Ohmite 45F125 Equivalent & Substitute Parts

Part Overview

The Ohmite 45F125 is a 125 Ohm, ±1% tolerance, 5W through-hole axial wirewound resistor from the Ohmicone® 40 series. This component is currently in active production status with 808 units available in new original inventory. The part is classified as RoHS non-compliant and is suitable for applications requiring precision resistive elements in axial configuration. Substitute parts are identified when equivalent electrical specifications and mechanical compatibility are maintained across the allowed parameter set.

Substiute Parts

45F125

OhmiteIn Stock: 86345F125 Datasheet

Current PartRFQ

45F125E

OhmiteIn Stock: 134645F125E Datasheet

DirectRFQ

ALSR05125R0FE12

Vishay DaleIn Stock: 2282ALSR05125R0FE12 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the Ohmite 45F125 are qualified based on the following criteria:

Electrical Parameters (Must Match):

• Resistance value: 125 Ohms
• Tolerance: ±1%
• Power rating: 5W
• Composition: Wirewound

Mechanical Parameters (Must Match):

• Package configuration: Axial through-hole
• Number of terminations: 2

Allowed Variations:

• Temperature coefficient (within engineering tolerance for the application)
• Physical dimensions (within standard axial package ranges)
• RoHS compliance status (compliance is not a substitution barrier for this product category)
• Moisture resistance features (enhancement features do not prevent substitution)

The identified substitutes maintain electrical equivalence and mechanical compatibility with the main part across all critical parameters.

Parameter Comparison

Engineering Selection Recommendations

Ohmite 45F125E: This direct Ohmite substitute maintains identical electrical specifications (125 Ohms, ±1%, 5W) and axial package configuration. Both parts share RoHS non-compliant status and active product status. Selection of this part is appropriate when maintaining the original manufacturer specification is required or when inventory of the primary part is constrained.

Vishay Dale ALSR05125R0FE12: This substitute provides equivalent electrical performance (125 Ohms, ±1%, 5W wirewound) in an axial package with identical termination count. The Vishay Dale part offers ROHS3 compliance, which may be advantageous in applications subject to RoHS regulatory requirements. The slightly tighter temperature coefficient (±30ppm/°C versus ±20ppm/°C) and extended operating temperature range (-65°C ~ 250°C) provide enhanced performance margins. Physical dimensions are within standard axial package tolerances. This part is suitable for applications where RoHS compliance is a system requirement.

Selection between substitutes should be based on regulatory compliance requirements, inventory availability, and specific application temperature operating conditions.

Frequently Asked Questions (FAQ)

Q: Can the Ohmite 45F125E be used as a direct replacement for the Ohmite 45F125?

A: Yes. Both parts are manufactured by Ohmite and share identical electrical specifications (125 Ohms, ±1%, 5W) and axial package configuration. The parts are electrically and mechanically interchangeable.

Q: Is the Vishay Dale ALSR05125R0FE12 compatible with the Ohmite 45F125?

A: Yes. The Vishay Dale part meets all electrical requirements (125 Ohms, ±1%, 5W wirewound) and mechanical compatibility (axial through-hole, 2 terminations). Physical dimensions are within standard axial package ranges. The part is suitable for direct substitution.

Q: What is the significance of RoHS compliance status in selecting a substitute?

A: RoHS compliance status indicates regulatory conformance for specific applications and markets. The Vishay Dale ALSR05125R0FE12 is ROHS3 compliant, while both Ohmite parts are RoHS non-compliant. Selection should align with the regulatory requirements of the end application and target market.

Q: Are there dimensional compatibility concerns when substituting the Vishay Dale part?

A: The Vishay Dale ALSR05125R0FE12 has slightly smaller dimensions (0.312" Dia x 0.875" L) compared to the Ohmite 45F125 (0.343" Dia x 0.937" L). Both are within standard axial package specifications. Verify PCB layout and mechanical clearances for your specific application before substitution.

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

A: The Ohmite 45F125 has a temperature coefficient of ±20ppm/°C, while the Vishay Dale ALSR05125R0FE12 has ±30ppm/°C. Both values are within acceptable ranges for precision resistor applications. The Ohmite part offers a tighter coefficient; the Vishay Dale part provides an extended operating temperature range (-65°C ~ 250°C).

Q: Which substitute should be selected for maximum inventory availability?

A: The Vishay Dale ALSR05125R0FE12 has the highest inventory availability at 2228 units, followed by the Ohmite 45F125E at 1273 units, and the primary Ohmite 45F125 at 808 units.