Bel Fuse Inc. C1S 4.6A 63V Surface Mount Fuse - Equivalent & Substitute Parts

Part Overview

The Bel Fuse Inc. C1S 4.6 is a surface mount board fuse rated for 4.6 amperes at 63 volts AC/DC with slow blow response characteristics. This component is classified as obsolete, necessitating identification of active equivalent parts for new designs and ongoing production requirements. The C1S series has been superseded by the C1T series, which maintains electrical equivalence while offering improved availability and active product support.

Substiute Parts

C1S 3.5

Bel Fuse Inc.In Stock: 1097C1S 3.5 Datasheet

Current PartRFQ

0685T3500-01

Bel Fuse Inc.In Stock: 843410685T3500-01 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

The C1S 4.6 and its substitute 0685T3500-01 (C1T series) are electrically and mechanically equivalent based on the following critical parameters:

• Current Rating: Both rated at 4.6 A
• Voltage Rating: Both rated at 63 V AC and 63 V DC
• Response Characteristic: Both employ slow blow response
• Package: Both use 1206 (3216 Metric) surface mount package
• Breaking Capacity: Both rated at 50 A @ rated voltage
• Operating Temperature: Both operate across -55°C to 125°C
• Compliance: Both are ROHS3 compliant and carry CE and cURus certifications

The primary distinction between these parts is product status and packaging format. The C1S 4.6 is obsolete, while 0685T3500-01 is an active product available in tape and reel packaging with enhanced inventory availability.

Parameter Comparison

Engineering Selection Recommendations

The 0685T3500-01 (C1T series) is the direct active substitute for the obsolete C1S 4.6. Selection of this part is based on:

• Product Status: The C1T series maintains active production status with full manufacturer support, whereas the C1S is obsolete
• Electrical Equivalence: Identical current, voltage, and response characteristics ensure functional compatibility in existing circuit designs
• Compliance Certifications: The C1T adds AEC-Q200 automotive qualification in addition to CE and cURus certifications, providing broader application coverage
• Packaging Availability: Tape and reel packaging of the 0685T3500-01 supports automated assembly processes and high-volume production requirements
• Inventory Availability: Significantly higher stock levels of the C1T variant ensure supply chain continuity

For applications requiring the C1S 4.6, transition to 0685T3500-01 without circuit modification. Both parts are footprint-compatible in 1206 (3216 Metric) surface mount applications.

Frequently Asked Questions (FAQ)

Q: Can 0685T3500-01 directly replace C1S 4.6 in existing designs?

A: Yes. Both parts share identical electrical ratings (4.6 A, 63 V AC/DC), response characteristics (slow blow), and mechanical package (1206 surface mount). No circuit redesign is required.

Q: What is the difference between C1S and C1T series?

A: The C1T series is the active production equivalent of the obsolete C1S series. Both maintain the same electrical and mechanical specifications. The C1T includes AEC-Q200 automotive qualification and is available in tape and reel packaging.

Q: Are there physical dimension differences between these parts?

A: Dimensions are nearly identical. C1S 4.6 measures 0.126" L × 0.062" W × 0.023" H (3.20mm × 1.58mm × 0.58mm). The 0685T3500-01 measures 0.126" L × 0.062" W × 0.025" H (3.20mm × 1.58mm × 0.63mm). The 0.002" height difference does not affect PCB assembly compatibility.

Q: What is the significance of the melting I²t difference?

A: The C1T variant (0685T3500-01) has a melting I²t of 2.28 compared to 1.18 for the C1S. Both values fall within the slow blow response classification. This parameter reflects thermal mass characteristics and does not affect circuit protection function for applications designed around the 4.6 A rating.

Q: Is the DC cold resistance difference significant?

A: The DC cold resistance values are 0.04 Ohms (C1S) and 0.042 Ohms (C1T). This 0.002 Ohm difference is negligible for board-level fuse applications and does not impact circuit performance.

Q: What certifications does 0685T3500-01 carry?

A: The 0685T3500-01 carries AEC-Q200, CE, and cURus certifications. The original C1S carries CE and cURus certifications. Both are ROHS3 compliant and REACH unaffected.

Q: Is tape and reel packaging required for the substitute?

A: The 0685T3500-01 is supplied in tape and reel (TR) format, which is standard for high-volume surface mount assembly. If alternative packaging is required, contact the manufacturer for availability of other packaging options within the C1T series.