Ohmite 43F270 Equivalent & Substitute Parts

Part Overview

The Ohmite 43F270 is a 270 Ohms ±1% 3W through-hole resistor with axial wirewound construction, part of the Ohmicone® 40 series. This component is designed for applications requiring precision resistive elements with moderate power dissipation in compact form factors. The part maintains active product status and is available in high inventory volume. Substitute parts are identified to provide alternative sourcing options when the primary manufacturer part becomes unavailable or when procurement requirements necessitate component alternatives that meet equivalent electrical and mechanical specifications.

Substiute Parts

43F270

OhmiteIn Stock: 103643F270 Datasheet

Current PartRFQ

ALSR03270R0FE12

Vishay DaleIn Stock: 2526ALSR03270R0FE12 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the Ohmite 43F270 are qualified based on the following critical parameters that determine functional equivalence:

• Resistance Value: 270 Ohms (exact match required)
• Tolerance: ±1% (precision specification)
• Power Rating: 3W (thermal design requirement)
• Composition: Wirewound (construction type)
• Package: Axial (form factor and termination style)
• Terminations: 2 (electrical connection points)

The Vishay Dale ALSR03270R0FE12 qualifies as a direct substitute because it matches all critical electrical parameters and maintains the same axial package configuration. Variations in physical dimensions, temperature coefficient, and compliance certifications do not preclude substitution when the electrical performance envelope and mechanical interface remain compatible.

Parameter Comparison

Engineering Selection Recommendations

Both the Ohmite 43F270 and Vishay Dale ALSR03270R0FE12 are active products with established supply chains. The Ohmite part is non-RoHS compliant, while the Vishay Dale substitute achieves ROHS3 compliance. Selection between these parts should be based on regulatory requirements specific to the end application. The Vishay Dale ALSR03270R0FE12 provides an alternative for applications requiring RoHS compliance or extended operating temperature range documentation. Physical dimension differences (smaller diameter and length in the Vishay part) may affect board layout considerations and should be evaluated against mechanical constraints in the target application.

Frequently Asked Questions (FAQ)

Q: Can the Vishay Dale ALSR03270R0FE12 be used as a direct replacement for the Ohmite 43F270?

A: Yes, the Vishay Dale part qualifies as a direct electrical substitute. Both components share identical resistance value (270 Ohms), tolerance (±1%), power rating (3W), composition (wirewound), and axial package configuration. Physical dimensions differ slightly, requiring verification of board layout compatibility.

Q: What is the significance of the temperature coefficient difference between these parts?

A: The Ohmite part specifies ±20ppm/°C while the Vishay Dale substitute specifies ±30ppm/°C. This difference affects resistance stability across temperature extremes. For applications operating within moderate temperature ranges, this variation is typically negligible. Applications requiring tighter temperature stability should retain the Ohmite specification.

Q: Does the RoHS compliance difference affect substitution eligibility?

A: RoHS compliance is a regulatory and supply chain consideration rather than an electrical performance factor. The Vishay Dale ALSR03270R0FE12 achieves ROHS3 compliance, making it suitable for applications subject to RoHS regulations. The Ohmite part's non-compliance status does not affect electrical function but may restrict use in regulated markets.

Q: Are the physical dimension differences critical for substitution?

A: Physical dimensions should be evaluated against specific board layout and mechanical mounting requirements. The Vishay Dale part is smaller (0.180" Dia x 0.500" L versus 0.220" Dia x 0.594" L), which may provide advantages in space-constrained designs but requires confirmation that the smaller form factor does not conflict with existing mechanical constraints or thermal management considerations.

Q: What inventory considerations apply to these parts?

A: The Ohmite 43F270 maintains 948 pieces in stock, while the Vishay Dale ALSR03270R0FE12 has 2419 pieces available. The Vishay part offers higher inventory availability for high-volume procurement scenarios.