SL1024A400R Gas Discharge Tube - Equivalent & Substitute Parts

Part Overview

The SL1024A400R is a 3-pole gas discharge tube (GDT) rated for 400V DC spark-over voltage with 10kA impulse discharge current capacity. Designed for through-hole mounting in axial cylinder configuration, this component is used for overvoltage protection in industrial and telecommunications applications.

The SL1024A400R is classified as obsolete. Locating equivalent substitute parts is necessary to maintain design continuity and ensure component availability for new production runs, repairs, and system upgrades.

Substiute Parts

SL1024A400R

Littelfuse Inc.In Stock: 881SL1024A400R Datasheet

Current PartRFQ

SL1021A400R

Littelfuse Inc.In Stock: 2105SL1021A400R Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SL1024A400R is based on electrical and mechanical parameter equivalence. The following criteria determine direct substitutability:

• Voltage rating: 400V DC spark-over voltage (nominal)
• Discharge current capacity: 10kA impulse current (8/20µs waveform)
• Pole configuration: 3-pole architecture
• Mounting and package: Through-hole axial cylinder with 3 radial leads
• Fail mode: Non-shorting characteristic
• Environmental compliance: ROHS3 compliance and moisture sensitivity level 1

The SL1021A400R meets all these electrical and mechanical requirements and is classified as an active product, making it a direct equivalent for the obsolete SL1024A400R.

Parameter Comparison

Engineering Selection Recommendations

The SL1021A400R is the direct equivalent for the SL1024A400R. Both components are manufactured by Littelfuse Inc. and share identical electrical specifications (400V spark-over, 10kA discharge current) and mechanical configuration (3-pole through-hole axial cylinder).

The SL1021A400R holds active product status, ensuring ongoing availability and supply chain support. Both parts maintain ROHS3 compliance and identical moisture sensitivity ratings, confirming environmental and regulatory equivalence.

For applications currently using the SL1024A400R, the SL1021A400R provides direct functional replacement without circuit redesign or performance compromise.

Frequently Asked Questions (FAQ)

Q: Can the SL1021A400R be used as a direct replacement for the SL1024A400R?

A: Yes. Both components share identical electrical ratings (400V DC spark-over, 10kA impulse current), pole configuration (3-pole), mounting type (through-hole), and package geometry (axial cylinder with radial leads). No circuit modifications are required.

Q: What is the difference between the SL1024A and SL1021A series?

A: The SL1024A series is obsolete, while the SL1021A series is active. Both series share the same electrical and mechanical specifications for equivalent voltage and current ratings. The series designation change reflects product line evolution within Littelfuse's GDT portfolio.

Q: Are there packaging differences between these parts?

A: The SL1024A400R is supplied in standard packaging, while the SL1021A400R is supplied in tray packaging. Both use identical component geometry (axial cylinder, 3 radial leads) suitable for through-hole PCB assembly. Tray packaging is standard for active production components.

Q: Do both parts meet the same compliance standards?

A: Yes. Both the SL1024A400R and SL1021A400R are ROHS3 compliant with moisture sensitivity level 1 (unlimited). Both carry EAR99 ECCN classification and share the same HTSUS code (8536.30.8000).

Q: Is the SL1021A400R available in inventory?

A: The SL1021A400R is an active product with current manufacturing support. Availability should be confirmed through authorized Littelfuse distributors. The SL1024A400R, being obsolete, has limited remaining inventory.