Littelfuse MICRO™ 274 0274.125V Fuse Board Mount Equivalent & Substitute Parts

Part Overview

The Littelfuse 0274.125V is a 125 mA, 125 V AC/DC board mount fuse with fast blow response time, designed for through-hole radial mounting in vertical orientation. This component is classified as Active product status with full compliance to RoHS3, REACH, and international approval agencies including CSA, QPL, and UL. Equivalent and substitute parts are identified when identical electrical ratings and mechanical compatibility are maintained across the allowed parameter set for this fuse category.

Substiute Parts

0274.125V

Littelfuse Inc.In Stock: 12110274.125V Datasheet

Current PartRFQ

0273.125H

Littelfuse Inc.In Stock: 9720273.125H Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 0274.125V is determined by strict equivalence across the following critical parameters:

• Current Rating: 125 mA (exact match required)
• Voltage Rating: 125 V AC and 125 V DC (exact match required)
• Response Time: Fast Blow (exact match required)
• Mounting Type: Through Hole (exact match required)
• Package / Case: Radial, Can, Vertical (exact match required)
• Breaking Capacity: 10 kA (exact match required)
• Melting I²t: 0.000961 (exact match required)
• DC Cold Resistance: 1 Ohm (exact match required)
• Approval Agencies: CSA, QPL, UL (exact match required)
• RoHS and REACH Compliance: ROHS3 Compliant, REACH Unaffected (exact match required)

The Littelfuse 0273.125H meets all substitution criteria and is classified as a parametric equivalent within the MICRO™ series family.

Parameter Comparison

Engineering Selection Recommendations

Both the 0274.125V and 0273.125H are Active product status components manufactured by Littelfuse Inc. and carry identical electrical and mechanical specifications. Selection between these parts may be based on inventory availability or supply chain considerations. Both components maintain full compliance with CSA, QPL, and UL approval agencies, and both are ROHS3 Compliant and REACH Unaffected, meeting current regulatory requirements for electronic component deployment.

Frequently Asked Questions (FAQ)

Q: Can the 0273.125H replace the 0274.125V in existing designs? A: Yes. The 0273.125H is a parametric equivalent with identical current rating (125 mA), voltage ratings (125 V AC/DC), response time (Fast Blow), mounting type (Through Hole), package configuration (Radial, Can, Vertical), breaking capacity (10 kA), and all electrical characteristics including DC cold resistance and melting I²t.

Q: Are there differences in operating temperature between these parts? A: The 0274.125V does not specify an operating temperature range in the provided data. The 0273.125H specifies -55°C ~ 85°C. This difference does not affect substitution eligibility based on the allowed parameter set for this fuse category.

Q: Do both parts have the same physical dimensions? A: Yes. Both the 0274.125V and 0273.125H share identical dimensions of 0.250" Dia x 0.350" H (6.35 mm x 8.89 mm) and are configured for radial, can-style, vertical through-hole mounting.

Q: Are approval certifications identical? A: Yes. Both parts carry CSA, QPL, and UL approvals, and both are ROHS3 Compliant and REACH Unaffected.

Q: What is the melting I²t specification and why is it important? A: The melting I²t value of 0.000961 defines the thermal energy required to melt the fuse element. Identical I²t values between substitute parts ensure equivalent protection characteristics and response behavior in the circuit.