Ohmite 45F2K5 Equivalent & Substitute Parts

Part Overview

The Ohmite 45F2K5 is a 2.5 kOhms ±1% 5W through-hole resistor with axial wirewound construction, part of the Ohmicone® 40 series. This component is currently active in production with 1153 units in stock. Equivalent and substitute parts are identified to support procurement flexibility, inventory management, and supply chain continuity when the primary part becomes unavailable or when alternative packaging or compliance requirements necessitate component substitution.

Substiute Parts

45F2K5

OhmiteIn Stock: 118945F2K5 Datasheet

Current PartRFQ

45F2K5E

OhmiteIn Stock: 125245F2K5E Datasheet

DirectRFQ

ALSR052K500FE12

Vishay DaleIn Stock: 893ALSR052K500FE12 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 45F2K5 are qualified based on the following critical parameters:

• Resistance value: 2.5 kOhms (exact match required)
• Tolerance: ±1% (exact match required)
• Power rating: 5W (exact match required)
• Composition: Wirewound (exact match required)
• Package: Axial through-hole (exact match required)
• Number of terminations: 2 (exact match required)

The identified substitutes maintain electrical equivalence across all core functional parameters. Variations in temperature coefficient, operating temperature range, physical dimensions, and compliance certifications are noted but do not preclude functional substitution within the specified electrical envelope.

Parameter Comparison

Engineering Selection Recommendations

45F2K5E (Ohmite): This direct manufacturer equivalent maintains identical electrical specifications and physical dimensions to the primary part 45F2K5. The primary distinction is packaging format (Bulk) and RoHS3 compliance status. Selection of 45F2K5E is appropriate for applications requiring RoHS3 compliance or when bulk packaging aligns with procurement requirements.

ALSR052K500FE12 (Vishay Dale): This substitute maintains electrical equivalence across resistance, tolerance, and power rating. Physical dimensions are slightly smaller (0.312" Dia x 0.875" L versus 0.343" Dia x 0.937" L). The ALSR series includes moisture-resistant construction and specifies an operating temperature range of -65°C ~ 250°C. Temperature coefficient is ±30ppm/°C, representing a 50% increase relative to the primary part. RoHS3 compliance is confirmed. Selection of ALSR052K500FE12 is appropriate for applications requiring moisture resistance, extended temperature operation, or RoHS3 compliance, provided that the slightly reduced physical dimensions and increased temperature coefficient are compatible with circuit design requirements.

Frequently Asked Questions (FAQ)

Q: Can 45F2K5E be used as a direct replacement for 45F2K5?

A: Yes. Both parts are manufactured by Ohmite, share identical resistance (2.5 kOhms), tolerance (±1%), power rating (5W), composition (wirewound), package type (axial), and physical dimensions. The primary difference is RoHS3 compliance status of 45F2K5E. Functional substitution is direct.

Q: What are the physical dimension differences between 45F2K5 and ALSR052K500FE12?

A: The 45F2K5 measures 0.343" diameter × 0.937" length (8.70mm × 23.80mm). The ALSR052K500FE12 measures 0.312" diameter × 0.875" length (7.92mm × 22.23mm). The Vishay Dale part is approximately 6.5% shorter and 9% smaller in diameter. Verify PCB layout and component spacing compatibility before substitution.

Q: Does the ±30ppm/°C temperature coefficient of ALSR052K500FE12 affect circuit performance compared to ±20ppm/°C?

A: Temperature coefficient determines resistance drift over temperature. The ALSR052K500FE12 exhibits 50% greater temperature-dependent resistance variation. For precision analog circuits or temperature-sensitive applications, evaluate whether this increased drift remains within circuit tolerance budgets. For general-purpose applications, this difference is typically negligible.

Q: Are all three parts RoHS compliant?

A: No. The primary part 45F2K5 is RoHS non-compliant. Both 45F2K5E and ALSR052K500FE12 are ROHS3 compliant. Applications subject to RoHS requirements must use either 45F2K5E or ALSR052K500FE12.

Q: Can ALSR052K500FE12 be used in applications requiring moisture resistance?

A: Yes. The ALSR052K500FE12 includes moisture-resistant construction as a specified feature. The 45F2K5 and 45F2K5E do not list moisture resistance. For applications exposed to humidity or moisture environments, ALSR052K500FE12 is the appropriate selection.

Q: What is the operating temperature range for 45F2K5?

A: Operating temperature is not specified in the provided data for 45F2K5. The ALSR052K500FE12 specifies -65°C ~ 250°C. For applications requiring defined temperature operation limits, ALSR052K500FE12 provides explicit specification.