4 of 6

Class T Fuses

JLLS Series

Littelfuse.com/JLLS

©2022 Littelfuse, Inc.

Specifications are subject to change without notice.

Revised: 07/14/2022

Current-Limiting Effects

SHORT

CIRCUIT

CURRENT*

APPARENT RMS SYMMETRICAL CURRENT FOR VARIOUS FUSE RATINGS

30 A

60 A

100 A

200 A

400 A

600 A

800 A

1200 A

5,000

750

1,225

1,810

2,500

4,600

5,000

5,000

5,000

10,000

945

1,525

2,300

3,150

6,000

8,500

9,400

10,000

15,000

1,050

1,700

2,610

3,600

6,600

9,750

10,500

13,000

20,000

1,150

1,900

2,900

3,950

7,250

10,500

11,000

14,750

25,000

1,300

2,050

3,100

4,250

8,000

11,500

12,500

15,500

30,000

1,375

2,150

3,300

4,500

8,250

12,000

13,750

16,500

35,000

1,400

2,250

3,500

4,750

8,500

13,000

14,000

17,000

40,000

1,425

2,400

3,650

4,950

8,700

14,000

14,750

18,000

50,000

1,600

2,450

3,900

5,350

9,500

14,500

16,000

20,000

60,000

1,650

2,625

4,150

5,650

10,000

15,500

17,300

21,000

80,000

1,825

2,800

4,570

6,250

11,000

17,000

18,750

23,000

100,000

2,000

3,100

4,950

6,700

12,000

18,000

20,000

25,000

150,000

2,250

3,400

5,650

7,700

13,000

21,000

23,000

28,500

200,000

2,450

3,800

6,200

8,450

15,000

23,000

25,000

31,000

*Prospective RMS Symmetrical Amperes Short-Circuit Current

Note: Data Derived from Peak Let-Thru Curve

- DATA GENERATED IN EXCEL -

100

1,000

10,000

100,000

1,000,000

100

1,000

10,000

100,000

AVAILABLE FAULT CURRENT

SYMMETRICAL R.M.S. AMPERES

800A -

600A -

500A -

400A -

200A -

100A -

60A -

30A -

BASIS FOR DATA:

TEST VOLTAGE: 600V

TIME CONSTANT/POWER FACTOR:

FUSE CATALOG NUMBER:

DRAWN BY:

DATE:

REVISION:

DRAWING NO.:

SHEET

PEAK LET-THRU CHARACTERISTIC CURVES

LITTELFUSE, INC.

CHICAGO, IL. USA

LLL

01/28/2014

B

2 OF 3

FCC05-JLLS

JLLS 30A - 1200A

- DATA GENERATED IN EXCEL -

1,000

10,000

100,000

1,000,000

1,000

10,000

100,000

AVAILABLE FAULT CURRENT

SYMMETRICAL R.M.S. AMPERES

1200A -

1100A -

1000A -

900A -

BASIS FOR DATA:

TEST VOLTAGE: 600V

TIME CONSTANT/POWER FACTOR:

FUSE CATALOG NUMBER:

DRAWN BY:

DATE:

REVISION:

DRAWING NO.:

SHEET

PEAK LET-THRU CHARACTERISTIC CURVES

LITTELFUSE, INC.

CHICAGO, IL. USA

LLL

01/28/2014

A

3 OF 3

FCC05-JLLS

JLLS 30A - 1200A

Peak Let-Thru Curves