SL18 2R508-B Inrush Current Limiter - Equivalent & Substitute Parts

Part Overview

The SL18 2R508-B is an inrush current limiter manufactured by Ametherm, designed to limit inrush current in power supply circuits. This component operates at 2.5 Ohms with ±20% tolerance and supports a steady-state maximum current of 8 A. The part is currently active in production with ROHS3 compliance and unlimited moisture sensitivity rating (MSL 1). Finding equivalent substitute parts may be necessary due to inventory availability, lead time requirements, or supply chain optimization.

Substiute Parts

SL18 2R508-B

AmethermIn Stock: 842SL18 2R508-B Datasheet

Current PartRFQ

B57238S0259M000

EPCOS - TDK ElectronicsIn Stock: 12729B57238S0259M000 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for inrush current limiters is determined by the following critical parameters:

• Resistance Value: Must match at 2.5 Ohms ±20% tolerance
• Steady State Current Rating: Must meet or exceed 8 A requirement
• Physical Dimensions: Diameter and lead spacing must be compatible with PCB layout and thermal management requirements
• Compliance Standards: RoHS3 compliance and REACH unaffected status required for regulatory alignment
• Product Status: Active production status ensures ongoing availability and support

The substitute part B57238S0259M000 meets all substitution criteria with equivalent electrical specifications and enhanced current rating capability.

Parameter Comparison

Engineering Selection Recommendations

Both the SL18 2R508-B and B57238S0259M000 are active production components with ROHS3 compliance and REACH unaffected status, meeting current regulatory requirements. The B57238S0259M000 offers a higher steady-state current rating of 8.4 A compared to 8 A, providing additional thermal margin in applications requiring sustained current operation. The substitute part features a smaller physical diameter (16.00mm vs 19.00mm) and slightly reduced lead spacing (7.50mm vs 7.80mm), which may require PCB layout verification for mechanical fit and thermal dissipation characteristics. Both components maintain identical resistance values and tolerance specifications, ensuring electrical equivalence in inrush current limiting applications.

Frequently Asked Questions (FAQ)

Q: Can B57238S0259M000 be used as a direct replacement for SL18 2R508-B?

A: Electrical substitution is valid based on matching resistance (2.5 Ohms ±20%) and current rating (8.4 A exceeds 8 A requirement). Physical dimensions differ; verify PCB layout compatibility before implementation.

Q: What are the key parameters that determine substitution eligibility?

A: Resistance value, tolerance, steady-state current rating, physical dimensions (diameter and lead spacing), RoHS compliance status, and product availability determine substitution eligibility for inrush current limiters.

Q: Does the smaller diameter of B57238S0259M000 affect thermal performance?

A: Thermal performance depends on application-specific factors including ambient temperature, PCB thermal design, and duty cycle. Physical dimensions must be verified against PCB layout and thermal management requirements.

Q: Are both parts compliant with current regulatory standards?

A: Both SL18 2R508-B and B57238S0259M000 are ROHS3 compliant and REACH unaffected, meeting current regulatory requirements for electronic component manufacturing and distribution.

Q: What is the significance of the higher current rating on the substitute part?

A: The B57238S0259M000 steady-state rating of 8.4 A exceeds the SL18 2R508-B requirement of 8 A, providing additional operational margin in sustained current applications.