Equivalent & Substitute Parts for AP/ETF-2.5

Part Overview

The AP/ETF-2.5 is a board mount fuse rated at 2.5 A, 277 V AC, with slow blow response characteristics and radial, can-style vertical mounting. Manufactured by Eaton - Electronics Division, this component is classified as obsolete. Due to its obsolete product status, identifying equivalent substitute parts is necessary for ongoing system maintenance, repair, and new design implementations where this specification remains applicable.

Key Parameters

Parameter	Value
Current Rating	2.5 A
Voltage Rating (AC)	277 V
Response Time	Slow Blow
Mounting Type	Through Hole
Package Style	Radial, Can, Vertical
Breaking Capacity	100 A @ Rated Voltage
Operating Temperature Range	-55°C to 125°C
DC Cold Resistance	0.026 Ohms

Substitute Part Grouping Explanation

Substitution of the AP/ETF-2.5 is determined by the following critical parameters:

Current Rating: The substitute must maintain 2.5 A current rating to ensure proper circuit protection.

Mounting Configuration: Through hole radial, can-style vertical mounting is required for mechanical compatibility with existing board layouts.

Response Characteristic: Slow blow response time must be preserved to match the original protection profile.

Voltage Rating: The substitute voltage rating must be equal to or greater than the application voltage. The AP/ETF-2.5 operates at 277 V AC; substitutes rated at lower voltages (such as 250 V AC) may be used only in applications where the actual circuit voltage does not exceed the substitute's rating.

Physical Dimensions: Package dimensions must accommodate the existing through-hole footprint.

The identified substitute SR-5-2.5A-AP meets the current rating, mounting type, response time, and package style requirements. However, its voltage rating of 250 V AC is lower than the original 277 V AC specification.

Parameter Comparison

Parameter	AP/ETF-2.5 (Main Part)	SR-5-2.5A-AP (Substitute)
Manufacturer	Eaton - Electronics Division	Eaton - Electronics Division
Current Rating (Amps)	2.5 A	2.5 A
Voltage Rating - AC	277 V	250 V
Response Time	Slow Blow	Slow Blow
Mounting Type	Through Hole	Through Hole
Fuse Type	Board Mount (Cartridge Style Excluded)	Board Mount (Cartridge Style Excluded)
Package / Case	Radial, Can, Vertical	Radial, Can, Vertical
Breaking Capacity @ Rated Voltage	100 A	35 A
Melting I²t	37	45
DC Cold Resistance	0.026 Ohms	0.024 Ohms
Operating Temperature Range	-55°C to 125°C	-40°C to 85°C
Product Status	Obsolete	Active
Approval Agencies	SEMKO, UL	CCC, cULus, KC-MARK, PSE, SEMKO, VDE

Engineering Selection Recommendations

The SR-5-2.5A-AP serves as an active substitute for the obsolete AP/ETF-2.5 based on matching current rating, mounting configuration, response time, and package style. Both components are manufactured by Eaton - Electronics Division and share SEMKO approval certification.

Voltage Rating Consideration: The substitute operates at 250 V AC, which is 27 V lower than the original 277 V AC rating. Selection of this substitute is appropriate only for applications where the actual circuit voltage does not exceed 250 V AC.

Breaking Capacity: The substitute has a breaking capacity of 35 A compared to the original 100 A. This represents a reduced fault current handling capability and must be evaluated against the specific circuit requirements.

Temperature Range: The substitute operates across -40°C to 85°C, which is narrower than the original -55°C to 125°C range. Applications requiring operation outside the substitute's temperature limits require alternative solutions.

Compliance: The SR-5-2.5A-AP carries expanded regulatory approvals (CCC, cULus, KC-MARK, PSE, SEMKO, VDE) and RoHS compliance, providing broader market acceptance.

Frequently Asked Questions (FAQ)

Q: Can the SR-5-2.5A-AP directly replace the AP/ETF-2.5 in all applications?

A: No. The substitute is suitable only for applications where the circuit voltage does not exceed 250 V AC. The original part is rated for 277 V AC. Verify the actual operating voltage before substitution.

Q: What is the significance of the different breaking capacities?

A: Breaking capacity indicates the maximum fault current the fuse can safely interrupt. The AP/ETF-2.5 handles 100 A, while the SR-5-2.5A-AP handles 35 A. The substitute must be evaluated against the circuit's maximum fault current to ensure adequate protection.

Q: Are the physical dimensions compatible?

A: Both parts use radial, can-style vertical mounting with through-hole configuration. The AP/ETF-2.5 measures 0.329" Dia x 0.303" H (8.35mm x 7.70mm), while the SR-5-2.5A-AP measures 0.335" Dia x 0.319" H (8.50mm x 8.10mm). The slight dimensional difference must be verified against the specific board layout.

Q: Does the substitute meet the same certifications?

A: Both parts carry SEMKO approval. The substitute additionally holds CCC, cULus, KC-MARK, PSE, and VDE certifications, providing broader regulatory compliance.

Q: What is the impact of the different operating temperature ranges?

A: The AP/ETF-2.5 operates from -55°C to 125°C, while the SR-5-2.5A-AP operates from -40°C to 85°C. Applications requiring operation outside -40°C to 85°C cannot use the substitute.

Q: Is the SR-5-2.5A-AP RoHS compliant?

A: Yes, the SR-5-2.5A-AP is RoHS compliant. The original AP/ETF-2.5 RoHS status is not specified in the provided data.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message