Equivalent & Substitute Parts for 3AP 8-R Glass Cartridge Fuse

Part Overview

The 3AP 8-R is an 8 A, 250 V AC/DC fast-blow glass cartridge fuse manufactured by Bel Fuse Inc. in the 3AB/3AG package format. This component is classified as obsolete, necessitating identification of active equivalent parts for continued system support and procurement. Substitute parts must maintain identical electrical ratings, mechanical dimensions, and approval certifications to ensure direct interchangeability in existing circuit protection applications.

Substiute Parts

3AP 8-R

Bel Fuse Inc.In Stock: 6903AP 8-R Datasheet

Current PartRFQ

0318008.HXP

LittelfuseIn Stock: 8630318008.HXP Datasheet

DirectRFQ

0318008.MXP

Littelfuse Inc.In Stock: 27200318008.MXP Datasheet

DirectRFQ

0318008.VXP

Littelfuse Inc.In Stock: 7750318008.VXP Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 3AP 8-R is determined by strict equivalence across the following parameters:

• Current Rating: 8 A (exact match required)
• Voltage Rating: 250 V AC (exact match required)
• Fuse Type: Cartridge, Glass (exact match required)
• Response Time: Fast Blow (exact match required)
• Package / Case: 3AB, 3AG, 1/4" x 1-1/4" (Axial) (exact match required)
• Breaking Capacity: 200 A (exact match required)
• Mounting Type: Through Hole (exact match required)
• Operating Temperature: -55°C ~ 125°C (exact match required)
• RoHS Compliance: ROHS3 Compliant (exact match required)

All identified substitute parts from Littelfuse Inc. (0318008.HXP, 0318008.MXP, 0318008.VXP) meet these criteria and are classified as active products with current manufacturing status.

Parameter Comparison

Engineering Selection Recommendations

All three Littelfuse substitute parts (0318008.HXP, 0318008.MXP, 0318008.VXP) are direct equivalents to the 3AP 8-R and are suitable for replacement in applications requiring an 8 A, 250 V AC/DC fast-blow glass cartridge fuse in the 3AB/3AG package.

The substitute parts carry active product status from Littelfuse Inc., ensuring ongoing availability and manufacturing support. All substitute parts maintain ROHS3 compliance and carry expanded approval certifications (CE, CSA, KC, PSE, UL) compared to the original part.

Minor dimensional variations exist between the original and substitute parts (0.272" vs. 0.275" diameter; 1.280" vs. 1.288" length), remaining within standard mechanical tolerances for 3AB/3AG cartridge fuses. DC cold resistance and melting I²t values show minor differences that do not affect functional equivalence for circuit protection applications.

Frequently Asked Questions (FAQ)

Q: Can 0318008.HXP, 0318008.MXP, and 0318008.VXP be used interchangeably with the 3AP 8-R?

A: Yes. All three Littelfuse parts meet the electrical and mechanical specifications required for direct substitution. They share identical current ratings (8 A), voltage ratings (250 V AC), fuse type (cartridge, glass), response time (fast blow), package format (3AB/3AG), and breaking capacity (200 A).

Q: What is the difference between the three Littelfuse substitute parts?

A: The three parts (0318008.HXP, 0318008.MXP, 0318008.VXP) are electrically and mechanically identical. Differences in part number suffixes reflect internal Littelfuse manufacturing or packaging designations. All three are functionally equivalent for circuit protection applications.

Q: Are there dimensional differences between the 3AP 8-R and the substitute parts?

A: Minor dimensional variations exist. The 3AP 8-R measures 0.272" diameter x 1.280" length, while the Littelfuse substitutes measure 0.275" diameter x 1.288" length. These variations fall within standard mechanical tolerances for 3AB/3AG cartridge fuses and do not affect mechanical fit or electrical performance in standard through-hole fuse holders.

Q: Do the substitute parts carry the same certifications as the original?

A: The substitute parts carry expanded certifications. The 3AP 8-R holds CE, CSA, cULus, and PSE approvals. The Littelfuse substitutes hold CE, CSA, KC, PSE, and UL approvals, providing broader regulatory coverage.

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

A: The 3AP 8-R has a melting I²t of 184, while the Littelfuse substitutes have a melting I²t of 166. Both values are within the fast-blow fuse classification and maintain the same 8 A current rating and 250 V voltage rating. This difference does not affect functional equivalence for standard circuit protection applications.

Q: Are all substitute parts currently in stock?

A: Inventory status is subject to change. At the time of data collection, 0318008.HXP had 797 units, 0318008.MXP had 2612 units, and 0318008.VXP had 706 units available from original stock.