PMT840004F Gas Discharge Tube 400V 20kA 3 Pole Through Hole Equivalent & Substitute Parts

Part Overview

The PMT840004F is a Gas Discharge Tube (GDT) rated for 400V DC spark-over voltage with 20kA impulse discharge current capacity in a 3-pole through-hole configuration. This component is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and component procurement.

Gas Discharge Tubes serve as surge protection devices in electrical circuits, providing rapid voltage clamping during transient overvoltage events. The obsolete status of the PMT840004F necessitates sourcing of equivalent active-production alternatives that maintain identical electrical and mechanical specifications.

Substiute Parts

PMT840004F

Littelfuse Inc.In Stock: 1205PMT840004F Datasheet

Current PartRFQ

SL1021B400RF

Littelfuse Inc.In Stock: 1442SL1021B400RF Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the PMT840004F is determined by strict equivalence across the following critical parameters:

• Voltage Rating: 400V DC spark-over voltage (nominal)
• Discharge Current Capacity: 20kA impulse discharge current (8/20µs waveform)
• Pole Configuration: 3-pole architecture
• Fail Mode: Short-circuit failure characteristic
• Mounting and Package: Through-hole mounting with axial cylinder, 3-lead radial bend package geometry
• Regulatory Compliance: ROHS3 compliance and MSL 1 rating

The SL1021B400RF meets all specified parameters and represents a direct functional equivalent suitable for replacement applications.

Parameter Comparison

Engineering Selection Recommendations

The SL1021B400RF is the appropriate substitute for the obsolete PMT840004F. Both components are manufactured by Littelfuse Inc. and share identical electrical ratings, mechanical packaging, and regulatory compliance certifications.

The primary distinction is product status: the PMT840004F is obsolete while the SL1021B400RF maintains active production status. This ensures long-term component availability and supply chain continuity for new designs and system maintenance.

Both parts carry ROHS3 compliance and MSL 1 rating, confirming equivalent environmental and handling requirements. The through-hole mounting configuration and axial cylinder package geometry are identical, permitting direct board-level substitution without design modification.

Frequently Asked Questions (FAQ)

Q: Can the SL1021B400RF be used as a direct replacement for the PMT840004F?

A: Yes. The SL1021B400RF is electrically and mechanically equivalent to the PMT840004F across all specified parameters, including voltage rating, discharge current capacity, pole configuration, and package geometry. Direct substitution is permissible.

Q: What is the difference between these two part numbers?

A: The primary difference is product lifecycle status. The PMT840004F is obsolete, while the SL1021B400RF is in active production. Both components are manufactured by Littelfuse Inc. and meet identical electrical and mechanical specifications.

Q: Are there any packaging differences between these parts?

A: Both parts use identical packaging: Axial Cylinder, 3 Lead (Radial Bend) through-hole configuration. The SL1021B400RF is supplied in Tray packaging, while the PMT840004F packaging format is not specified in available data.

Q: Do both parts meet the same regulatory requirements?

A: Yes. Both the PMT840004F and SL1021B400RF are ROHS3 compliant with MSL 1 (Unlimited) moisture sensitivity rating. Regulatory compliance is equivalent.

Q: What is the inventory status for these parts?

A: The PMT840004F has 1106 pieces available as new original stock. The SL1021B400RF has 1420 pieces available as new original stock in active production.