Equivalent & Substitute Parts for Ohmite 810F30R

Part Overview

The Ohmite 810F30R is a 30 Ohms ±1% 10W wirewound chassis mount resistor from the Metal-Mite®89 series. This component is classified as obsolete, making identification of suitable alternatives essential for ongoing system support and new design implementations. The part features aluminum housing with flanged mounting and solder lug termination, designed for applications requiring precision resistance with moderate power dissipation in a compact form factor.

Substiute Parts

810F30R

OhmiteIn Stock: 1118810F30R Datasheet

Current PartRFQ

UAL50-30RF8

RiedonIn Stock: 1197UAL50-30RF8 Datasheet

MFR RecommendedRFQ

810F30RE

OhmiteIn Stock: 1015810F30RE Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 810F30R are identified based on strict electrical and mechanical parameter matching. The primary substitution criteria are:

Electrical Parameters: Resistance value (30 Ohms), tolerance (±1%), temperature coefficient (±20ppm/°C), and operating temperature range (-55°C to 275°C) must remain constant across all substitutes.

Mechanical Parameters: Wirewound composition, aluminum housing, flanged mounting feature, and solder lug termination are required for form-fit-function compatibility.

Power Rating Consideration: Substitutes may exceed the original 10W rating, as higher power-rated components remain functionally compatible in applications designed for lower power dissipation.

Two substitute parts meet these criteria:

1. 810F30RE (Ohmite) — Parametric equivalent with identical electrical and mechanical specifications; differs only in product status (Active vs. Obsolete) and RoHS compliance level.

2. UAL50-30RF8 (Riedon) — Manufacturer-recommended substitute with identical core electrical parameters and mechanical form factor; features enhanced power rating (50W) and additional functional features (current sense, flame proof, pulse withstanding, safety).

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Form-Fit-Function): The 810F30RE is the optimal choice for applications requiring identical physical dimensions and electrical performance. Both parts share the same footprint (0.750" L x 0.812" W, 0.400" seated height) and are electrically equivalent. The 810F30RE offers the advantage of Active product status and ROHS3 compliance, eliminating obsolescence risk.

For Enhanced Performance or Space-Constrained Designs: The UAL50-30RF8 provides a 50W power rating, enabling use in applications with higher thermal demands or transient current conditions. The increased physical dimensions (1.969" L x 1.142" W, 0.630" seated height) must be verified against available mounting space. This substitute includes additional functional features (current sense, flame proof, pulse withstanding, safety) suitable for demanding industrial or safety-critical applications.

Compliance Considerations: Both substitute parts are ROHS3 compliant with MSL rating of 1 (Unlimited), meeting modern environmental and reliability standards. The main part (810F30R) is RoHS non-compliant, making substitution advisable for new designs or systems requiring regulatory compliance.

Frequently Asked Questions (FAQ)

Q: Can the 810F30RE be used as a direct drop-in replacement for the 810F30R?

A: Yes. The 810F30RE is electrically and mechanically identical to the 810F30R. Both parts have the same resistance (30 Ohms ±1%), power rating (10W), temperature coefficient (±20ppm/°C), operating range (-55°C to 275°C), and physical dimensions (0.750" L x 0.812" W, 0.400" seated height). The primary difference is product status (Active vs. Obsolete) and RoHS compliance.

Q: What are the dimensional differences between the 810F30RE and UAL50-30RF8?

A: The 810F30RE maintains the original compact footprint of 0.750" L x 0.812" W with 0.400" seated height. The UAL50-30RF8 is larger at 1.969" L x 1.142" W with 0.630" seated height. Verify available mounting space before selecting the UAL50-30RF8.

Q: Why would I choose the UAL50-30RF8 over the 810F30RE?

A: The UAL50-30RF8 is selected when applications require higher power dissipation (50W vs. 10W), enhanced reliability features (flame proof, pulse withstanding, safety certification), or current sensing capability. The higher power rating provides thermal margin in demanding environments.

Q: Are all three parts electrically interchangeable?

A: Yes, for the core electrical function. All three parts deliver 30 Ohms ±1% with ±20ppm/°C temperature coefficient across the -55°C to 275°C operating range. The UAL50-30RF8's higher power rating does not affect electrical interchangeability; it only provides additional thermal capacity.

Q: What is the impact of the larger UAL50-30RF8 dimensions on circuit board layout?

A: The UAL50-30RF8 requires approximately 2.5 times more board space than the 810F30RE. Verify that the mounting location can accommodate the larger footprint (1.969" L x 1.142" W) and increased seated height (0.630"). Flanged mounting remains compatible across all three parts.

Q: Are there any compliance or certification differences between the substitutes?

A: Both the 810F30RE and UAL50-30RF8 are ROHS3 compliant with MSL rating 1 (Unlimited). The main part (810F30R) is RoHS non-compliant. For applications requiring environmental compliance, either substitute is suitable. The UAL50-30RF8 includes additional safety features (flame proof, safety certification) beneficial for regulated industries.