SL1021B500RG Gas Discharge Tube - Equivalent & Substitute Parts

Part Overview

The SL1021B500RG is a 3-pole gas discharge tube (GDT) rated for 500V DC spark-over voltage with 20kA impulse discharge current capacity. This component is designed for through-hole mounting and provides fail-short protection in surge suppression applications.

The SL1021B500RG is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production or field replacement requirements.

Substiute Parts

SL1021B500RG

Littelfuse Inc.In Stock: 846SL1021B500RG Datasheet

Current PartRFQ

SL1021B500RF

Littelfuse Inc.In Stock: 710SL1021B500RF Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SL1021B500RG is based on electrical and mechanical parameter equivalence within the SL1021B series. The substitute part must satisfy the following criteria:

• Voltage - DC Spark Over (Nominal): 500 V
• Impulse Discharge Current (8/20µs): 20000A (20kA)
• Number of Poles: 3
• Fail Short: Yes
• Mounting Type: Through Hole
• Package / Case: Axial Cylinder, 3 Lead (Radial Bend)
• RoHS Status: ROHS3 Compliant
• Moisture Sensitivity Level (MSL): 1 (Unlimited)

The SL1021B500RF meets all these criteria and is classified as an active product, making it a direct electrical and mechanical equivalent.

Parameter Comparison

Engineering Selection Recommendations

The SL1021B500RF is the direct substitute for the obsolete SL1021B500RG. Both parts are manufactured by Littelfuse Inc. within the same SL1021B series and share identical electrical and mechanical specifications.

The SL1021B500RF carries active product status, ensuring ongoing availability and manufacturer support. Both parts maintain ROHS3 compliance and identical environmental ratings (MSL 1 - Unlimited), confirming regulatory equivalence for applications requiring RoHS certification.

The primary difference between the two parts is packaging format: the SL1021B500RG is supplied in bulk, while the SL1021B500RF is supplied in trays. This packaging distinction does not affect electrical performance or mechanical compatibility in through-hole PCB applications.

Frequently Asked Questions (FAQ)

Q: Can the SL1021B500RF be used as a direct replacement for the SL1021B500RG?

A: Yes. The SL1021B500RF is electrically and mechanically equivalent to the SL1021B500RG. Both parts feature identical 500V DC spark-over voltage, 20kA impulse discharge current, 3-pole configuration, fail-short protection, and through-hole mounting with the same axial cylinder package. No circuit modifications are required.

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

A: The SL1021B500RG and SL1021B500RF differ only in product status and packaging format. The SL1021B500RG is obsolete and supplied in bulk packaging, while the SL1021B500RF is an active product supplied in tray packaging. All electrical and mechanical parameters are identical.

Q: Are there any compliance or certification differences?

A: No. Both parts are ROHS3 compliant and carry identical moisture sensitivity ratings (MSL 1 - Unlimited). They meet the same regulatory and environmental standards.

Q: Does the tray packaging of the SL1021B500RF affect PCB assembly compatibility?

A: No. Tray packaging is a supply format consideration only and does not affect the component's electrical performance, mechanical fit, or through-hole mounting compatibility on printed circuit boards.

Q: Why is the SL1021B500RG marked as obsolete?

A: Product obsolescence is determined by the manufacturer based on market demand and product lifecycle management. The SL1021B500RF remains in active production and serves the same functional requirements.