Molex 2138672933 NTC Thermistor Ring Lug - Equivalent & Substitute Parts

Part Overview

The Molex 2138672933 is an NTC thermistor with a 30kΩ resistance at 25°C, configured as a ring lug connector for temperature sensing applications. This component features a 75mm lead wire length and operates across a -40°C to 150°C temperature range. The part is currently classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and component procurement.

Substiute Parts

2138672933

MolexIn Stock: 8242138672933 Datasheet

Current PartRFQ

2138652933

MolexIn Stock: 11192138652933 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for NTC thermistor ring lug assemblies is determined by the following parameters:

Primary Matching Criteria:

• Resistance value at 25°C: 30kΩ (exact match required)
• Resistance tolerance: ±2% (matching tolerance specification)
• Package configuration: Ring Lug (mechanical compatibility)
• Lead wire length: 75mm (form factor compatibility)
• Mounting type: Free Hanging (installation compatibility)

Secondary Compatibility Factors:

• B25/85 thermal coefficient value (thermal response characteristic)
• Operating temperature range (application suitability)
• Power dissipation rating (thermal handling capability)
• RoHS compliance status (regulatory requirement)

The Molex 2138652933 qualifies as a substitute based on matching primary criteria across resistance value, tolerance, package type, and lead wire length. Differences in B25/85 value, operating temperature range, and power dissipation represent functional variations that must be evaluated against specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

The Molex 2138652933 is the designated substitute for the obsolete 2138672933. Both components maintain ROHS3 compliance and share identical resistance specifications at 25°C with matching tolerance bands. The substitute part is currently in active production status with confirmed inventory availability (1061 units), whereas the original part is obsolete with limited stock (726 units).

Key differentiation factors include the operating temperature ceiling, where the substitute operates to 105°C compared to the original 150°C specification. The substitute also provides higher power dissipation capability at 150 mW versus 100 mW. The B25/85 thermal coefficient differs slightly (3982K versus 4020K), representing a minor variation in thermal response characteristics.

Selection between these parts should be based on application-specific temperature requirements and thermal dissipation demands. For applications requiring operation above 105°C, the original specification cannot be met by this substitute. For applications within the 105°C ceiling, the substitute provides equivalent functionality with the advantage of active production status and regulatory compliance.

Frequently Asked Questions (FAQ)

Q: Can the 2138652933 directly replace the 2138672933 in all applications?

A: Direct replacement is possible only when the application operating temperature does not exceed 105°C. The original part specification extends to 150°C. Verify your system's maximum operating temperature requirement before substitution.

Q: Are the resistance values identical between these parts?

A: Yes. Both parts specify 30kΩ resistance at 25°C with ±2% tolerance. This core parameter is matched between the main part and substitute.

Q: What is the significance of the B25/85 value difference?

A: The B25/85 thermal coefficient (4020K vs. 3982K) defines the thermistor's thermal response curve. This minor difference affects temperature measurement accuracy across the operating range. Evaluate whether your application's calibration can accommodate this variation.

Q: Are both parts RoHS compliant?

A: Yes. Both the 2138672933 and 2138652933 are ROHS3 compliant, meeting current regulatory requirements for electronic component manufacturing.

Q: Why is the original part obsolete?

A: The 2138672933 is classified as obsolete by Molex. The 2138652933 represents the active production alternative with equivalent core functionality and improved availability.

Q: Does the higher power dissipation rating of the substitute affect compatibility?

A: Higher power dissipation capability (150 mW vs. 100 mW) does not create incompatibility. This specification indicates the substitute can handle equal or greater thermal loads. Verify that your application's power dissipation requirements do not exceed the original 100 mW specification if thermal management is critical.

Q: Are the physical dimensions and mounting configurations identical?

A: Yes. Both parts feature 75mm lead wire length, ring lug package configuration, and free hanging mounting type, ensuring mechanical compatibility in existing installations.