Ohmite 40F125 125 Ohm 10W Axial Wirewound Resistor - Equivalent & Substitute Parts

Part Overview

The Ohmite 40F125 is a 125 Ohm, ±1% tolerance, 10W through-hole axial wirewound resistor from the Ohmicone® 40 series. This component is designed for applications requiring precise resistance values with high power dissipation capability in a compact axial package. The part maintains active product status with 1098 units currently in stock. Substitute parts are identified when packaging configurations differ or when compliance requirements necessitate alternative sourcing while maintaining identical electrical and mechanical specifications.

Substiute Parts

40F125

OhmiteIn Stock: 119040F125 Datasheet

Current PartRFQ

40F125E

OhmiteIn Stock: 81640F125E Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the Ohmite 40F125 is determined by strict equivalence across the following critical parameters:

• Resistance value: 125 Ohms
• Tolerance: ±1%
• Power rating: 10W
• Composition: Wirewound
• Package configuration: Axial
• Temperature coefficient: ±20ppm/°C
• Physical dimensions: 0.406" Dia x 1.902" L

The identified substitute part, 40F125E, maintains identical electrical and mechanical specifications. The primary distinction is packaging configuration (Bulk versus standard) and RoHS compliance status. Both parts are manufactured by Ohmite and belong to the same Ohmicone® 40 series.

Parameter Comparison

Engineering Selection Recommendations

Selection between the 40F125 and 40F125E is determined by regulatory and procurement requirements:

The 40F125E is the appropriate choice for applications subject to ROHS3 compliance mandates. Both parts deliver identical electrical performance and mechanical fit within the same circuit design.

The 40F125 remains suitable for applications without RoHS compliance requirements and offers higher current inventory availability.

Bulk packaging of the 40F125E accommodates high-volume production environments, while standard packaging of the 40F125 supports lower-volume or prototype applications.

Frequently Asked Questions (FAQ)

Q: Are the 40F125 and 40F125E electrically interchangeable?

A: Yes. Both parts deliver 125 Ohms ±1% resistance at 10W power rating with identical temperature coefficient and wirewound composition. They are direct electrical equivalents.

Q: What is the difference between these two part numbers?

A: The primary differences are packaging configuration (Bulk versus standard) and RoHS compliance status. The 40F125E meets ROHS3 requirements, while the 40F125 does not.

Q: Can I use the 40F125E as a direct replacement for the 40F125 in my circuit?

A: Yes. The 40F125E is a direct mechanical and electrical substitute. Physical dimensions, termination configuration, and all electrical parameters are identical.

Q: Does packaging type affect circuit performance?

A: No. Bulk and standard packaging refer only to how components are supplied and do not affect electrical or mechanical performance in the circuit.

Q: Which part should I select for new designs?

A: Selection depends on regulatory requirements. For ROHS3-compliant applications, specify the 40F125E. For applications without RoHS mandates, either part is acceptable based on availability and packaging needs.

Q: Are both parts currently available?

A: Yes. The 40F125 has 1098 units in stock, and the 40F125E has 774 units in stock.