Equivalent & Substitute Parts for Ohmite 825F20R

Part Overview

The Ohmite 825F20R is a 20 Ohms ±1% 25W wirewound chassis mount resistor from the Metal-Mite®89 series. This component is classified as obsolete, making identification of suitable substitute parts essential for ongoing system maintenance and new design implementations. The part features aluminum housing with flanged mounting and solder lug termination, designed for applications requiring precision resistance in high-power environments.

Substiute Parts

825F20R

OhmiteIn Stock: 752825F20R Datasheet

Current PartRFQ

825F20RE

OhmiteIn Stock: 1073825F20RE Datasheet

DirectRFQ

RH02520R00FC02

Vishay DaleIn Stock: 691RH02520R00FC02 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 825F20R is determined by strict equivalence across the following critical parameters:

• Electrical Specifications: Resistance value (20 Ohms), tolerance (±1%), and power rating (25W) must match exactly
• Composition & Construction: Wirewound composition with aluminum housing and flanged mounting configuration
• Thermal Characteristics: Temperature coefficient (±20ppm/°C) and operating temperature range compatibility
• Physical Form Factor: Axial box package with solder lug termination
• Dimensional Compatibility: Length, width, and height within acceptable mechanical tolerances for board-level integration

Two substitute parts meet these criteria: the Ohmite 825F20RE and the Vishay Dale RH02520R00FC02. Both maintain identical electrical and mechanical specifications as the primary part.

Parameter Comparison

Engineering Selection Recommendations

Ohmite 825F20RE: This substitute is the preferred choice for new designs and ongoing production. It maintains identical electrical and mechanical specifications to the 825F20R while offering active product status and ROHS3 compliance. The tray packaging format supports standard manufacturing workflows.

Vishay Dale RH02520R00FC02: This substitute provides functional equivalence with active product status. The operating temperature range extends to 250°C (versus 275°C for the primary part), which is acceptable for most applications within standard industrial operating windows. Dimensional variations are minimal and within typical mechanical tolerances. The bulk packaging format may require repackaging for automated assembly processes. REACH Affected status requires compliance verification for regulated markets.

Selection between the two substitutes depends on regulatory requirements, packaging compatibility with existing assembly processes, and temperature margin requirements for specific applications.

Frequently Asked Questions (FAQ)

Q: Can the Ohmite 825F20RE directly replace the 825F20R in existing designs?

A: Yes. The 825F20RE maintains identical electrical specifications (20 Ohms ±1%, 25W), thermal characteristics (±20ppm/°C, -55°C to 275°C), and mechanical form factor (aluminum housing, flanged mounting, solder lugs). The primary difference is product status (active versus obsolete) and packaging format (tray versus original packaging).

Q: What is the significance of the operating temperature range difference between the 825F20R and RH02520R00FC02?

A: The 825F20R operates to 275°C while the RH02520R00FC02 operates to 250°C. For applications operating below 250°C, this difference is not functionally significant. Applications requiring operation above 250°C must use the 825F20R or 825F20RE.

Q: Are there packaging considerations when substituting these parts?

A: Yes. The 825F20R uses standard packaging, the 825F20RE uses tray packaging, and the RH02520R00FC02 uses bulk packaging. Tray and bulk formats may require repackaging or handling adjustments for automated assembly equipment. Verify compatibility with existing pick-and-place or manual assembly processes.

Q: How do RoHS and REACH compliance affect part selection?

A: The 825F20RE is ROHS3 compliant and REACH Unaffected, making it suitable for regulated markets with strict environmental requirements. The RH02520R00FC02 is RoHS non-compliant and REACH Affected, requiring compliance verification before use in regulated applications. The original 825F20R is RoHS non-compliant and REACH Unaffected.

Q: Are dimensional differences between substitutes significant?

A: Dimensional variations are minimal. The RH02520R00FC02 has a width of 1.080" versus 1.094" for the other parts, and a maximum seated height of 0.561" versus 0.556". These differences (approximately 0.014" and 0.005" respectively) are within standard mechanical tolerances and do not affect board-level integration for typical applications.