Mars ecsr90 Time-delay Fuse 90A 600V Class RK5

Product Description

The MARS ecsr90 is a dual-element, time-delay, current-limiting fuse rated at 90 amps and 600 volts. It belongs to the Class RK5 designation, offering superior overload and cycling performance suited to motor and transformer branch-circuit protection. The dual-element design provides a 10-second time delay at 500 percent of rated current, allowing motors to start without nuisance opens while still delivering fast response to short-circuit faults. Interrupting capacity is rated at 200 kAIC. Blade end to blade end termination fits standard fusible disconnect hardware. Licensed electricians and industrial maintenance techs are the primary installers.

This fuse is appropriate for residential and light commercial electrical panels, motor control centers, and fusible disconnect switches where Class RK5 time-delay protection is specified. It is commonly installed on HVAC compressor circuits, pump motors, and transformer primaries where inrush current would otherwise open a standard fuse. The non-indicating, blade-end configuration fits directly into holders designed for Class RK5 cartridge fuses up to 600 volts.

Key Features

• 90-amp continuous current rating at 600 volts AC
• Dual-element time-delay design: 10-second hold at 500 percent inrush
• 200 kAIC interrupting rating for high-fault-current environments
• Class RK5 current-limiting performance
• Blade end to blade end termination for standard fusible disconnect holders
• CE Marked for compliance in applicable installations

Compatibility

Designed as an OEM-style replacement Class RK5 time-delay fuse for use in standard 600-volt fusible disconnect switches and motor branch-circuit protection applications.

Installation Notes

Installation must be performed by a licensed electrician in accordance with the National Electrical Code (NEC). Always de-energize and lock out the disconnect or panel before removing or inserting fuses. Verify that the fuse holder is rated for Class RK5 cartridge fuses at 600 volts and 90 amps before installation. Do not substitute a higher-amperage fuse to address nuisance openings; diagnose the underlying load or wiring condition instead.