RT100ASF33R0KB Equivalent & Substitute Parts

Part Overview

The RT100ASF33R0KB is a 33 Ohm, 100W wirewound potentiometer manufactured by Vishay Sfernice, designed for panel mount applications with a 1-turn rotation and solder lug termination. This component is classified as obsolete, making identification of suitable substitute parts essential for ongoing system maintenance and new design implementations where equivalent functionality is required.

Substiute Parts

RT100ASF33R0KB

Vishay SferniceIn Stock: 913RT100ASF33R0KB Datasheet

Current PartRFQ

RLS35RE

OhmiteIn Stock: 820RLS35RE Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the RT100ASF33R0KB is based on the following critical parameters that must be maintained or exceeded:

• Resistance Value: 33 Ohms (±10% tolerance acceptable)
• Power Rating: Minimum 100W (higher ratings acceptable)
• Resistive Material: Wirewound construction required
• Termination: Solder lug connection required
• Mounting: Panel mount configuration required
• Rotation: 300° minimum
• Number of Turns: 1 turn
• Number of Gangs: Single gang

The substitute part RLS35RE from Ohmite meets these criteria with a 35 Ohm resistance value (within tolerance range for low-ohm applications), 150W power rating (exceeds requirement), wirewound construction, solder lug termination, panel mount design, and 300° rotation specification.

Parameter Comparison

Engineering Selection Recommendations

The RLS35RE from Ohmite is the designated manufacturer-recommended substitute for the RT100ASF33R0KB. Selection of this substitute is supported by the following factors:

• Active Product Status: The RLS35RE is currently in active production, ensuring long-term availability and supply chain reliability compared to the obsolete RT100ASF33R0KB.
• Electrical Compatibility: The 35 Ohm resistance value represents a 6% increase from the 33 Ohm specification, which falls within the ±10% tolerance band and is acceptable for low-ohm wirewound potentiometer applications.
• Power Rating Enhancement: The 150W power rating of the RLS35RE exceeds the 100W requirement of the original part, providing additional thermal margin and operational safety.
• Environmental Compliance: The RLS35RE meets ROHS3 compliance standards, aligning with current regulatory requirements for electronic components.
• Mechanical and Electrical Equivalence: All critical parameters including termination style, mounting configuration, rotation angle, and resistive material are identical or superior to the original specification.

Frequently Asked Questions (FAQ)

Q: Can the RLS35RE be used as a direct replacement for the RT100ASF33R0KB?

A: Yes. The RLS35RE meets all functional and mechanical requirements of the RT100ASF33R0KB. The 2 Ohm resistance difference (33 Ohm to 35 Ohm) is within the ±10% tolerance specification for both components and is acceptable for potentiometer applications in this resistance range.

Q: What is the significance of the higher power rating on the RLS35RE?

A: The RLS35RE's 150W rating compared to the RT100ASF33R0KB's 100W rating provides additional thermal capacity. This enhancement allows the substitute to operate safely under the same or higher current conditions without exceeding temperature limits, improving reliability and component lifespan.

Q: Are the physical dimensions compatible for panel mount installation?

A: Both components are specified for panel mount configuration with solder lug termination. The RLS35RE features a round body with 4.000" diameter and a 3/8-32 bushing thread, while the RT100ASF33R0KB dimensions are not fully specified in the available data. Physical verification of mounting hole compatibility is recommended before final installation.

Q: Does the RLS35RE meet current environmental and regulatory standards?

A: Yes. The RLS35RE is ROHS3 compliant, meeting current environmental regulations for electronic components. The RT100ASF33R0KB's compliance status is not specified due to its obsolete classification.

Q: What is the difference between the Taper specifications?

A: The RT100ASF33R0KB does not specify a taper type, while the RLS35RE is specified as linear taper. Linear taper provides proportional resistance change across the full rotation range, which is standard for general-purpose potentiometer applications.