Cooper Bussmann ECSR70 70A 600V Class RK5 Fuse

Product Description

The COOPER BUSSMANN ECSR70 is a time-delay, current-limiting, dual-element fuse rated at 70 amps and 600 volts. It belongs to the Class RK5 category and is designed to provide superior overload and cycling protection in electrical distribution systems. The dual-element construction separates the overload and short-circuit sensing functions, allowing the fuse to withstand temporary inrush currents without nuisance opening while still responding quickly to sustained overloads and faults. With an interrupting rating of 200 kAIC, it is suitable for high-fault-current environments. Licensed electricians and electrical contractors are the primary installers of this fuse type.

The ECSR70 is used in motor branch circuits, HVAC equipment disconnects, and general-purpose electrical panels where time-delay performance is required to accommodate motor starting inrush. Its 10-second delay at 500 percent of rated current allows motors and other inductive loads to start without blowing the fuse under normal conditions. It fits standard Class RK5 fuse holders and fusible disconnect switches rated for blade-end termination. Applications span residential, light commercial, and commercial electrical installations.

Key Features

• Dual-element design provides independent overload and short-circuit protection in a single fuse body
• Time-delay rating of 10 seconds at 500 percent of rated current accommodates motor starting inrush
• 200 kAIC interrupting rating for use in high-fault-current applications
• Class RK5 classification fits standard RK5-rated fuse holders and disconnects
• Non-indicating construction with blade-end-by-blade-end termination
• 600-volt rating covers the majority of single-phase and three-phase commercial and industrial distribution voltages

Compatibility

Designed as an OEM-style replacement for Class RK5 time-delay dual-element fuses in standard blade-end fuse holders and fusible disconnect switches rated at 600 volts and 70 amps.

Installation Notes

Installation and replacement of this fuse must be performed by a licensed electrician in accordance with the National Electrical Code (NEC) and all applicable local codes. De-energize and lock out the circuit at the upstream overcurrent device before servicing the fuse holder or disconnect. Verify that the replacement fuse amperage, voltage rating, and Class designation match the requirements of the circuit and the fuse holder. Do not install a fuse with a higher amperage rating than the circuit is designed to carry.

Technical Specifications

• Amperage Rating: 70 amps
• Voltage Rating: 600 volts
• Fuse Class: Class RK5
• Fuse Type: Time-delay, current-limiting, dual element
• Interrupting Rating: 200 kAIC
• Time-Delay Performance: 10 seconds at 500 percent of rated current
• Termination Style: Blade end x blade end
• Indicating: Non-indicating
• UPC: 782634508403

Standard Information

• Brand: COOPER BUSSMANN
• Manufacturer Part Number: ECSR70