Honeywell 308N25K Potentiometer - Equivalent & Substitute Parts

Part Overview

The Honeywell 308N25K is a 25k Ohm linear panel mount potentiometer rated at 0.5W/1/2W with conductive plastic resistive material and solder hook termination. This component is classified as obsolete, making identification of functionally equivalent substitutes essential for ongoing system maintenance and new design implementations where legacy specifications must be maintained.

The primary driver for substitute part identification is the obsolete product status, which restricts availability through standard distribution channels. Equivalent parts must maintain identical electrical performance and mechanical compatibility within the specified tolerance and operational parameters.

Substiute Parts

308N25K

Honeywell Sensing and Productivity SolutionsIn Stock: 988308N25K Datasheet

Current PartRFQ

RV6NAYSD253A

Precision Electronics CorporationIn Stock: 1300RV6NAYSD253A Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute part identification for the 308N25K is based on strict equivalence across all critical electrical and mechanical parameters. The following parameters determine substitution eligibility:

Electrical Parameters (Non-Negotiable):

• Resistance value: 25k Ohm
• Tolerance: ±10%
• Power rating: 0.5W minimum
• Taper characteristic: Linear
• Number of turns: 1.0

Mechanical Parameters (Non-Negotiable):

• Mounting configuration: Panel Mount
• Bushing thread specification: 1/4-32
• Actuator diameter: 0.125" (3.18mm)
• Rotation angle: 295°
• Number of gangs: 1
• Built-in switch: None

Acceptable Variations:

• Resistive material composition (conductive plastic or carbon film)
• Termination style (solder hook or solder lug)
• Actuator length (within mechanical envelope constraints)
• Body shape and size (within panel cutout compatibility)
• Product status (active preferred for availability)

The RV6NAYSD253A meets all critical substitution criteria while offering improved availability through active product status.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: RV6NAYSD253A

The RV6NAYSD253A from Precision Electronics Corporation is the qualified equivalent for the obsolete Honeywell 308N25K. Selection of this substitute is based on the following engineering factors:

Electrical Equivalence: All critical electrical parameters match exactly: 25k Ohm resistance, ±10% tolerance, 0.5W/1/2W power rating, linear taper, and 1.0 turn configuration. The carbon resistive material provides functionally equivalent performance to the conductive plastic material in the original part.

Mechanical Compatibility: The RV6NAYSD253A maintains identical mounting specifications (panel mount with 1/4-32 bushing thread), actuator diameter (0.125"), and rotation angle (295°). The slightly longer actuator (0.875" vs. 0.750") and round body shape (vs. square) represent acceptable mechanical variations that do not compromise panel integration or operational function.

Compliance and Availability: The RV6NAYSD253A holds active product status with ROHS3 compliance certification, ensuring long-term availability and regulatory alignment. The original 308N25K obsolete status creates supply chain risk that this substitute eliminates.

Termination Consideration: The transition from solder hook to solder lug termination requires PCB design verification to confirm pad compatibility. Both termination styles are standard in potentiometer applications and present no functional limitation.

Frequently Asked Questions (FAQ)

Q: Can the RV6NAYSD253A be used as a direct replacement for the 308N25K in existing designs?

A: Yes, the RV6NAYSD253A meets all critical electrical and mechanical specifications for direct substitution. PCB termination pads must accommodate solder lug connection instead of solder hook. Panel cutout dimensions should be verified for the round body profile (0.510" diameter vs. 0.500" square).

Q: What is the difference between conductive plastic and carbon resistive materials in potentiometers?

A: Both materials provide linear taper characteristics and meet the specified electrical parameters. Carbon film potentiometers typically offer lower cost and are widely available. Conductive plastic potentiometers may provide smoother operation in some applications. For this 25k Ohm, 0.5W application, both materials deliver equivalent performance.

Q: Does the longer actuator length (0.875" vs. 0.750") affect panel mounting?

A: The actuator length difference does not affect the mounting interface, which is determined by the bushing thread (1/4-32) and body dimensions. The longer actuator provides extended reach above the panel surface. Verify that the control knob or coupling mechanism accommodates the additional length.

Q: Are there any compliance differences between the two parts?

A: Both parts are RoHS compliant. The 308N25K carries RoHS Compliant certification, while the RV6NAYSD253A carries ROHS3 Compliant certification. ROHS3 represents the current regulatory standard and provides enhanced compliance assurance.

Q: What is the impact of the body shape change from square to round?

A: The body shape change from square (0.500" x 0.500") to round (0.510" diameter) requires verification of the panel cutout dimensions. The round profile may require a circular cutout instead of a square cutout. Mechanical envelope compatibility must be confirmed before implementation.

Q: Is the RV6NAYSD253A the only available substitute?

A: Based on the provided substitute list, the RV6NAYSD253A is the identified equivalent part. Additional substitutes may exist in the market; however, any alternative must meet all critical parameters listed in the Key Parameters section to ensure functional equivalence.

Q: What inventory considerations apply to this substitution?

A: The 308N25K shows 974 pieces in stock (obsolete status), while the RV6NAYSD253A shows 1253 pieces in stock (active status). For new designs or long-term production, the active status of the RV6NAYSD253A provides superior supply chain continuity.