A 1.99
A 2.15
1.86-2.04
2.05-2.38
2.39-2.60
A 2.31
A 2.57
A 2.81
2.61-2.77
2.78-2.98
2.99-3.40
A 3.61
A 3.95
A 4.32
3.41-3.64
3.65-4.08
4.09-4.38
A 4.79
A 5.30
A 5.78
4.39-4.68
4.69-4.79
4.80-5.11
A 6.20
A 6.99
A 7.65
5.12-5.84
5.85-6.70
6.71-7.18
A 8.38
A 9.25
A 9.85
7.19-7.70
7.71-8.14
8.15-8.56
A 11.0
A 11.9
A 13.2
8.57-9.15
9.16-9.80
9.81-10.6
A 14.1
A 14.8
A 16.2
10.7-11.0 A 17.9
Table 88
Motor Full-Load
Current (Amp)
Thermal Unit
Number
0.39-0.40
0.41-0.44
0.45-0.49
A .49
A .54
A .59
0.50-0.57
0.58-0.61
0.62-0.66
A .65
A .71
A .78
0.67-0.73
0.74-0.80
0.81-0.90
A .86
A .95
A 1.02
0.91-0.97
0.98-1.09
1.10-1.23
A 1.16
A 1.25
A 1.39
1.24-1.57
1.58-1.66
1.67-1.79
A 1.86
A 1.99
A 2.15
1.80-1.99
2.00-2.31
2.32-2.50
A 2.31
A 2.57
A 2.81
2.51-2.66
2.67-2.85
2.86-3.26
A 3.61
A 3.95
A 4.32
3.27-3.49
3.50-3.92
3.93-4.20
A 4.79
A 5.30
A 5.78
4.21-4.49
4.50-4.64
4.65-4.94
A 6.20
A 6.99
A 7.65
4.95-5.62
5.63-6.39
6.40-6.82
A 8.38
A 9.25
A 9.85
6.83-7.27
7.28-7.71
7.72-8.13
A 11.0
A 11.9
A 13.2
8.14-8.64
8.65-9.15
9.16-9.97
A 14.1
A 14.8
A 16.2
9.98-11.0 A 17.9
Table 84
Motor Full-Load
Current (Amp)
Thermal Unit
Number
3.38-3.78
3.79-4.37
4.38-4.87
FB 4.75
FB 5.3
FB 6.1
4.88-5.51
5.52-5.73
5.74-6.09
FB 6.75
FB 7.45
FB 7.8
6.10-6.44
6.45-6.75
6.76-7.15
FB 8.21
FB 8.6
FB 9.0
7.16-7.57
7.58-8.07
8.08-8.47
FB 9.5
FB 10
FB 10.6
8.48-8.81
8.82-9.46
9.47-10.1
FB 11.2
FB 12.1
FB 13.1
10.2-10.8
10.9-11.4
11.5-12.1
FB 13.9
FB 14.8
FB 15.6
12.2-13.1
13.2-13.8
13.9-14.8
FB 16.4
FB 17.6
FB 18.4
14.9-16.1
16.2-17.4
17.5-18.3
FB 19.4
FB 21.1
FB 22.6
18.4-19.5
19.6-21.0
21.1-22.5
FB 23.6
FB 24.8
FB 26.7
22.6-23.7
23.8-24.5
24.6-26.4
FB 28.3
FB 29.6
FB 30.5
26.5-27.7
27.8-28.7
28.8-29.9
FB 32.6
FB 34.1
FB 35
30.0-31.8
31.9-33.5
33.6-35.1
FB 36.6
FB 38.3
FB 40.2
35.2-37.1
37.2-38.8
38.9-41.1
FB 42
FB 44
FB 46
41.2-45.0 FB 48
Table 91
Motor Full-load
Current (Amp)
Thermal Unit
Number
4.80-5.07
5.08-5.73
5.74-6.48
A 7.65
A 8.38
A 9.25
6.49-6.90
6.91-7.25
7.26-7.81
A 9.85
A 11.0
A 11.9
7.82-8.29
8.30-8.81
8.82-9.40
A 13.2
A 14.1
A 14.8
9.41-10.0
10.1-11.1
11.2-11.7
A 16.2
A 17.9
A 21.3
11.8-13.7
13.8-16.0
13.1-16.9
A 25.2
A 27.1
A 29.5
17.0-17.7
17.8-18.7
18.8-20.2
A 31.9
A 33.8
A 35.9
20.3-21.4
21.5-22.5
22.6-23.8
A 40.0
A 42.3
A 44.7
23.9-26.0 A48.0
Table 90
Motor Full-Load
Current (Amp)
Thermal Unit
Number
4.88-5.13
5.14-5.85
5.86-6.67
A7.65
A8.38
A9.25
6.68-7.09
7.10-7.62
7.63-8.04
A9.85
A11.0
A11.9
8.05-8.46
8.47-9.11
9.12-9.69
A13.2
A14.1
A14.8
9.70-10.5
10.6-11.6
11.7-12.3
A16.2
A17.9
A21.3
12.4-14.6
14.7-16.8
16.9-17.9
A25.2
A27.1
A29.5
18.0-18.7
18.8-19.8
19.9-21.4
A31.9
A33.8
A35.9
21.5-22.8
22.9-23.8
23.9-26.0
A40.0
A42.3
A44.7
Table 85
Motor Full-Load
Current (Amp)
Thermal Unit
Number
42.9-45.4
45.6-48.3
48.4-52.4
FB 44
FB 46
FB 48
52.5-55.9
56.0-59.8
59.9-63.8
FB 50.5
FB 52.5
FB 55.5
63.9-67.9
68.0-72.6
72.7-83.2
FB 58
FB 60
FB 63.5
83.3-94.7
94.8-105
106-116
FB 69
FB 77
FB 84
117-121
122-133
FB 92
FB 105