Bussmann FRS-R Fusetron Class RK5 Time-Delay Fuse

Bussmann FRS-R-3/10 Fusetron Class RK5 Time-Delay Fuse

The Bussmann FRS-R-3/10 Fusetron is a dual-element, current-limiting time-delay fuse rated 3/10A, engineered for Class RK5 applications requiring dependable motor and circuit protection. Rated 600 Vac / 300 Vdc with a ferrule end x ferrule end connection, this fuse pairs a 200 kAIC interrupt rating at 600 Vac (20 kAIC at 300 Vdc) with a 10s at 500% response time to ride through harmless overloads while clearing true faults quickly. It is built for combination starters, motor control centers, machinery disconnects, and power panelboards where reliable, code-compliant overcurrent protection is required.

Key Features

• Amperage Rating: 3/10A for precise low-current circuit protection.
• Class RK5 Construction: Current-limiting, time-delay fuse design suited to motor and branch-circuit applications.
• Dual-Element Design: Two internal elements let the fuse absorb temporary overloads such as motor inrush without nuisance opening.
• Ferrule End x Ferrule End Connection: Simplifies installation into standard fuse holders and disconnect switches.
• Voltage Rating: 600 Vac, 300 Vdc for use across AC and DC electrical systems.
• Interrupt Rating: 200 kAIC at 600 Vac and 20 kAIC at 300 Vdc for high fault-current withstand capability.
• Response Time: 10s at 500% overload, delivering true time-delay performance that rides through motor inrush.
• Non-Indicating Design: Standard fuse body without a blown-fuse indicator window.

Technical Specifications

• Amperage Rating: 3/10A
• Application: Combination starters, motor control centers, machinery disconnects, power panelboards
• Class: Class RK5
• Connection: Ferrule end X ferrule end
• Fuse Indicator: Non Indicating
• Interrupt Rating: 200 kAIC at 600 Vac, 20 kAIC at 300 Vdc
• Number Of Elements: Dual
• Packaging Type: Standard
• Response Time: 10s at 500%
• Voltage Rating: 600 Vac, 300 Vdc
• Product Type: Current-limiting, time delay
• Product Length: .81 IN
• Product Details: Current-limiting, time delay
• Product Diameter: .81 IN
• Product Height: 5 IN
• Product Weight: .15 LB
• Product Width: .81 IN

Typical Applications

• Combination Starters
• Motor Control Centers
• Machinery Disconnects
• Power Panelboards
• Industrial and Commercial Overcurrent Protection

Why Bussmann?

Bussmann engineers the FRS-R Fusetron series for demanding motor control and branch-circuit environments, backing the 3/10A Class RK5 fuse with a 200 kAIC interrupt rating and a proven dual-element time-delay design. This construction helps electricians and facility teams protect combination starters, motor control centers, and panelboards from both overloads and short circuits with confidence in reliable, code-compliant performance.