NCLR CLASS RK1 FAST-ACTING FUSES
SCLR CLASS RK1 FAST-ACTING FUSES
Catalog Number NCLR (1 - 600A) 250 Volts AC or Less
Catalog Number SCLR (1 - 600A) 600 Volts AC or Less
1
3
4
5
6
8
10
12
15
20
25
30
1
2
3
4
5
6
8
10
12
15
20
25
AMPERE RATINGS
NCLR 250V
35
80
40
90
45
100
50
110
60
125
70
150
SCLR 600V
30
70
35
80
40
90
45
100
50
110
60
125
NCLR/SCLR SPECIFICATIONS
Fast-Acting
175
200
225
250
300
350
400
450
500
600
—
—
150
175
200
225
250
300
350
400
450
500
600
—
BENEFITS:
• No intentional time-delay; opens quickly on overload current.
• Extremely current limiting silver link construction; provides
superior component circuit protection.
APPLICATIONS:
• Recommended for protection on non-inductive loads such
as lighting and resistance heating circuits.
• Use to protect lower interrupting rating circuit breakers in
series rated applications.
Voltage Rating:
NCLR - 250VAC, SCLR - 600VAC
Ampere Rating:
1 - 600 Amps
Interrupting Rating:
200,000 RMS Symmetrical Amps
Current Limiting:
RK1 Fuse
Agency Approvals:
UL Listed, Class RK1, Guide JDDZ, File E162363
CSA Certified HRCI-R per C22.2, No. 248.12
Self-Certified DC Ratings:
Voltage Rating: NCLR (1-600) 250VDC
SCLR (1-600) 300VDC
Interrupting Rating: NCLR/SCLR 10,000 Amperes DC
RECOMMENDED FUSEBLOCKS:
Refer to page 136 in this catalog.
RECOMMENDED UPGRADE:
LENRK/LESRK.
VOLTS
250
600
EDISON
NCLR
SCLR
CROSS REFERENCE
BUSSMANN
GOULD
KTN-R
A2KR
KTS-R
A6KR*
LITTELFUSE
KLNR
KLSR*
* Larger body size on blade type.
11
NCLR CLASS RK1 FAST-ACTING FUSES
SCLR CLASS RK 1 FAST-ACTING FUSES
Application:
Edison NCLR/SCLR Class RK1 fast acting fuses are recommended for general power distribution system use for main,
feeder and branch circuits having a high percentage of noninductive loads such as heating and lighting. NCLR/SCLR
fuses are suitable for circuit breaker protection.* When
NCLR/SCLR fast acting fuses are used for inductive loads,
the fuses usually require oversizing to override normal transient current surges of motors and transformers. Oversizing
fuses usually increases fuse and equipment cost and
reduces overcurrent protection. (For inductive loads,
LENRK/LESRK fuses are recommended). NCLR/SCLR
Class RK1 fast acting fuses are physically interchangeable
with other Class R fuses. They will replace Class K or Class
H fuses in standard fuse clips.
*When used as recommended by a specific circuit breaker manufacturer for a
specific application.
