Equivalent & Substitute Parts for 5TT 3 Glass Cartridge Fuse

Part Overview

The 5TT 3 is a 3A 250VAC slow-blow glass cartridge fuse manufactured by Bel Fuse Inc., designed for 5mm x 20mm holder applications. This component is classified as obsolete, making identification of active equivalent parts essential for ongoing system support and component procurement. The 5TT 3-R serves as the direct active substitute, maintaining identical electrical and mechanical specifications while offering improved compliance status and significantly higher inventory availability.

Substiute Parts

5TT 3

Bel Fuse Inc.In Stock: 9995TT 3 Datasheet

Current PartRFQ

5TT 3-R

Bel Fuse Inc.In Stock: 1118475TT 3-R Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

The 5TT 3-R is a direct functional equivalent to the 5TT 3. Substitution is valid based on the following matching parameters:

• Current Rating: 3 A (identical)
• Voltage Rating (AC): 250 V (identical)
• Fuse Type: Cartridge, Glass (identical)
• Response Time: Slow Blow (identical)
• Package / Case: 5mm x 20mm (identical)
• Mounting Type: Requires Holder (identical)
• Breaking Capacity @ Rated Voltage: 100A (identical)
• Operating Temperature Range: -55°C ~ 125°C (identical)

The 5TT 3-R maintains all critical electrical and mechanical parameters required for direct substitution in applications originally specified for the 5TT 3.

Parameter Comparison

Engineering Selection Recommendations

The 5TT 3-R is the appropriate selection for new designs and component replacement applications. The obsolete status of the 5TT 3 necessitates transition to the 5TT 3-R, which maintains electrical and mechanical compatibility while offering active product status and ROHS3 compliance. The 5TT 3-R carries equivalent safety certifications (CE, CSA, cULus, PSE) and is manufactured by the same supplier, ensuring continuity in supply chain and performance characteristics.

Minor variations in melting I²t (55.6 versus 68) and DC cold resistance (0.043 versus 0.04 Ohms) fall within acceptable tolerance ranges for slow-blow cartridge fuse applications and do not affect functional substitution.

Frequently Asked Questions (FAQ)

Q: Can the 5TT 3-R directly replace the 5TT 3 in existing applications?

A: Yes. The 5TT 3-R maintains identical current rating (3A), voltage rating (250VAC), response time (slow-blow), and physical dimensions (5mm x 20mm). Both components require the same holder type and operate across the same temperature range (-55°C to 125°C).

Q: What is the difference in melting I²t between the two parts?

A: The 5TT 3 has a melting I²t of 68, while the 5TT 3-R has 55.6. This variation is within acceptable tolerance for slow-blow fuse performance and does not prevent direct substitution.

Q: Are there differences in safety certifications?

A: Both parts carry CE, CSA, and PSE certifications. The 5TT 3-R includes cULus certification in addition to UL. These certifications are equivalent for the intended application.

Q: Why is the 5TT 3 listed as obsolete?

A: The 5TT 3 has been superseded by the 5TT 3-R, which offers improved compliance status (ROHS3 compliant versus non-compliant) and active manufacturing status. The 5TT 3-R is the current production equivalent.

Q: Does packaging differ between the two parts?

A: The 5TT 3 is available in standard packaging, while the 5TT 3-R is supplied in bulk packaging. Both maintain identical component specifications and holder compatibility.