Equivalent & Substitute Parts for 45F12R

Part Overview

The 45F12R is a 12 Ohm, 1% tolerance, 5W axial wirewound resistor manufactured by Ohmite as part of the Ohmicone® 40 series. This through-hole component is designed for applications requiring precision resistance with moderate power dissipation in a compact axial package. The part maintains active product status with 786 units currently in stock. Substitute parts are necessary to address supply chain flexibility, compliance requirements, or packaging preferences while maintaining electrical and mechanical compatibility.

Substiute Parts

45F12R

OhmiteIn Stock: 82045F12R Datasheet

Current PartRFQ

45F12RE

OhmiteIn Stock: 83645F12RE Datasheet

DirectRFQ

ALSR0512R00FE12

Vishay DaleIn Stock: 991ALSR0512R00FE12 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 45F12R is determined by the following critical parameters:

• Resistance value: 12 Ohms (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 substitute parts meet all mandatory electrical parameters. Variations in temperature coefficient, physical dimensions within tolerance, and RoHS compliance status do not affect functional substitutability for standard circuit applications.

Parameter Comparison

Engineering Selection Recommendations

All three parts are electrically equivalent for standard circuit applications requiring a 12 Ohm, 1% tolerance, 5W axial wirewound resistor.

45F12RE (Ohmite): Direct manufacturer equivalent with identical electrical specifications and physical dimensions. Offers ROHS3 compliance, addressing regulatory requirements where RoHS compliance is mandated. Recommended for applications with RoHS compliance requirements while maintaining Ohmite series continuity.

ALSR0512R00FE12 (Vishay Dale): Functionally equivalent with slightly higher temperature coefficient (±30ppm/°C versus ±20ppm/°C) and compact physical dimensions (0.312" Dia x 0.875" L). Includes moisture-resistant construction and extended operating temperature range (-65°C ~ 250°C). ROHS3 compliant. Recommended for space-constrained layouts or applications requiring enhanced environmental protection.

Selection between 45F12RE and ALSR0512R00FE12 depends on manufacturer preference, compliance requirements, and physical space constraints rather than electrical performance.

Frequently Asked Questions (FAQ)

Q: Can ALSR0512R00FE12 be used as a direct replacement for 45F12R in all applications?

A: Yes, for standard circuit applications. The ALSR0512R00FE12 meets all critical electrical parameters (12 Ohms, ±1%, 5W, wirewound, axial). The slightly higher temperature coefficient (±30ppm/°C) and compact dimensions are acceptable for most applications. Verify physical fit in space-constrained PCB layouts due to smaller diameter (0.312" versus 0.343").

Q: What is the difference between 45F12R and 45F12RE?

A: Both are Ohmite Ohmicone® 40 series resistors with identical electrical specifications and physical dimensions. The primary difference is RoHS compliance status: 45F12R is RoHS non-compliant, while 45F12RE is ROHS3 compliant. Select 45F12RE for applications or markets requiring RoHS certification.

Q: Are there any compatibility concerns with PCB footprints?

A: The 45F12R and 45F12RE share identical dimensions (0.343" Dia x 0.937" L) and are footprint-compatible. The ALSR0512R00FE12 has a smaller diameter (0.312") and slightly shorter length (0.875" L), which may affect fit in legacy PCB designs with tightly spaced component pads. Verify clearance before substitution.

Q: Which substitute part offers the best environmental performance?

A: The ALSR0512R00FE12 includes moisture-resistant construction and operates across an extended temperature range (-65°C ~ 250°C) compared to the Ohmite parts. This makes it suitable for harsh environmental applications, though all three parts are suitable for standard industrial conditions.

Q: Can these parts be used interchangeably in high-precision circuits?

A: The 45F12R and 45F12RE are preferred for high-precision applications due to their lower temperature coefficient (±20ppm/°C). The ALSR0512R00FE12, with ±30ppm/°C, introduces slightly greater temperature-dependent resistance variation. For circuits sensitive to temperature drift, use 45F12R or 45F12RE.