45F1K5 Equivalent & Substitute Parts Reference

Part Overview

The 45F1K5 is a 1.5 kOhms ±1% 5W axial wirewound through-hole resistor manufactured by Ohmite, part of the Ohmicone® 40 series. This component is currently active in production with 968 units in stock. Wirewound resistors of this specification are used in applications requiring precise resistance values with high power dissipation capabilities. Substitute parts may be required due to supply chain constraints, regional availability, or specific compliance requirements for end applications.

Substiute Parts

45F1K5

OhmiteIn Stock: 105245F1K5 Datasheet

Current PartRFQ

ALSR051K500FE12

Vishay DaleIn Stock: 1020ALSR051K500FE12 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 45F1K5 is determined by the following critical parameters:

• Resistance Value: Must be 1.5 kOhms
• Tolerance: Must be ±1% or tighter
• Power Rating: Must be 5W or greater
• Composition: Must be wirewound
• Package: Must be axial through-hole
• Termination Count: Must be 2-pin

The ALSR051K500FE12 (Vishay Dale) meets all substitution criteria. Both components share identical electrical specifications for resistance, tolerance, and power rating. Both utilize axial wirewound construction with two terminations. Physical dimensions are comparable within acceptable PCB layout tolerances for through-hole axial components.

Parameter Comparison

Engineering Selection Recommendations

45F1K5 (Ohmite): Select this part for applications where RoHS non-compliant components are acceptable and the tighter temperature coefficient (±20ppm/°C) is required for precision circuit performance.

ALSR051K500FE12 (Vishay Dale): Select this substitute when RoHS3 compliance is mandated for the end application. The ROHS3 compliant status and moisture-resistant construction provide enhanced environmental protection. The slightly higher temperature coefficient (±30ppm/°C) remains within acceptable tolerance for most general-purpose 5W resistor applications. The defined operating temperature range (-65°C ~ 250°C) provides explicit thermal performance boundaries.

Both parts are active products with current inventory availability.

Frequently Asked Questions (FAQ)

Q: Can ALSR051K500FE12 be used as a direct replacement for 45F1K5?

A: Yes. Both components share identical resistance (1.5 kOhms), tolerance (±1%), power rating (5W), composition (wirewound), and package type (axial). Physical dimensions are comparable for through-hole PCB mounting. The ALSR051K500FE12 includes moisture-resistant construction and RoHS3 compliance as additional features.

Q: What is the difference in temperature coefficient between these parts?

A: The 45F1K5 has a temperature coefficient of ±20ppm/°C, while the ALSR051K500FE12 has ±30ppm/°C. For most applications, this 10ppm/°C difference is negligible. Applications requiring the tighter coefficient should specify the 45F1K5.

Q: Are there physical dimension differences that affect PCB layout?

A: The ALSR051K500FE12 is slightly smaller (0.312" Dia x 0.875" L) compared to the 45F1K5 (0.343" Dia x 0.937" L). Both fit standard axial component footprints. The smaller substitute may provide minor PCB layout advantages in space-constrained designs.

Q: Does RoHS compliance matter for my application?

A: RoHS compliance is required for products sold in the European Union and many other regulated markets. The ALSR051K500FE12 is ROHS3 compliant, while the 45F1K5 is non-compliant. Verify your end-product regulatory requirements before component selection.

Q: What is the moisture-resistant feature on the ALSR051K500FE12?

A: Moisture-resistant construction provides enhanced protection in humid or corrosive environments. This feature does not affect electrical performance but extends component reliability in challenging operating conditions.