Ohmite 43F500 500 Ohm 3W Axial Wirewound Resistor Equivalent & Substitute Parts

Part Overview

The Ohmite 43F500 is a 500 Ohm ±1% 3W through-hole axial wirewound resistor from the Ohmicone® 40 series. This component is actively manufactured and widely used in applications requiring precision resistive elements with moderate power dissipation. Equivalent and substitute parts are identified to support procurement flexibility, inventory management, and design continuity when the primary part becomes unavailable or when alternative compliance certifications are required.

Substiute Parts

43F500

OhmiteIn Stock: 99243F500 Datasheet

Current PartRFQ

43F500E

OhmiteIn Stock: 124243F500E Datasheet

Parametric EquivalentRFQ

ALSR03500R0FE12

Vishay DaleIn Stock: 1105ALSR03500R0FE12 Datasheet

DirectRFQ

43F500E

OhmiteIn Stock: 124243F500E Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the Ohmite 43F500 are classified based on electrical and mechanical parameter alignment:

Parametric Equivalents: Parts matching all critical electrical specifications (resistance value, tolerance, power rating, composition, and temperature coefficient range) with identical package configuration.

Direct Manufacturer Alternatives: Parts from different manufacturers meeting the same functional requirements with allowable variations in physical dimensions and temperature coefficient within acceptable engineering tolerances.

The following parameters determine substitution eligibility:

• Resistance: 500 Ohms (exact match required)
• Tolerance: ±1% (exact match required)
• Power Rating: 3W (exact match required)
• Composition: Wirewound (exact match required)
• Package: Axial (exact match required)
• Temperature Coefficient: ±20ppm/°C to ±30ppm/°C (acceptable range)

Parameter Comparison

Engineering Selection Recommendations

43F500E (Ohmite): This parametric equivalent is electrically identical to the 43F500 with matching dimensions and temperature coefficient. The primary distinction is RoHS compliance status. Selection of 43F500E is appropriate for applications requiring RoHS-compliant components or when inventory of the original 43F500 is constrained.

ALSR03500R0FE12 (Vishay Dale): This direct manufacturer alternative meets all core electrical specifications with a higher operating temperature range (-65°C ~ 250°C) and moisture-resistant construction. Physical dimensions are slightly smaller (0.180" Dia x 0.500" L versus 0.220" Dia x 0.594" L), which may affect board layout compatibility. The temperature coefficient is ±30ppm/°C, representing a 50% increase in drift compared to the Ohmite variants. This part is suitable for applications requiring extended temperature operation or enhanced moisture resistance, provided the slightly larger temperature coefficient is acceptable for the circuit design.

Frequently Asked Questions (FAQ)

Q: Can ALSR03500R0FE12 be used as a direct replacement for 43F500 in all applications?

A: ALSR03500R0FE12 is electrically compatible as a substitute, meeting the 500 Ohm ±1% 3W specification. However, two factors require evaluation: (1) Physical dimensions are smaller, which may affect board layout and lead spacing; (2) Temperature coefficient is ±30ppm/°C versus ±20ppm/°C for the Ohmite parts, resulting in greater resistance drift over temperature. Verify these parameters against circuit requirements before substitution.

Q: What is the difference between 43F500 and 43F500E?

A: Both parts are electrically and mechanically identical 500 Ohm ±1% 3W axial wirewound resistors from Ohmite's 40 series. The primary difference is RoHS compliance: 43F500 is RoHS non-compliant, while 43F500E is RoHS Compliant. Packaging differs (tape/reel versus bulk), and 43F500E has defined moisture sensitivity level (MSL 1 - Unlimited). Selection depends on compliance requirements and procurement specifications.

Q: Are all three parts interchangeable in terms of physical footprint?

A: No. The Ohmite parts (43F500 and 43F500E) share identical dimensions (0.220" Dia x 0.594" L). The Vishay Dale ALSR03500R0FE12 is physically smaller (0.180" Dia x 0.500" L). While the smaller part may fit in a layout designed for the larger Ohmite resistors, the reverse is not true. Verify PCB layout compatibility before substitution.

Q: Which substitute part should be selected for high-temperature applications?

A: ALSR03500R0FE12 is specified for -65°C ~ 250°C operation, providing the widest temperature range. The Ohmite 43F500 and 43F500E do not specify operating temperature limits. If extended temperature operation is required, ALSR03500R0FE12 is the appropriate selection, with the caveat that its ±30ppm/°C temperature coefficient should be verified against circuit tolerance requirements.

Q: Does moisture resistance matter for this resistor type?

A: ALSR03500R0FE12 includes moisture-resistant construction, while the Ohmite variants do not specify this feature. For applications in humid environments or with moisture exposure risk, the Vishay Dale part provides additional protection. For standard indoor applications, moisture resistance is not a determining factor.