3JS 500-R Equivalent & Substitute Parts

Part Overview

The 3JS 500-R is a 500 mA slow-blow glass cartridge fuse manufactured by Bel Fuse Inc., rated for 350 V AC and 140 V DC operation. This component is designed for through-hole mounting in the 2AG form factor (5mm x 15mm axial configuration). The part maintains active product status with full RoHS3 compliance and international certifications including CE, CSA, and cURus approval. Substitute parts are identified when equivalent electrical ratings and mechanical compatibility can be maintained across the specified parameter range.

Substiute Parts

3JS 500-R

Bel Fuse Inc.In Stock: 16543JS 500-R Datasheet

Current PartRFQ

0209.500MXEP

LittelfuseIn Stock: 40630209.500MXEP Datasheet

SimilarRFQ

0230.500MXP

Littelfuse Inc.In Stock: 20010230.500MXP Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 3JS 500-R is determined by the following critical parameters:

• Current Rating: Must be 500 mA
• Fuse Type: Must be Cartridge, Glass
• Response Time: Must be Slow Blow
• Mounting Type: Must be Through Hole
• Voltage Rating - AC: Must be ≥ 350 V
• Voltage Rating - DC: Must be ≥ 140 V (where applicable)
• Operating Temperature Range: Must encompass -55°C ~ 125°C
• RoHS Compliance: Must maintain ROHS3 status
• Mechanical Compatibility: Physical dimensions and form factor must support direct replacement in existing circuit board layouts

Two substitute parts meet these criteria with varying degrees of parameter alignment. The 0209.500MXEP maintains identical current rating and voltage specifications with equivalent mechanical form factor. The 0230.500MXP provides functional substitution with reduced voltage ratings suitable for lower-voltage applications.

Parameter Comparison

Engineering Selection Recommendations

0209.500MXEP (Littelfuse 209 Series): This substitute maintains full electrical equivalence with the 3JS 500-R across all critical parameters. Both components share identical current rating (500 mA), AC voltage rating (350 V), response time (Slow Blow), and operating temperature range (-55°C ~ 125°C). The 2AG form factor ensures mechanical compatibility with existing through-hole mounting positions. Both parts carry ROHS3 compliance. The 0209.500MXEP holds CE and cULus certifications, providing regulatory coverage for most applications. This substitute is suitable for direct replacement in circuits where the 3JS 500-R is specified.

0230.500MXP (Littelfuse 230 Series): This substitute is applicable only in applications where the circuit voltage requirements do not exceed 250 V AC and 125 V DC. The reduced voltage ratings make this part unsuitable for circuits designed for the full 350 V AC / 140 V DC capability of the 3JS 500-R. The non-standard cartridge form factor may present mechanical compatibility considerations. This substitute is restricted to lower-voltage applications and should be selected only when circuit design parameters explicitly permit reduced voltage operation. Both parts maintain ROHS3 compliance and carry CE certification along with CSA and UL approvals.

Frequently Asked Questions (FAQ)

Q: Can the 0209.500MXEP directly replace the 3JS 500-R in all applications?

A: The 0209.500MXEP maintains electrical equivalence across current rating, AC voltage rating, response time, and operating temperature range. Both components use the 2AG form factor for through-hole mounting. Substitution is valid for applications operating within these specified parameters.

Q: What are the key differences between the 0209.500MXEP and 0230.500MXP?

A: The 0209.500MXEP maintains the full 350 V AC rating of the original 3JS 500-R, while the 0230.500MXP is rated for 250 V AC maximum. The 0230.500MXP uses a non-standard cartridge form factor compared to the standard 2AG package. The 0209.500MXEP is the preferred substitute for direct replacement; the 0230.500MXP is restricted to lower-voltage circuit applications.

Q: Are there certification differences between these parts?

A: The 3JS 500-R carries CE, CSA, and cURus approvals. The 0209.500MXEP carries CE and cULus approvals. The 0230.500MXP carries CE, CSA, and UL approvals. All three parts maintain ROHS3 compliance. Certification selection should align with the regulatory requirements of the target application.

Q: What is the significance of the melting I²t value differences?

A: The 3JS 500-R has a melting I²t of 1.6, while both Littelfuse substitutes have a melting I²t of 1.16. This parameter indicates the thermal energy required to melt the fuse element. The lower I²t value in the substitutes indicates faster thermal response under fault conditions. Circuit design should account for this difference if precise thermal coordination with other protective devices is required.

Q: Can the 0230.500MXP be used in a 350 V AC circuit?

A: No. The 0230.500MXP is rated for 250 V AC maximum. Using this component in a 350 V AC circuit exceeds its voltage rating and violates safe operating conditions. The 0209.500MXEP is the appropriate substitute for 350 V AC applications.

Q: Are all three parts RoHS compliant?

A: Yes. The 3JS 500-R, 0209.500MXEP, and 0230.500MXP all maintain ROHS3 compliance status.