Mersen TR300R Class RK5 Time-Delay Current Limiting Fuse – 300A – 250VAC/250VDC – Tri-Onic® Series

The Mersen TR300R is a Tri-Onic® Class RK5 time-delay fuse engineered for reliable overcurrent and short-circuit protection in industrial and commercial electrical systems. Rated at 300 Amps, this current-limiting fuse is designed to safely withstand motor starting currents and transformer inrush conditions while providing dependable protection for downstream equipment. With voltage ratings up to 250VAC and 250VDC, the TR300R is widely used in feeder circuits, branch circuits, service entrance equipment, motors, and transformers requiring coordinated time-delay protection.

Voltage and Rating

• Current Rating: 300 Amps
• Voltage Rating: 250VAC / 250VDC
• Frequency: 50/60 Hz
• Fuse Class: RK5
• Fuse Type: Time-Delay, Current-Limiting

Key Specifications

• Product Type: Industrial Fuse
• Series: Tri-Onic® TR-R
• Part Number: TR300R
• Manufacturer: Mersen / Ferraz Shawmut
• Mounting Style: Blade
• Time-Delay Feature: Yes
• Current Limiting: Yes

Technical Specifications

• Protection Type: Overcurrent and Short-Circuit Protection
• Suitable For: Motors, Transformers, Feeders, Service Entrance Equipment, and Branch Circuits
• Inrush Current Handling: Designed to withstand motor starting and transformer energizing currents
• Construction Features: Time-Delay Operation, High Interrupting Current-Limiting Design
• Application: Industrial and Commercial Power Distribution Systems

Standards and Approvals

• Rated Voltage AC (UL): 250VAC
• Rated Voltage DC (UL): 250VDC
• Fuse Classification: Class RK5

Product Data

• Manufacturer: Mersen / Ferraz Shawmut
• Series: Tri-Onic® TR-R
• Part Number: TR300R
• EAN/UPC: 782001748135

Applications

• Motor Protection
• Transformer Protection
• Service Entrance Equipment
• Feeder Circuit Protection
• Branch Circuit Protection
• Industrial Power Distribution Systems
• Commercial Electrical Installations
• Motor Control Centers
• Heavy-Duty Electrical Infrastructure
• General Purpose Overcurrent Protection Systems

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You may return items within 30 days of delivery for a refund.

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