AVERAGE TIME/CURRENT CURVE
400A
600A
600
800
1,000
200A
100A
60A
30A
Cat. No. NCLR (Amp) 250V and SCLR (Amp) 600V
AMPERE
RATING
300
200
100
80
60
40
30
20
10
8
6
TIME IN SECONDS
4
3
2
1
.8
.6
.4
.3
.2
.1
.08
.06
.04
.03
.02
RMS SYMMETRICAL CURRENT IN AMPERES
12
8,000
10,000
6,000
4,000
3,000
2,000
400
300
200
80
100
60
40
.01
NCLR CLASS RK1 FAST-ACTING FUSES
SCLR CLASS RK1 FAST-ACTING FUSES
PEAK LET-THROUGH CURRENT CURVES*
NCLR (250V)
SCLR (600V)
B
400,000
30
3,000
A
RMS SYMMETRICAL CURRENTS IN AMPERES
A–B=ASYMMETRICAL AVAILABLE PEAK (2.3 X SYMM RMS AMPS)
AMPERE
RATING
30
6,000
5,000
4,000
3,000
A
2,000
1,000
200,000
80,000
100,000
40,000
50,000
60,000
30,000
20,000
8,000
10,000
4,000
5,000
6,000
3,000
2,000
2,000
60
8,000
200,000
6,000
5,000
4,000
10,000
80,000
100,000
60
8,000
100
40,000
50,000
60,000
10,000
200
20,000
30,000
100
30,000
20,000
200
20,000
8,000
10,000
30,000
400
4,000
5,000
6,000
400
600
60,000
50,000
40,000
3,000
600
60,000
50,000
40,000
100,000
80,000
2,000
100,000
80,000
200,000
1,000
AMPERE
RATING
200,000
INSTANTANEOUS PEAK LET-THRU CURRENT IN AMPS
300,000
1,000
INSTANTANEOUS PEAK LET-THRU CURRENT IN AMPS
300,000
1,000
B
400,000
RMS SYMMETRICAL CURRENTS IN AMPERES
A–B=ASYMMETRICAL AVAILABLE PEAK (2.3 X SYMM RMS AMPS)
*Curves test data obtained at 15% short-circuit power factor when possible.
CURRENT LIMITATION TABLES**
NCLR (250V)
SCLR (600V)
NCLR – RMS & Peak Let-Thru Currents (kA)
SCLR – RMS & Peak Let-Thru Currents (kA)
Prosp.
Short
C.C.
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
50,000
60,000
70,000
80,000
90,000
100,000
150,000
200,000
Fuse Size
30
IRMS Ip
1
2
1
2
1
3
1
3
1
3
1
3
1
3
1
3
2
4
2
4
2
4
2
4
2
4
2
4
2
5
2
5
60
IRMS
1
1
2
2
2
2
2
2
2
2
3
3
3
3
3
3
Ip
3
3
4
4
5
5
5
5
5
6
6
6
6
7
7
8
100
IRMS
2
2
2
3
3
3
3
3
4
4
4
4
5
5
5
6
Ip
4
5
6
6
7
7
8
8
9
9
9
10
10
11
13
14
200
IRMS
3
3
4
4
4
5
5
5
6
6
6
7
7
7
8
9
Ip
6
8
9
10
10
11
12
12
13
14
15
15
16
17
19
21
400
IRMS
5
6
7
8
9
10
10
10
11
12
13
13
13
14
16
18
Ip
10
14
17
19
20
22
23
24
26
28
29
30
31
32
37
41
600
IRMS
5
8
10
11
12
13
13
14
15
17
17
18
19
20
23
26
Ip
12
19
22
25
27
29
31
32
36
38
40
42
44
46
53
59
Prosp.
Short
C.C.
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
50,000
60,000
70,000
80,000
90,000
100,000
150,000
200,000
Fuse Size
30
IRMS Ip
1
2
1
2
1
3
1
3
1
3
1
3
2
4
2
4
2
4
2
4
2
4
2
4
2
5
2
5
2
5
3
6
60
IRMS
1
2
2
2
2
2
2
2
3
3
3
3
3
3
4
4
Ip
3
4
4
5
5
5
5
6
6
6
7
7
7
7
8
9
100
IRMS
2
2
3
3
3
3
4
4
4
4
5
5
5
5
6
7
Ip
4
5
6
7
7
8
8
9
9
10
10
11
12
12
14
15
200
IRMS
3
4
4
5
5
5
6
6
6
7
7
7
8
8
9
10
Ip
6
8
10
11
12
13
13
14
14
15
16
17
18
19
21
23
400
IRMS
5
7
8
9
10
10
11
11
12
13
14
14
15
16
18
20
Ip
12
15
18
20
22
24
25
26
28
30
32
33
35
36
41
46
600
IRMS
5
9
11
12
13
14
15
16
17
19
20
21
22
23
26
29
Ip
12
20
24
28
31
33
35
37
40
43
45
48
50
52
60
66
*"Apparent Let-Thru Amperes" values are read from "Peak Let-Through Current Curves" and the peak current value divided by 2.3
Asymmetry Factor.
13