BRITISH STYLE–
SEMICONDUCTOR PROTECTION FUSES
The Edison British Style semiconductor protection fuses
include a 660VAC line utilizing new filler technology. These
new fuses have greatly reduced peak let-through current
and energy under fault conditions and hence extend fuse
protection capability. They can be recognized by the letter
“F” in their catalog number. Application and technical data
for these 660VAC “F” fuses and the original line of 240VAC
British “T” type fuses are presented on the following pages.
Replacement Table — “T” to “F” (660V)
Earlier
“T” Range
6CT
10CT
12CT
16CT
20CT
25ET
32ET
35ET
40ET
45ET
56ET
63ET
–
–
80ET
65EET
75EET
90EET
110EET
–
140EET
–
160EET
–
160MT
180MT
200MT
–
250MT
280MT
315MT
355MT
180MMT
200MMT
225MMT
280MMT
315MMT
355MMT
–
–
400MMT
450MMT
500MMT
560MMT
630MMT
710MMT
New “F” Range
Lowest
Rating
6FC
10FC
12FC
16FC
20FC
–
35FE
35FE
40FE
45FE
63FE
63FE
–
–
80FE
–
–
–
–
–
140FEE
–
160FEE
–
200FM
225FM
250FM
280FM
315FM
350FM
350FM
350MT
180FM
200FM
225FM
280FM
315FM
350FM
–
–
500FMM
550FMM
630FMM
700FMM
700FMM
700FMM
Highest
Rating
6FC
10FC
12FC
16FC
20FC
–
35FE
40FE
45FE
50FE
63FE
71FE
80FE
90FE
100FE
–
–
100FEE
120FEE
140FEE
160FEE
180FEE
200FEE
180FM
200FM
225FM
250FM
280FM
315FM
350FM
350FM
350FM
180FM
200FM
225FM
280FM
315FM
350FM
400FMM
450FMM
500FMM
550FMM
630FMM
700FMM
700FMM
700FMM
“F” Range
This is a superior design of fuses in the same physical
package as the “T” range.
Equivalent Ratings
This table shows the suggested equivalent ratings to
replace a “T” with an “F”.
Because of the new design technology it has been possible
to obtain the equivalent energy let-through I
2
t with a higher
amp rated fuse hence reducing the possibility of premature
operation.
This table gives a range of suggested acceptable new “F”
type to replace the earlier “T” type.
To upgrade your protection to the new “F” series select a
fuse rating within the range shown that suits your circuit
inrush requirements. You will still have the same or better
protection of your semiconductor devices.
It should be remembered that to protect devices we must
consider the energy let-through of the selected fuse. The
label amp rating will relate to the full load current and the
circuit inrush amps.
The suggested replacements are based on:
a. Similar surge withstand to normal circuit overloads.
b. Lower total I
2
t let-through.
This gives enhanced reliability due to the use of a higher
current rated fuse which avoids nuisance operation and still
gives improved short-circuit protection.
84
BRITISH STYLE–
SEMICONDUCTOR PROTECTION FUSES
240 VOLT (AC) RANGE
Type
Outline
Part
Number
Pre-arc
I
2
t (A
2
SEC)
Clearing
At 120V
Clearing
At 240V
Watts
Loss
D.C.
Volts
Carton
Qty.
Carton
Weight
(Kg)
LCT
1.50"
38.0mm
6LCT
10LCT
12LCT
16LCT
20LCT
2
3.8
7
20
25
6
12
22
50
80
9
22
32
100
160
1.0
2.5
2.5
2.5
4.0
200
20
20
20
20
20
0.110
0.110
0.110
0.110
0.110
LET
1.65"
41.8mm
7LET
10LET
12LET
16LET
25LET
32LET
35LET
50LET
63LET
80LET
100LET
125LET
160LET
180LET
1.7
3.8
7
15
18
32
50
100
180
300
600
600
1100
1600
10
23
42
70
120
200
320
500
1100
1900
3800
3800
7000
12000
17
35
58
140
250
450
600
1400
2200
3800
7500
7500
18000
29000
1.5
1.8
2
2.5
4.0
5.0
5.0
7.0
9.0
10.0
10.0
10.0
20.0
21.0
140
10
10
10
10
10
10
10
10
10
10
10
10
10
10
0.310
0.310
0.310
0.310
0.310
0.310
0.310
0.310
0.310
0.310
0.310
0.310
0.310
0.310
LMT
2.32"
59.0mm
160LMT
200LMT
250LMT
315LMT
355LMT
400LMT
450LMT
1100
1500
3200
6000
8000
14000
18000
7000
10000
20000
35000
50000
70000
100000
16000
20000
40000
75000
100000
160000
220000
17.0
28.0
28.0
35.0
35.0
40.0
42.0
160
1
1
1
1
1
1
1
0.180
0.180
0.180
0.180
0.180
0.180
0.180
LMMT
400LMMT
400LMMT
400LMMT
400LMMT
400LMMT
400LMMT
2.32"
59.0mm
6000
14000
24000
32000
52000
75000
35000
80000
150000
200000
300000
400000
80000
170000
300000
460000
600000
800000
60.0
64.0
75.0
77.0
82.0
97.0
160
1
1
1
1
1
1
0.370
0.370
0.370
0.370
0.370
0.370
• Interrupting rating 200kA RMS Symmetrical.
• Watts loss provided at rated current.
• All fuses above have been tested to 318VAC.
• These fuses meet the requirements of BS 88 Part 4 and IEC 269-4
• UL Recognition on LET and LMT. Others pending – Consult Edison.
86