Equivalent & Substitute Parts for AP/ETF-2 Board Mount Fuse

Part Overview

The AP/ETF-2 is a 2 A, 277 V AC board mount fuse manufactured by Eaton - Electronics Division, designed for through-hole radial mounting in vertical orientation. This component is classified as obsolete, necessitating identification of active substitute parts that maintain functional compatibility within specified electrical and mechanical parameters.

The primary reason for identifying substitutes is the obsolete product status of the AP/ETF-2. Active alternatives ensure continued availability for new designs, repairs, and production continuity.

Substiute Parts

AP/ETF-2

Eaton - Electronics DivisionIn Stock: 1148AP/ETF-2 Datasheet

Current PartRFQ

SR-5-2A-AP

Eaton - Electronics DivisionIn Stock: 3606SR-5-2A-AP Datasheet

SimilarRFQ

0034.6818

SCHURTER Inc.In Stock: 31670034.6818 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the AP/ETF-2 is determined by the following critical parameters:

Mandatory Matching Parameters:

• Current Rating: 2 A (exact match required)
• Mounting Type: Through Hole (exact match required)
• Fuse Type: Board Mount, Radial, Can, Vertical (exact match required)
• Response Time: Slow Blow (exact match required)

Voltage Compatibility Criteria: Substitute parts must support the AC voltage requirement of 277 V. Parts rated at lower AC voltages (250 V AC) are not suitable for direct substitution in 277 V AC circuits, as they do not meet the voltage rating specification of the original component.

Identified Substitutes: Based on the provided substitute list, no parts meet all mandatory matching parameters while also satisfying the 277 V AC voltage requirement. Both listed substitutes (SR-5-2A-AP and 0034.6818) are rated at 250 V AC maximum, which is below the 277 V AC requirement of the AP/ETF-2.

Parameter Comparison

Engineering Selection Recommendations

Voltage Rating Constraint: The AP/ETF-2 operates at 277 V AC, which exceeds the maximum AC voltage rating of both listed substitute parts (250 V AC maximum). Direct substitution of SR-5-2A-AP or 0034.6818 in circuits designed for 277 V AC operation is not permissible under standard electrical safety practices, as the substitute parts would operate beyond their rated voltage specification.

Compliance and Certification: Both substitute parts hold active product status with expanded regulatory approvals (CCC, cULus/cURus, KC-MARK/KC, PSE, SEMKO, VDE) compared to the original part (SEMKO, UL). The SR-5-2A-AP and 0034.6818 are RoHS3 compliant and REACH unaffected, providing enhanced environmental compliance.

Mechanical and Thermal Compatibility: Both substitutes maintain identical mounting type, fuse type, package configuration, and response time. However, dimensional variations exist: the substitutes are slightly larger (0.335" diameter vs. 0.329" for the main part), which may affect board layout compatibility. The SR-5-2A-AP operates within a narrower temperature range (-40°C ~ 85°C) compared to the AP/ETF-2 and 0034.6818 (-55°C ~ 125°C).

Electrical Performance Differences: The AP/ETF-2 provides higher breaking capacity (100 A) at rated voltage compared to substitutes (35 A). The melting I²t values differ: AP/ETF-2 (23), SR-5-2A-AP (30), and 0034.6818 (34), indicating different thermal response characteristics.

Frequently Asked Questions (FAQ)

Q: Can SR-5-2A-AP or 0034.6818 be used as direct replacements for AP/ETF-2 in 277 V AC applications?

A: No. The substitute parts are rated for 250 V AC maximum, which is below the 277 V AC requirement of the AP/ETF-2. Using a component beyond its voltage rating violates electrical safety standards and may result in component failure or safety hazards.

Q: What are the key parameters that determine fuse substitution compatibility?

A: Current rating, voltage rating (AC and DC), mounting type, fuse type, package configuration, and response time must match or exceed the original specification. For the AP/ETF-2, the critical parameters are 2 A current, 277 V AC voltage, through-hole mounting, board mount radial can vertical package, and slow-blow response.

Q: Are there dimensional differences between the AP/ETF-2 and the listed substitutes?

A: Yes. The AP/ETF-2 measures 0.329" diameter x 0.303" height, while SR-5-2A-AP measures 0.335" diameter x 0.319" height, and 0034.6818 measures 0.335" diameter x 0.335" height. These dimensional variations may affect PCB footprint compatibility and require verification during design integration.

Q: What is the operating temperature range difference between the main part and substitutes?

A: The AP/ETF-2 and 0034.6818 both operate from -55°C to 125°C. The SR-5-2A-AP operates within a narrower range of -40°C to 85°C, which may be limiting for applications requiring extended low-temperature operation.

Q: How do the breaking capacities compare?

A: The AP/ETF-2 has a breaking capacity of 100 A at rated voltage, while both SR-5-2A-AP and 0034.6818 have breaking capacities of 35 A AC. This represents a significant reduction in fault current handling capability and must be evaluated for the specific application circuit.

Q: What regulatory certifications do the substitute parts hold?

A: SR-5-2A-AP holds CCC, cULus, KC-MARK, PSE, SEMKO, and VDE certifications. The 0034.6818 holds CCC, cURus, KC, PSE/JET, and VDE certifications. Both are RoHS3 compliant and REACH unaffected, providing broader international regulatory coverage than the original AP/ETF-2.

Q: Can 0034.6818 be used in DC applications?

A: The 0034.6818 is rated for 125 V DC, providing dual AC/DC capability. However, this does not address the voltage mismatch issue for 277 V AC applications. The part remains unsuitable for the AP/ETF-2 application due to insufficient AC voltage rating.