3SB 6 Equivalent & Substitute Parts

Part Overview

The 3SB 6 is a 6 A, 250 V AC/DC glass cartridge fuse manufactured by Bel Fuse Inc. designed for circuit protection in industrial and commercial applications. This fuse features a slow-blow response characteristic and requires a 3AB or 3AG holder for installation. The part is currently listed as obsolete, making equivalent substitute parts necessary for ongoing system maintenance and new designs requiring this specification.

Substiute Parts

3SB 6

Bel Fuse Inc.In Stock: 8203SB 6 Datasheet

Current PartRFQ

3SB 6-R

Bel Fuse Inc.In Stock: 39303SB 6-R Datasheet

DirectRFQ

TSA-6A

OptiFuseIn Stock: 4746TSA-6A Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 3SB 6 are qualified based on strict electrical and mechanical parameter matching:

Critical Matching Parameters:

• Current Rating: 6 A (exact match required)
• Voltage Rating: 250 V AC (exact match required)
• Fuse Type: Cartridge, Glass (exact match required)
• Response Time: Slow Blow (exact match required)
• Package / Case: 3AB, 3AG, 1/4" x 1-1/4" (exact match required)
• Physical Dimensions: 0.250" Dia x 1.252" L (exact match required)
• Breaking Capacity: 200 A (exact match required)
• Operating Temperature: -55°C ~ 125°C (exact match required)

Both substitute parts listed below meet all critical parameters and are mechanically and electrically interchangeable with the 3SB 6.

Parameter Comparison

Engineering Selection Recommendations

3SB 6-R (Bel Fuse Inc.): This part is the direct manufacturer replacement for the obsolete 3SB 6. It maintains identical electrical and mechanical specifications while offering active product status and ROHS3 compliance. The 3SB 6-R carries CE, CSA, cULus, and PSE certifications and is recommended as the primary substitute for applications requiring continuity with the original Bel Fuse product line.

TSA-6A (OptiFuse): This part provides parametric equivalence across all critical electrical and mechanical parameters. The TSA-6A is an active product with ROHS3 compliance and cULus/UL 248 certifications. The higher melting I²t value (857.2 versus 286) indicates a different thermal response profile; however, both parts maintain the slow-blow characteristic and identical current/voltage ratings. The TSA-6A is suitable for applications where cross-manufacturer substitution is acceptable.

Frequently Asked Questions (FAQ)

Q: Can the 3SB 6-R be used as a direct replacement for the 3SB 6?

A: Yes. The 3SB 6-R is electrically and mechanically identical to the 3SB 6, with matching current rating (6 A), voltage rating (250 V AC), fuse type (cartridge, glass), response time (slow blow), package dimensions (3AB, 3AG, 1/4" x 1-1/4"), and breaking capacity (200 A). The primary difference is product status: the 3SB 6-R is active while the 3SB 6 is obsolete.

Q: What is the difference between the 3SB 6-R and TSA-6A?

A: Both parts are electrically and mechanically equivalent across all critical parameters: 6 A current rating, 250 V AC voltage, slow-blow response, cartridge glass fuse type, and 3AB/3AG package compatibility. The TSA-6A is manufactured by OptiFuse rather than Bel Fuse Inc. The melting I²t differs (857.2 for TSA-6A versus 286 for 3SB 6-R), reflecting different thermal characteristics within the slow-blow classification. Both parts carry appropriate safety certifications.

Q: Are these fuses compatible with existing 3AB and 3AG holders?

A: Yes. All three parts share identical physical dimensions (0.250" Dia x 1.252" L) and are designed for 3AB and 3AG holder compatibility. No holder modifications or replacements are required when substituting between these parts.

Q: What certifications do the substitute parts carry?

A: The 3SB 6-R carries CE, CSA, cULus, and PSE certifications. The TSA-6A carries cULus and UL 248 certifications. Both parts meet ROHS3 compliance requirements.

Q: Can I use the TSA-6A in applications originally designed for the 3SB 6?

A: Yes, provided the application does not have specific manufacturer or certification requirements that exclude OptiFuse products. The TSA-6A meets all electrical and mechanical specifications for the 3SB 6 and carries appropriate safety certifications (cULus, UL 248).