ECSR125 Equivalent & Substitute Parts Reference

Part Overview

The ECSR125 is a 125A 600VAC cylindrical fuse cartridge manufactured by Eaton - Bussmann Electrical Division. This component is designed for electrical and industrial applications requiring slow-blow response characteristics and RK5 class protection. The part is currently active in production with 866 units in stock. Alternative equivalent parts may be required due to application-specific voltage requirements, supply chain considerations, or system design modifications that necessitate dual AC/DC voltage capability.

Substiute Parts

ECSR125

Eaton - Bussmann Electrical DivisionIn Stock: 932ECSR125 Datasheet

Current PartRFQ

FRS-R-125

Eaton - Bussmann Electrical DivisionIn Stock: 967FRS-R-125 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

The FRS-R-125 qualifies as an equivalent substitute for the ECSR125 based on the following critical parameters:

Matching Parameters:

• Current Rating: 125A (identical)
• Voltage Rating - AC: 600 VAC (identical)
• Fuse Type: Cartridge (identical)
• Response Time: Slow Blow (identical)
• Class: RK5 (identical)
• Size / Dimension: 1.610" Dia x 9.630" L (identical)
• Mounting Type: Requires Holder (identical)
• Breaking Capacity @ Rated Voltage: 200kA AC (identical)
• RoHS Status: RoHS Compliant (identical)
• Approval Agencies: CE, CSA, UL (identical)

Extended Capability: The FRS-R-125 provides additional DC voltage rating (300 VDC) not present in the ECSR125, making it suitable for applications requiring dual AC/DC operation while maintaining full AC compatibility.

Parameter Comparison

Engineering Selection Recommendations

Both the ECSR125 and FRS-R-125 are active products manufactured by Eaton - Bussmann Electrical Division with identical certifications (CE, CSA, UL) and RoHS compliance. Selection between these parts depends on application voltage requirements:

Select ECSR125 when:

• Application operates exclusively on AC power at 600 VAC
• DC voltage capability is not required
• Standard RK5 cartridge fuse protection is specified

Select FRS-R-125 when:

• Application requires dual AC/DC operation capability
• System design includes 300 VDC circuits
• Extended voltage range compatibility is beneficial for multi-voltage installations
• Standardization on a single part number across AC and DC applications is preferred

Both parts maintain identical mechanical compatibility, electrical performance at 125A 600 VAC, and regulatory compliance. The choice is determined by whether DC voltage rating is operationally necessary.

Frequently Asked Questions (FAQ)

Q: Can FRS-R-125 be used as a direct replacement for ECSR125 in AC-only applications?

A: Yes. The FRS-R-125 maintains identical AC voltage rating (600 VAC), current rating (125A), response time (Slow Blow), and RK5 class characteristics. The additional 300 VDC rating does not affect AC performance and does not create incompatibility in AC-only circuits.

Q: Are the physical dimensions identical between ECSR125 and FRS-R-125?

A: Yes. Both parts measure 1.610" Dia x 9.630" L (40.89mm x 244.60mm) and require the same holder mounting configuration.

Q: Do both parts carry the same regulatory approvals?

A: Yes. Both ECSR125 and FRS-R-125 hold CE, CSA, and UL certifications and are RoHS compliant.

Q: What is the difference in breaking capacity between these parts?

A: At 600 VAC (rated voltage), both parts provide 200kA breaking capacity. The FRS-R-125 additionally specifies 20kA breaking capacity at 300 VDC, which is not applicable to ECSR125 as it is not rated for DC operation.

Q: Which part should be selected for new equipment designs?

A: Selection depends on system voltage requirements. For AC-only systems, either part is acceptable. For systems requiring future DC capability or multi-voltage flexibility, FRS-R-125 provides extended application range without performance compromise in AC circuits.