Overview
The Marathon F30A3B is a 3-pole Class H fuse block engineered for industrial electrical distribution and panel mounting applications. Rated at 30A 250V, this fuse holder accommodates standard Class H fuses and delivers consistent, reliable protection in manufacturing, HVAC, motor control, and machinery control cabinets. The screw terminal design allows secure wire connections from 10–22 AWG copper wire.
Key Features
- 3-Pole Configuration: Designed for 3-pole, 30A, 250V Class H fuse applications
- Class H Fuse Compatibility: Accommodates all Class H 250V power fuses
- Screw Terminal Connections: Supports both direct wire and spade/ring terminal installation
- Thermoplastic Insulator Base: Thermoplastic insulator base with tin-plated copper alloy clips
- Standard Fuse Size: Holds fuse size 9/16-inch diameter x 2-inch
- Panel Mount Design: Compact, drop-in fit for standard distribution enclosures
Technical Specifications
- Voltage Rating: 250V DC/AC
- Current Rating: 30A
- Poles: 3
- Fuse Size: 9/16″ diameter × 2″
- Terminal Type: Screw connectors
- Wire Size Range: 10–22 AWG copper
- Mounting: Panel mount
- Insulation Material: Thermoplastic
- Contact Material: Tin-plated copper alloy
- Fuse Class: Class H
- RoHS Compliant: Yes
- Weight: 0.25 lbs
Typical Applications
The Marathon F30A3B is widely used in:
- Industrial motor control centers and variable frequency drive enclosures
- HVAC equipment and process heating systems
- Machinery control panels and automation cabinets
- Electrical distribution boards and switchgear
- Power supply circuits requiring Class H fuse protection
Compatibility & Replacements
Compatible With
- All Class H 250V and 600V power fuses
- Standard panel-mount electrical enclosures
- Industrial control cabinets (UL/CSA-rated)
- Motor control centers and distribution equipment
Replaces / Drop-In Replacement For
The Marathon F30A3B directly replaces other 3-pole 30A 250V Class H fuse blocks with matching terminal types and footprints. Verify mounting dimensions and terminal configuration with your system integrator before ordering to ensure drop-in compatibility.
Works With
- Marathon Special Products fuse blocks and holders (F30A series)
- Class H industrial-rated fuses (A2Y, CRN, NLN, NON, NRN, OT, OTN, RLN, RF designations)
- Standard UL/CSA-certified industrial electrical systems
- Screw terminal wire connections (10–22 AWG copper)
















