0713 BU-SB13686 Page 1 of 3 Data Sheet # 1003
Low-Peak™ 250V Class RK1
LPN-RK — 250Vac/dc, 1⁄10-60A, Dual Element, Time-Delay Fuses
Description: Ultimate protection Class RK1 dual element,
current-limiting, time-delay fuses available with optional open
fuse indication. Time-delay – 10 seconds (minimum) at 500%
of rated current (8 seconds for 0-30A sizes).
Catalog Symbol: LPN-RK(amp)SP (non-indicating)
LPN-RK(amp)SPI (indicating)
Ratings:
Volts — 250Vac, 125Vdc
Amps — 1⁄10-60A
IR — 300kA Vac RMS Sym.
— 100kA Vdc
Agency Information:
CE, UL Listed, Guide JDDZ, File E4273
CSA Certified, Class 1422-02, File 53787,
Class RK1 per CSA C22.2, No. 248.12
Catalog Numbers (amps) Non-indicating Fuses
LPN-RK-1⁄10SP LPN-RK-2SP LPN-RK-9SP
LPN-RK-15⁄100SP LPN-RK-21⁄4SP LPN-RK-10SP
LPN-RK-2⁄10SP LPN-RK-21⁄2SP LPN-RK-12SP
LPN-RK-3⁄10SP LPN-RK-28⁄10SP LPN-RK-15SP
LPN-RK-4⁄10SP LPN-RK-3SP LPN-RK-171⁄2SP
LPN-RK-1⁄2SP LPN-RK-32⁄10SP LPN-RK-20SP
LPN-RK-6⁄10SP LPN-RK-31⁄2SP LPN-RK-25SP
LPN-RK-8⁄10SP LPN-RK-4SP LPN-RK-30SP
LPN-RK-1SP LPN-RK-41⁄2SP LPN-RK-35SP*
LPN-RK-11⁄8SP LPN-RK-5SP LPN-RK-40SP*
LPN-RK-11⁄4SP LPN-RK-56⁄10SP LPN-RK-45SP*
LPN-RK-14⁄10SP LPN-RK-6SP LPN-RK-50SP*
LPN-RK-16⁄10SP LPN-RK-61⁄4SP LPN-RK-60SP*
LPN-RK-18⁄10SP LPN-RK-8SP
* Open fuse indication available by inserting the suffix “I,” e.g. LPN-RK-50SPI.
Requires 75Vac minimum voltage.
Carton Quantity and Weight
Amp Rating Carton Qty.
0–30 10
35–60 10
Dimensions – in
Features:
• Industry’s only UL Listed and CSA Certified fuse with a
300kA Vac interrupting rating that exceeds requirements for
virtually all applications
• Current-limitation for maximum short-circuit protection
• Easy selective coordination with all Low-Peak fuses using
simple 2:1 ampacity ratio
• “No damage” Type “2” protection for IEC and NEMA
starters when properly sized
• High inrush current motor protection
• Time-delay permits 130% FLA sizing for back-up motor
protection
• Protection against single-phase motor damage
• Low watt loss power consumption
• Electrically isolated end caps for added safety
Recommended Fuse Blocks
Fuse Amps 1-Pole 2-Pole 3-Pole
0-30 H25030-1 H25030-2 H25030-3
R25030-1 R25030-2 R25030-3
35-60 H25060-1 H25060-2 H25060-3
R25060-1 R25060-2 R25060-3
For additional information on the 250 volt fuse blocks, see
Data Sheets # 1110 (R250), # 1112 (H250).
Fuse Reducers For Class R Fuses
Equipment Desired Fuse Catalog Numbers
Fuse Clips (Case) Size (Pairs) 250V
60A 30A NO.263-R
100A 30A NO.213-R
60A NO.216-R
200A 60A NO.226-R
For additional information on Class R fuse reducers, see
Data Sheet 1118.
0.56" (±0.008)
2"
(± 0.31)
1/10 to 30A
3"
35 to 60A
0.81" (±0.008)
(± 0.31)
Available with easyID™
open fuse indication
0713 BU-SB13686 Page 2 of 3 Data Sheet # 1003
Low-Peak™ 250V Class RK1
Time-Current Curves - Average Melt
1⁄10 to 12 Amps
.1
.2
.15
.3
.4
.6 .5
.8
11.25
1.6 2
2.5
3.2
4
56.25
8
10
12
AMP RATING
300
100
10
1
.1
.01
.1
1
10
100
1,000
RMS SYMMETRICAL CURRENT IN AMPS
TIME IN SECONDS
LPN-RK — 250Vac/dc, 1⁄10-60A, Dual Element, Time-Delay Fuses
0713 BU-SB13686 Page 3 of 3 Data Sheet # 1003
Low-Peak™ 250V Class RK1
The only controlled copy of this Data Sheet is the electronic read-only version located on the Cooper Bussmann Network Drive. All other copies of this document are by definition uncontrolled. This bulletin is
intended to clearly present comprehensive product data and provide technical information that will help the end user with design applications. Cooper Bussmann reserves the right, without notice, to change
design or construction of any products and to discontinue or limit distribution of any products. Cooper 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.
Current-Limitation Curves
Time-Current Curves - Average Melt
15 to 60 Amps
20A
60A
30A
AMP RATING
15A
RMS SYMMETRICAL CURRENT IN AMPS
20
100
1,000
10,000
TIME IN SECONDS
300
100
10
1
.1
.01
B
60A
30A
AMP RATING
INSTANTANEOUS PEAK LET-THROUGH CURRENT IN AMPERES
PROSPECTIVE SHORT-CIRCUIT CURRENT - SYMMETRICAL RMS AMPS
400,000
9,000
8,000
7,000
6,000
6,000
300,000
200,000
100,000
5,000
4,000
4,000
90,000
3,000
2,000
1,000
3,000
80,000
70,000
60,000
50,000
60,000
200,000
20,000
2,000
40,000
100,000
10,000
1,000
30,000
80,000
40,000
8,000
30,000
20,000
10,000
300,000
A
LPN-RK — 250Vac/dc, 1⁄10-60A, Dual Element, Time-Delay Fuses
The only controlled copy of this Data Sheet is the electronic read-only version located on the Cooper Bussmann Network Drive. All other copies of this document are by definition uncontrolled. This bulletin is
intended to clearly present comprehensive product data and provide technical information that will help the end user with design applications. Cooper Bussmann reserves the right, without notice, to change
design or construction of any products and to discontinue or limit distribution of any products. Cooper 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.
Current-Limiting Effects
Prosp. Let-Through Current
S.C.C. (Apparent RMS Symmetrical Vs. Fuse Rating)
— 30A 60A
1000 1000 1000
2000 1000 1000
3000 1000 1000
5000 1000 2000
10,000 1000 2000
15,000 1000 2000
20,000 1000 3000
25,000 1000 3000
30,000 2000 3000
35,000 2000 3000
40,000 2000 3000
50,000 2000 3000
60,000 2000 3000
70,000 2000 3000
80,000 2000 4000
90,000 2000 4000
100,000 2000 4000
150,000 2000 4000
200,000 3000 5000
250,000 3000 5000
300,000 3000 6000
