KTK-1/4 Equivalent & Substitute Parts

Part Overview

The KTK-1/4 is a 250mA fast-blow cartridge fuse rated for 600 VAC operation, manufactured by Eaton - Bussmann Electrical Division. This component is designed for electrical and industrial applications requiring overcurrent protection in AC circuits. The part maintains active product status with 958 units in current inventory. Substitute parts are identified to provide alternative sourcing options when the primary manufacturer part is unavailable or when system design requires components from alternative manufacturers meeting identical electrical and mechanical specifications.

Substiute Parts

KTK-1/4

Eaton - Bussmann Electrical DivisionIn Stock: 1054KTK-1/4 Datasheet

Current PartRFQ

KLKR.250T

Littelfuse Inc.In Stock: 1008KLKR.250T Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the KTK-1/4 is determined by strict equivalence across the following critical parameters:

• Current Rating: 250mA (exact match required)
• Voltage Rating - AC: 600 VAC (exact match required)
• Fuse Type: Cartridge (exact match required)
• Response Time: Fast Blow (exact match required)
• Package / Case: 5AG, 10mm x 38mm Midget (exact match required)
• Physical Dimensions: 0.406" Dia x 1.500" L (exact match required)
• Mounting Configuration: Requires Holder (exact match required)

The KLKR.250T from Littelfuse Inc. meets all mandatory substitution criteria for AC circuit applications. This part provides equivalent electrical performance in 600 VAC systems while maintaining identical mechanical compatibility with standard 5AG cartridge fuse holders.

Parameter Comparison

Engineering Selection Recommendations

Both the KTK-1/4 and KLKR.250T maintain active product status and carry CSA and UL certifications, confirming suitability for North American electrical applications. The KLKR.250T provides additional DC voltage rating capability (300 VDC) and higher breaking capacity (200kA AC versus 100kA), which may be advantageous in applications requiring dual-voltage operation or enhanced fault protection margins. Both components satisfy RoHS compliance requirements for environmental standards. Selection between these parts should be based on circuit voltage requirements, available inventory, and system design specifications for breaking capacity.

Frequently Asked Questions (FAQ)

Q: Can the KLKR.250T replace the KTK-1/4 in existing 600 VAC circuits?

A: Yes. Both parts share identical current rating (250mA), AC voltage rating (600 VAC), fuse type (cartridge), response time (fast blow), and physical dimensions (5AG, 10mm x 38mm). They are mechanically and electrically interchangeable in 600 VAC applications.

Q: What is the significance of the DC voltage rating on the KLKR.250T?

A: The KLKR.250T includes a 300 VDC rating, which the KTK-1/4 does not specify. This additional rating allows the Littelfuse part to function in mixed-voltage or DC circuit applications. For AC-only circuits, this parameter does not affect compatibility.

Q: Are both parts compatible with standard 5AG fuse holders?

A: Yes. Both the KTK-1/4 and KLKR.250T use the 5AG package specification with identical 10mm x 38mm dimensions (0.406" Dia x 1.500" L). They install directly into any standard 5AG cartridge fuse holder without modification.

Q: What certifications apply to both parts?

A: Both parts carry CSA and UL certifications. The KLKR.250T additionally carries CE certification. All certifications confirm compliance with electrical safety standards for industrial and electrical applications.

Q: How do breaking capacities differ between these parts?

A: The KTK-1/4 has a breaking capacity of 100kA at rated voltage. The KLKR.250T provides 200kA AC and 20kA DC. Higher breaking capacity indicates greater ability to safely interrupt fault currents. Selection depends on system fault current levels and design requirements.