KTK-1/8 Equivalent & Substitute Parts

Part Overview

The KTK-1/8 is a 125mA fast-blow cartridge fuse rated for 600 VAC operation, manufactured by Eaton - Bussmann Electrical Division. This fuse is designed for use in electrical and industrial applications requiring a holder-mounted cartridge configuration. The part maintains active product status with 1107 units in current inventory. Substitute parts are identified when equivalent electrical ratings, mechanical dimensions, and approval certifications align with the original specification, enabling direct replacement in compatible fuse holders.

Substiute Parts

KTK-1/8

Eaton - Bussmann Electrical DivisionIn Stock: 1119KTK-1/8 Datasheet

Current PartRFQ

0KLK.125T

Littelfuse Inc.In Stock: 10840KLK.125T Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

The 0KLK.125T from Littelfuse Inc. qualifies as a direct substitute based on the following alignment of critical parameters:

• Current Rating: 125mA (identical)
• Voltage Rating - AC: 600 VAC (identical)
• Fuse Type: Cartridge (identical)
• Response Time: Fast Blow (identical)
• Package / Case: 5AG, 10mm x 38mm (Midget) (identical)
• Size / Dimension: 0.406" Dia x 1.500" L (10.31mm x 38.10mm) (equivalent within tolerance)
• Breaking Capacity @ Rated Voltage: 100kA AC (identical)
• Approval Agency: Includes CSA and UL certifications (meets or exceeds original)

The substitute part maintains mechanical and electrical compatibility with the original specification, enabling installation in the same holder configuration without modification.

Parameter Comparison

Engineering Selection Recommendations

Both the KTK-1/8 and 0KLK.125T maintain active product status and carry CSA and UL certifications required for electrical and industrial applications. The 0KLK.125T provides additional DC voltage rating capability (500 VDC) and expanded approval certifications (CE, QPL) beyond the original specification. For AC-only applications at 600 VAC with 125mA current requirements, either part satisfies the electrical and mechanical requirements. The substitute part's enhanced compliance profile (ROHS3 vs. RoHS Compliant) and additional certifications present no compatibility concerns for direct replacement in existing fuse holder assemblies.

Frequently Asked Questions (FAQ)

Q: Can the 0KLK.125T replace the KTK-1/8 in existing installations?

A: Yes. Both parts share identical current rating (125mA), AC voltage rating (600 VAC), fuse type (cartridge), response time (fast blow), and mechanical dimensions (5AG, 10mm x 38mm). The substitute part fits the same holder configuration without modification.

Q: What is the significance of the DC voltage rating on the substitute part?

A: The 0KLK.125T includes a 500 VDC rating not specified on the KTK-1/8. This additional capability does not affect AC-only applications and provides expanded flexibility for mixed-voltage circuit designs.

Q: Are the approval certifications equivalent?

A: The substitute part carries CSA and UL certifications matching the original, plus additional CE and QPL approvals. All required certifications for the original application are maintained or exceeded.

Q: Do the dimensional tolerances affect interchangeability?

A: The dimensional difference (10.30mm vs. 10.31mm diameter) is within standard manufacturing tolerance for 5AG cartridge fuses and does not affect holder compatibility.

Q: What is the difference between RoHS Compliant and ROHS3 Compliant?

A: ROHS3 represents the current revision of the RoHS directive with updated substance restrictions. Both designations indicate compliance with hazardous substance limitations; ROHS3 reflects the more recent regulatory standard.