Littelfuse 0675.125DRT4P Ceramic Fuse - Equivalent & Substitute Parts

Part Overview

The Littelfuse 0675.125DRT4P is a 125 mA, 250 V AC/DC ceramic cartridge fuse with slow-blow response characteristics, designed for through-hole mounting in axial configuration. This part is classified as obsolete, making identification of equivalent and substitute components essential for ongoing system support and procurement planning. The fuse features a non-standard axial cartridge package with a breaking capacity of 50 A at rated voltage and is compliant with RoHS3 standards.

Substiute Parts

0675.125DRT4P

Littelfuse Inc.In Stock: 9770675.125DRT4P Datasheet

Current PartRFQ

0875.125MRET1P

Littelfuse Inc.In Stock: 9540875.125MRET1P Datasheet

DirectRFQ

0675.125DRT4

Littelfuse Inc.In Stock: 8000675.125DRT4 Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the 0675.125DRT4P is determined by strict equivalence across the following critical parameters:

• Current Rating: 125 mA (exact match required)
• Voltage Rating (AC): 250 V (exact match required)
• Fuse Type: Cartridge, Ceramic (exact match required)
• Response Time: Slow Blow (exact match required)
• Mounting Type: Through Hole (exact match required)
• Breaking Capacity @ Rated Voltage: 50 A (exact match required)

Two substitute parts meet these criteria:

1. 0875.125MRET1P (Direct Manufacturer Substitute) - Active product status with enhanced specifications
2. 0675.125DRT4 (Parametric Equivalent) - Same series with active product status

Parameter Comparison

Engineering Selection Recommendations

For new designs and active procurement: The 0875.125MRET1P is the preferred substitute. This part carries active product status, expanded operating temperature range (-55°C to 125°C), and cULus certification. The dimensional variation (0.142" Dia x 0.394" L versus 0.154" Dia x 0.433" L) and increased melting I²t value (0.0072 versus 0.0036) must be evaluated for mechanical fit and thermal response compatibility within the target application.

For direct dimensional and electrical equivalence: The 0675.125DRT4 maintains identical dimensions and DC cold resistance to the main part while offering active product status. However, this part does not meet RoHS3 compliance, which may restrict use in regulated applications.

Compliance considerations: The obsolete 0675.125DRT4P and active 0675.125DRT4 both carry CSA and UL certifications. The 0875.125MRET1P carries cULus certification, which encompasses both CSA and UL standards. All three parts are classified under HTSUS code 8536.10.0040 and carry EAR99 ECCN designation.

Frequently Asked Questions (FAQ)

Q: Can the 0875.125MRET1P be used as a direct replacement for the 0675.125DRT4P?

A: The 0875.125MRET1P meets all critical electrical parameters (125 mA, 250 V AC, 50 A breaking capacity, slow-blow response). However, dimensional differences exist: the substitute is 0.142" diameter x 0.394" length compared to 0.154" diameter x 0.433" length. Physical fit within the fuse holder must be confirmed before substitution.

Q: What is the difference between the 0875.125MRET1P and 0675.125DRT4?

A: Both are active products with identical electrical ratings. The 0875.125MRET1P offers expanded operating temperature range (-55°C to 125°C) and cULus certification. The 0675.125DRT4 maintains the original dimensions and DC cold resistance but does not meet RoHS3 compliance. The 0875.125MRET1P has a higher melting I²t value (0.0072 versus 0.0036), affecting thermal response characteristics.

Q: Why is the 0675.125DRT4P listed as obsolete?

A: The 0675.125DRT4P is classified as obsolete by the manufacturer. The active equivalent 0675.125DRT4 is available as a direct parametric replacement, while the 0875.125MRET1P represents an enhanced alternative with improved specifications and certifications.

Q: Does packaging format affect substitution?

A: The main part 0675.125DRT4P packaging is not specified. The 0875.125MRET1P is supplied in Tape & Reel (TR) format. Packaging format does not affect electrical or mechanical compatibility; however, procurement and handling procedures may differ.

Q: Are there RoHS compliance implications for substitution?

A: The 0675.125DRT4P and 0875.125MRET1P are both RoHS3 compliant. The 0675.125DRT4 is RoHS non-compliant. For applications requiring RoHS compliance, either the main part or the 0875.125MRET1P must be selected.