ECSR
Class RK5 600Vac, 70 to 600A
Dual-Element, Time-Delay Fuses
Form No. ESCR 70-600
Page 1 of 2
Data Sheet #1318
07-10-07
BU-SB07255
Catalog Symbol: ECSR
Dual-Element, Time-Delay – 10 seconds (minimum) at 500%
rated current
Current-Limiting
Volts: 600Vac (or less)
Amps: 65 to 600A
IR: 200kA RMS Sym.
Agency Information: CE, UL. Listed, Std. 248-12, Class
RK5, Guide JDDZ, File E162363 CSA Certified, HRCI-R
C22.2 No. 248.12, Class 1422-01, File 53787
Features
• Provides motor overload, ground fault and short-circuit
protection. When used in circuits subject to surge
currents such as those caused by motors, transformers
and other inductive components, these fuses can be
sized close to full-load Amps to give maximum
overcurrent protection.
• The time-delay feature makes it possible to use fuse
Amp ratings, which are much smaller than those of
non-time-delay fuses. Considerable cost saving occurs
by permitting the use of smaller size switches, panels
and fuses themselves.
• Provides a good degree of short-circuit protection
(greater current-limitation) to help protect downstream
components from high fault currents.
• Gives motor running back-up protection to motors
without extra costs.
• Helps protect motors against burnout from overloads
and single phasing when sized properly.
Dimensions (inches)
Carton Quantity and Weight
Carton Weight per Carton
Amps Quantity lbs kg
65–100 1 0.54 0.24
101–200 1 1.22 0.54
201–400 1 3.00 1.36
401–600 1 5.00 2.27
Class R Fuse Blocks (600V) Catalog Data
(Clip Retaining Spring Standard, Suffix “R”)
Terminal Type (Suffix No.)
Basic Box Lug w/
Catalog — Reinforced Clip
Amps Poles Number CU only
70 1 R60100-1 CR COR
to 2 R60100-2 CR COR
100 3 R60100-3 CR COR
to 200 1 R60200-1 CR —
to 400 1 R60400-1 CR —
to 600 1 R60600-1 CR —
• Simplifies and improves blackout prevention (selective
coordination ratios).
• Dual-element fuses can be applied in circuits subject to
temporary motor overloads and surge currents to
provide both high-performance, short-circuit and
overload protection.
Catalog Numbers (amps)
ECSR70 ECSR110 ECSR225 ECSR450
ECSR75 ECSR125 ECSR250 ECSR500
ECSR80 ECSR150 ECSR300 ECSR600
ECSR90 ECSR175 ECSR350
ECSR100 ECSR200 ECSR400
ECSR
Class RK5 600Vac, 70 to 600A
Dual-Element, Time-Delay Fuses
Form No. ESCR 70-600
Page 2 of 2
Data Sheet #1318
07-10-07
BU-SB07255
Current Limitation Curves Time-Current Characteristic Curves– Average
Melt
The only controlled copy of this document is the electronic read-only version maintained by Cooper Bussmann. 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, with-
out 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
ECSR Apparent RMS Symmetrical Let-Through Current
Prosp.
SCC 30A 60A 100A 200A 400A 600A
5000 1400 2000 2900 3950 5000 5000
10,000 1850 2650 3600 5100 8550 10,000
15,000 2200 3200 4100 5950 9750 13,700
20,000 2450 3550 4500 6600 10,700 15,000
25,000 2700 3900 4850 7150 11,500 16,100
30,000 2900 4280 5150 7650 12,200 17,050
35,000 3100 4400 5400 8100 12,800 17,900
40,000 3300 4760 5600 8500 13,400 18,700
50,000 3550 5150 6050 9250 14,400 20,050
60,000 3800 5500 6400 9850 15,250 21,250
80,000 4300 6100 7000 10,950 16,750 23,300
100,000 4500 6600 7550 11,900 18,000 25,000
150,000 5200 8000 8600 13,800 20,550 28,450
200,000 5800 8500 9400 15,350 22,550 31,200
Fuse Reducers For Class R Fuses
Equipment Desired Fuse Catalog Number
Fuse Clips (Case) Size (Pairs) 600V
200A 100A No. 2621-R
400A 100A No. 2641-R
200A No. 642-R
100A No. 2661-R
600A 200A No. 2662-R
400A No. 2664-R*
*Single reducer only (pair not required).
