308NPC25K Equivalent & Substitute Parts Reference

Part Overview

The Honeywell Sensing and Productivity Solutions 308NPC25K is a 25k Ohm, 1/2W conductive plastic linear panel mount potentiometer with PC pin termination. This component is classified as obsolete, necessitating identification of equivalent substitute parts for ongoing applications and new designs. The 308NPC series potentiometer features a 1-gang configuration with side adjustment and slotted actuator design, suitable for panel-mounted applications requiring linear resistance variation.

Substiute Parts

308NPC25K

Honeywell Sensing and Productivity SolutionsIn Stock: 1240308NPC25K Datasheet

Current PartRFQ

91C1A-D24-B17L

Bourns Inc.In Stock: 127591C1A-D24-B17L Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 308NPC25K is determined by the following critical parameters:

Mandatory Matching Parameters:

• Resistance value: 25k Ohm
• Resistive material: Conductive Plastic
• Termination style: PC Pins
• Mounting type: Panel Mount
• Number of gangs: 1
• Taper: Linear
• Bushing thread: 1/4-32
• Number of turns: 1.0

Allowable Variation Parameters:

• Power rating: Substitute must equal or exceed 0.5W
• Tolerance: Substitute tolerance may differ from ±10%
• Rotation angle: Substitute rotation may vary (295° to 300° acceptable)
• Actuator type: May differ (slotted to round acceptable)
• Body size: May differ within panel mount constraints
• Product status: Active status preferred for obsolete parts

The Bourns Inc. 91C1A-D24-B17L meets all mandatory matching parameters and exceeds power rating requirements, qualifying as a direct substitute.

Parameter Comparison

Engineering Selection Recommendations

The Bourns Inc. 91C1A-D24-B17L potentiometer is a qualified substitute for the obsolete Honeywell 308NPC25K based on the following engineering criteria:

Functional Equivalence: Both components provide 25k Ohm linear resistance with identical electrical characteristics for standard potentiometer applications. The 91C1A-D24-B17L exceeds the power rating requirement (1W versus 0.5W), providing additional thermal margin.

Compliance Status: The 308NPC25K is RoHS Compliant. The 91C1A-D24-B17L is ROHS3 Compliant, meeting current regulatory requirements. Both components carry EAR99 ECCN classification and identical HTSUS codes (8533.40.8070).

Product Availability: The 308NPC25K is obsolete with limited inventory (1149 pcs). The 91C1A-D24-B17L is active status with current production availability (1217 pcs in stock), ensuring long-term supply chain continuity.

Physical Integration: Identical bushing thread (1/4-32), actuator length (19.05mm), and actuator diameter (3.18mm) ensure direct mechanical compatibility in existing panel mount installations. The round actuator on the substitute differs from the slotted actuator on the original part; this represents a functional design change requiring evaluation of adjustment mechanism compatibility in the specific application.

Tolerance Consideration: The substitute part tolerance (±20%) is wider than the original (±10%). Applications requiring tighter tolerance control must evaluate this parameter against circuit design specifications.

Frequently Asked Questions (FAQ)

Q: Can the 91C1A-D24-B17L directly replace the 308NPC25K in existing designs?

A: The 91C1A-D24-B17L is electrically and mechanically compatible for panel mount applications. The primary consideration is the actuator type change from slotted to round. If the application uses a slotted adjustment tool or requires specific actuator geometry, mechanical compatibility must be confirmed. The identical bushing thread and actuator dimensions support direct mounting.

Q: What is the significance of the tolerance difference (±10% versus ±20%)?

A: The 308NPC25K specifies ±10% tolerance, while the 91C1A-D24-B17L specifies ±20%. For applications where the potentiometer functions as a precision component (such as calibration or measurement circuits), the wider tolerance of the substitute may introduce additional circuit variation. For general-purpose applications, this difference is typically acceptable.

Q: Why is the power rating higher on the substitute part (1W versus 0.5W)?

A: The 91C1A-D24-B17L is rated for 1W continuous power dissipation, compared to the 0.5W rating of the 308NPC25K. This higher rating provides additional thermal capacity and is fully compatible with applications designed for 0.5W operation. No circuit modification is required.

Q: Are there packaging differences between these parts?

A: The 308NPC25K is supplied in standard packaging (not specified). The 91C1A-D24-B17L is supplied in Tray packaging. Both are panel mount potentiometers with identical termination (PC Pins), so packaging format does not affect circuit integration.

Q: What is the rotation angle difference (295° versus 300°)?

A: The 308NPC25K provides 295° of rotation, while the 91C1A-D24-B17L provides 300°. This 5° difference is negligible for standard potentiometer applications and does not affect functional performance or mechanical fit.

Q: Are both parts RoHS compliant?

A: Yes. The 308NPC25K is RoHS Compliant. The 91C1A-D24-B17L is ROHS3 Compliant, which represents current RoHS directive compliance. Both parts meet environmental regulatory requirements for electronic component manufacturing and use.

Q: What is the temperature coefficient specification for the substitute?

A: The 91C1A-D24-B17L specifies a temperature coefficient of ±1000ppm/°C. The 308NPC25K does not provide a temperature coefficient specification in the available data. For applications requiring temperature stability analysis, the substitute's temperature coefficient should be evaluated against circuit performance requirements across the operating temperature range.