MICKS INFORMATION SITE    |   home
MAX Zs   |   About Me   |   Favorite Links   |   MG Type C45   |   MEM Type D   |   Square D Type B,D,4   |   Square D SFA   |   Square D SKA,SKC,SKH   |   Square D SLA,SMA,SMH   |   Federal Type B+C   |   Federal Type D+4   |   Federal Type RCBO   |   Square D Type B+C   |   Telemecanique   |   Title 62   |   Title 64   |   Title 41   |   Title 65   |   Terasaki   |   Allan Bradley   |   Title 68   |   Title 63
MAX Zs
Maximum Zs Values

Maximum measured earth fault loop impedance (ohms) when overcurrent protective device is a circuit breaker to BS 3871,
BS EN 60898, BS EN 61009 (BS7671)

Type
5
6
10
15
16
20
25
30
32
40
45
50
63
80
100
125
1
12.00
10.00
6.00
4.00
3.75
3.00
2.40
2.00
1.88
1.50
1.33
1.20
0.95
-
-
-
2
6.86
5.71
3.43
2.29
2.14
1.71
1.37
1.14
1.07
0.86
0.76
0.69
0.54
-
-
-
B
-
8.00
4.80
-
3.00
2.40
1.92
-
1.50
1.20
-
0.96
0.76
0.60
0.48
0.38
3&C
4.80
4.00
2.40
1.60
1.50
1.20
0.96
0.80
0.75
0.60
0.53
0.48
0.38
0.30
0.24
0.19
D
2.40
2.00
1.20
0.80
0.75
0.60
0.48
0.40
0.38
0.30
0.27
0.24
0.19
0.15
0.12
0.10


Maximum measured earth fault loop impedance (ohms) when overcurrent protective device is a circuit breaker to BS 3871, BS EN 60898, BS EN 61009
(On Site Guide)

Type
5
6
10
15
16
20
25
30
32
40
45
50
63
1
9.60
8.00
4.80
3.20
3.00
2.40
1.92
1.60
1.50
1.20
1.06
0.96
0.76
2
5.49
4.57
2.74
1.83
1.71
1.37
1.10
0.91
0.86
0.69
0.61
0.55
0.43
B
-
6.4
3.84
-
2.40
1.92
1.54
-
1.20
0.96
0.86
0.77
0.61
3&C
3.84
3.20
1.92
1.28
1.20
0.96
0.77
0.64
0.60
0.48
0.42
0.38
0.30
D
1.92
1.60
0.96
0.64
0.60
0.48
0.38
0.32
0.30
0.24
0.22
0.19
0.15


Maximum measured earth fault loop impedance (ohms) when overcurrent protective device is a fuse to BS 88 parts 2 & 6 (BS7671)

6
10
16
20
25
32
40
50
63
80
100
125
160
200
0.4
8.89
5.33
2.82
1.85
1.50
1.09
0.86
0.63
-
-
-
-
-
-
5
14.1
7.74
4.36
3.04
2.40
1.92
1.41
1.09
0.86
0.60
0.44
0.35
0.27
0.20


Maximum measured earth fault loop impedance (ohms) when overcurrent protective device is a fuse to BS 88 parts 2 & 6 (On Site Guide)

6
10
16
20
25
32
40
50
63
0.4
7.11
4.26
2.25
1.48
1.20
0.87
0.68
0.50
-
5
11.28
6.19
3.48
2.43
1.92
1.53
1.12
0.87
0.68


Maximum measured earth fault loop impedance (ohms) when overcurrent protective device is a fuse to BS 1361 (BS7671)

5
15
20
30
45
60
80
100
0.4
10.9
3.43
1.78
1.20
0.60
-
-
-
5
17.1
5.22
2.93
1.92
1.00
0.73
0.52
0.38


Maximum measured earth fault loop impedance (ohms) when overcurrent protective device is a fuse to BS 1361 (On Site Guide)

5
15
20
30
45
60
80
100
0.4
8.72
2.74
1.42
0.96
0.48
-
-
-
5
13.68
4.17
2.34
1.53
0.80
0.58
0.41
0.30


Maximum measured earth fault loop impedance (ohms) when overcurrent protective device is a semi-enclosed fuse to BS 3036
(BS7671)

5
15
20
30
45
60
100
0.4
10.0
2.67
1.85
1.14
0.62
-
-
5
18.5
5.58
4.00
2.76
1.66
1.17
0.56


Maximum measured earth fault loop impedance (ohms) when overcurrent protective device is a semi-enclosed fuse to BS 3036
(On Site Guide)

5
15
20
30
45
60
100
0.4
8.00
2.13
1.48
0.91
0.49
-
-
5
14.80
4.46
3.20
2.20
1.32
0.93
0.44