Bussmann
®
Square Body – US Style
1250V/1300V (IEC/U.L.)
50-1400A
Electrical Characteristics
Size
50
63
80
100
125
160
200
250
315
350
160
200
250
315
350
400
450
†500
†550
‡630
250
280
315
350
400
450
500
550
630
†700
†800
‡900
‡1000
315
350
400
450
500
550
630
700
800
900
¥1000
¥1100
¥1250
¥1400
1*
1
2
3
¥
n
n
n
n
Rated
Current
RMS-Amps
Pre-arc
I2t (A2S)
Clearing
at 1000V
135
215
420
750
1450
2600
5150
9200
18500
27000
1900
3800
7750
15000
20000
29500
42000
69500
95000
130000
6500
9350
13000
16500
23000
34000
48000
62000
115000
160000
245000
360000
480000
9500
13500
19500
31000
39000
55000
83500
115000
205000
305000
450000
575000
810000
1250000
815
1300
2500
4450
9000
16000
31000
54500
115000
165000
11500
22500
46000
90000
125000
175000
250000
340000
465000
660000
38500
55500
77500
97500
140000
205000
285000
370000
575000
795000
1200000
1750000
2350000
58000
81500
120000
185000
235000
325000
495000
705000
995000
1500000
2150000
2800000
3950000
6000000
R
®
Ordering Information
Clearing
at 1250V
Watts
Loss
-FU/115
Visual
Indicator
-FKE/115
Type K
Indicator
for Micro
1100
1750
3350
5950
11500
21000
41000
73000
150000
220000
15500
30000
61500
120000
165000
235000
335000
15
20
25
30
35
40
45
55
60
65
45
50
60
65
70
75
80
85
95
100
65
70
75
80
85
90
95
100
110
115
120
125
135
185
90
95
100
105
110
115
120
125
130
135
140
145
150
170M3688
170M3689
170M3690
170M3691
170M3692
170M3693
170M3694
170M3695
170M3696
170M3697
170M4688
170M4689
170M4690
170M4691
170M4692
170M4693
170M4694
170M4695
170M4696
170M4697
170M5688
170M5689
170M5690
170M5691
170M5692
170M5693
170M5694
170M5695
170M5696
170M5697
170M5698
170M5699
170M5700
170M6688
170M6689
170M6690
170M6691
170M6692
170M6693
170M6694
170M6695
170M6696
170M6697
†170M6698
†170M6699
‡170M6700
‡170M6701
170M3738
170M3739
170M3740
170M3741
170M3742
170M3743
170M3744
170M3745
170M3746
170M3747
170M4738
170M4739
170M4740
170M4741
170M4742
170M4743
170M4744
170M4745
170M4746
170M4747
170M5738
170M5739
170M5740
170M5741
170M5742
170M5743
170M5744
170M5745
170M5746
170M5747
170M5748
170M5749
170M5750
170M6738
170M6739
170M6740
170M6741
170M6742
170M6743
170M6744
170M6745
170M6746
170M6747
†170M6748
†170M6749
‡170M6750
‡170M6751
51500
74500
105000
135000
180000
270000
380000
495000
730000
77500
110000
160000
245000
310000
435000
665000
940000
1300000
1900000
U.L. Recognition at 1000V.
Interrupting rating 100kA RMS Symmetrical.
Watts loss provided at rated current.
Rated voltage (IEC) †1100 ‡1000V (Consult Bussmann for U.L. Recognition/ CSA Component Acceptance status.)
Microswitch indicator ordered separately.
7-11-01
SB01191
Curves
Carton
Qty.
Carton
Weight
(kg)
BIF #
1
0.425
17056630
1
0.675
17056632
1
0.740
17056634
1
1.250
17056636
1 kg = 2.2 lbs.
1 lb = 0.45 kg
Form No.
Page 1 of 2
BIF Doc #720032
Bussmann
®
Square Body – US Style
1250V/1300V (IEC/U.L.)
R
50-1400A
®
Electrical Characteristics
Total Clearing I2t
The total clearing I2t at rated voltage and
at power factor of 15% are given in the
electrical characteristics. For other voltages, the clearing I2t is found by multiplying by correction factor, K , given as
a function of applied working voltage,
E g , (RMS).
Arc Voltage
This curve gives the peak arc voltage,
U L , which may appear across the fuse
during its operation as a function of the
applied working voltage, E g , (RMS) at a
power factor of 15%.
1.5
K
1.25
1.0
3
2.5
Power Losses
Watts loss at rated current is given in
the electrical characteristics. The curve
allows the calculation of the power
losses at load currents lower than the
rated current . The correction factor, K p ,
is given as a function of the RMS load
current, Ib , in % of the rated current .
1.0
Kp
0.8
UL
0.6
0.5
1.8
1.4
0.4
0.5
0.4
103
8
0.3
0.3
6
5
0.2
0.2
4
Eg
400
600
800
Eg
3
400
1000 1200 1400
600
800
Ib
0.1
30 40 50
1000 1200 1400
60
70
80 90 100%
-----Dashed lines apply to the following amperages:
Size
Amp
1*
400
1
500-630
2
630-1000
3
800-1400
Dimensions
US Style: Type -FU/115, -FKE/115
Size
1*
1
2
3
B
C1
C2
D
E
H
I
156
160
160
159
130
127
127
128
101
102
102
101
59
69
77
92
45
53
61
76
20
25
25
36
10
14
14
16
B
Dimension in mm.
1mm = 0.0394∑
1∑ = 25.4mm
6
74
D
C1
E
C2
E
I
H
This bulletin is intended to clearly present comprehensive product data and provide technical information that will help the end user with design applications. Bussmann reserves the right,
without notice, to change design or construction of any products and to discontinue or limit distribution of any products. Bussmann also reserves the right to change or update, without
notice, any technical information contained in this bulletin. Once a product has been selected, it should be tested by the user in all possible applications.
7-11-01
SB01191
Form No.
Page 2 of 2
BIF Doc #720032