AP/ETF-1 Equivalent & Substitute Parts Reference

Part Overview

The AP/ETF-1 is a 1 A, 277 V AC board mount radial fuse manufactured by Eaton - Electronics Division. This component is classified as obsolete, necessitating identification of equivalent substitute parts for ongoing system maintenance and new designs. The AP/ETF-1 features slow blow response characteristics and is rated for through-hole radial mounting in vertical orientation. Due to its obsolete status, active equivalent parts from alternative manufacturers are required for procurement and design continuity.

Substiute Parts

AP/ETF-1

Eaton - Electronics DivisionIn Stock: 906AP/ETF-1 Datasheet

Current PartRFQ

SR-5-1A-AP

Eaton - Electronics DivisionIn Stock: 8503SR-5-1A-AP Datasheet

SimilarRFQ

0034.6815

SCHURTER Inc.In Stock: 53400034.6815 Datasheet

SimilarRFQ

37211000411

Littelfuse Inc.In Stock: 194937211000411 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AP/ETF-1 is determined by the following critical parameters: current rating (1 A), fuse type (board mount radial), mounting configuration (through-hole vertical), and response time (slow blow). All substitute parts maintain the 1 A current rating and slow blow response characteristic.

The primary distinction among substitutes is voltage rating. The AP/ETF-1 operates at 277 V AC, while available substitutes operate at 250 V AC or 250 V AC / 125 V DC. Substitution is permissible only in applications where the system voltage does not exceed the substitute part's voltage rating. Physical dimensions vary slightly among substitutes but remain compatible with standard through-hole radial mounting footprints. Breaking capacity ratings differ across substitutes and must be evaluated against circuit protection requirements.

Parameter Comparison

Engineering Selection Recommendations

SR-5-1A-AP (Eaton - Electronics Division): This substitute maintains manufacturer continuity with the original AP/ETF-1. It is active in production and carries multiple international certifications including CCC, cULus, KC-MARK, PSE, SEMKO, and VDE. The voltage rating is reduced to 250 V AC, limiting application to systems operating at or below this voltage. Operating temperature range is -40°C ~ 85°C, narrower than the original part. RoHS3 compliance and REACH unaffected status are confirmed.

0034.6815 (SCHURTER Inc.): This substitute provides the widest operating temperature range (-55°C ~ 125°C), matching the original AP/ETF-1 specification. It includes dual voltage rating capability (250 V AC / 125 V DC) and the highest melting I²t value (12), offering enhanced thermal stability. International certifications include CCC, cURus, KC, PSE/JET, and VDE. RoHS3 compliance and REACH unaffected status are confirmed. Physical dimensions are slightly larger than the original part.

37211000411 (Littelfuse Inc. TR5® 372 Series): This substitute is active in production with certifications including CCC, cURus, PSE, SEMKO, and VDE. The voltage rating is 250 V AC. Operating temperature range is -40°C ~ 85°C. DC cold resistance is the lowest among substitutes at 0.079 Ohms. RoHS3 compliance and REACH unaffected status are confirmed. Physical dimensions are comparable to other substitutes.

All substitute parts are suitable for applications where system voltage does not exceed 250 V AC. Selection should account for operating temperature requirements, breaking capacity specifications, and regulatory compliance needs specific to the application.

Frequently Asked Questions (FAQ)

Q: Can the AP/ETF-1 be directly replaced with any of the listed substitutes?

A: Direct replacement is possible only in applications where system voltage does not exceed 250 V AC. The AP/ETF-1 is rated for 277 V AC, while all substitutes are rated for 250 V AC maximum. Substitution in 277 V AC systems is not permissible.

Q: What is the primary difference between the substitute parts?

A: The primary differences are voltage rating, operating temperature range, and breaking capacity. The 0034.6815 offers the widest operating temperature range (-55°C ~ 125°C) and dual voltage capability (250 V AC / 125 V DC). The SR-5-1A-AP and 37211000411 are limited to -40°C ~ 85°C operating temperature.

Q: Are all substitute parts RoHS compliant?

A: Yes, all three substitute parts are RoHS3 compliant and REACH unaffected.

Q: Do the substitute parts have different physical dimensions?

A: Yes, all substitute parts have slightly larger dimensions than the original AP/ETF-1. The original is 0.329" Dia x 0.303" H (8.35mm x 7.70mm), while substitutes range from 0.335" Dia x 0.315" H to 0.335" Dia x 0.335" H. These dimensional differences are minor and typically compatible with standard through-hole radial mounting footprints, but PCB layout verification is necessary.

Q: Which substitute has the highest breaking capacity?

A: The 0034.6815 has the highest breaking capacity at 35 A AC / 50 A DC. The SR-5-1A-AP and 37211000411 both have 35 A breaking capacity. The original AP/ETF-1 has 100 A breaking capacity, which is not matched by any substitute.

Q: What certifications do the substitute parts carry?

A: All substitutes carry multiple international certifications. The 0034.6815 carries the most comprehensive set including CCC, cURus, KC, PSE/JET, and VDE. The SR-5-1A-AP includes CCC, cULus, KC-MARK, PSE, SEMKO, and VDE. The 37211000411 includes CCC, cURus, PSE, SEMKO, and VDE.

Q: Is the 0034.6815 suitable for DC applications?

A: The 0034.6815 is rated for 125 V DC, making it suitable for DC applications within this voltage specification. The other substitutes do not specify DC voltage ratings.

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

A: The melting I²t value indicates the thermal energy required to melt the fuse element. The 0034.6815 has the highest value (12), followed by SR-5-1A-AP and 37211000411 (both 7.5), and the original AP/ETF-1 (5.9). Higher values indicate greater thermal stability and slower response to transient overcurrent conditions.