Littelfuse 0RLS020.T Fuse Cartridge - Equivalent & Substitute Parts

Part Overview

The Littelfuse 0RLS020.T is a 20A 600VAC fast-blow cartridge fuse from the POWR-GARD® RLS series, designed for electrical and industrial applications requiring holder-mounted protection. This part is classified as obsolete, making identification of compatible substitutes essential for system maintenance and component replacement. The substitute part maintains the same current rating, voltage specification, and physical dimensions while offering enhanced performance characteristics and active product status.

Substiute Parts

0RLS020.T

Littelfuse Inc.In Stock: 9370RLS020.T Datasheet

Current PartRFQ

KLSR020.T

Littelfuse Inc.In Stock: 734KLSR020.T Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The KLSR020.T qualifies as a direct substitute based on the following critical parameters:

• Current Rating Match: Both parts are rated at 20A
• AC Voltage Match: Both parts are rated at 600 VAC
• Physical Compatibility: Identical cartridge dimensions (0.811" Dia x 5.000" L) ensure mechanical fit in existing holders
• Response Characteristic: Both employ fast-blow response time
• Mounting Compatibility: Both require the same holder-based installation method
• Approval Certifications: Both carry CE, CSA, and UL certifications

The KLSR020.T represents an enhanced alternative with additional DC voltage capability (250 VDC) and superior breaking capacity (200kA AC, 20kA DC versus 10kA), while maintaining full compatibility with applications designed for the 0RLS020.T.

Parameter Comparison

Engineering Selection Recommendations

The KLSR020.T is the manufacturer-recommended substitute for the obsolete 0RLS020.T. Selection should be based on the following engineering criteria:

For AC-only applications at 600 VAC, 20A: The KLSR020.T provides direct functional equivalence with identical current and voltage ratings, identical physical form factor, and identical response characteristics. The enhanced breaking capacity (200kA AC) provides superior fault protection margin compared to the original 10kA specification.

For applications requiring RoHS compliance: The KLSR020.T meets ROHS3 compliance requirements, whereas the 0RLS020.T does not. This distinction is critical for new designs or systems subject to regulatory compliance mandates.

For applications with potential DC exposure: The KLSR020.T's 250 VDC rating provides additional operational flexibility beyond the AC-only specification of the original part.

Certification alignment: Both parts maintain identical approval agency certifications (CE, CSA, UL), ensuring no regulatory gaps in substitution.

Frequently Asked Questions (FAQ)

Q: Can the KLSR020.T be used as a direct replacement for the 0RLS020.T in existing equipment?

A: Yes. The KLSR020.T is mechanically and electrically compatible for AC applications at 600 VAC, 20A. Identical physical dimensions ensure proper fit in existing holders. Identical current rating, voltage rating, and response time ensure functional equivalence in AC circuits.

Q: What is the difference between Class H and Class RK1 fuses?

A: Class designation indicates the fuse's performance characteristics and breaking capacity. The KLSR020.T's RK1 classification provides a breaking capacity of 200kA AC, compared to the 0RLS020.T's Class H specification of 10kA. Both classes are suitable for industrial and electrical applications; the RK1 classification offers enhanced fault protection capability.

Q: Does the KLSR020.T's additional 250 VDC rating affect its use in 600 VAC AC applications?

A: No. The 250 VDC rating is an additional capability that does not impact AC performance. The part maintains full 600 VAC AC rating and fast-blow response time identical to the original specification.

Q: Are there any packaging differences between these parts?

A: The 0RLS020.T packaging is listed as non-standard, while the KLSR020.T is packaged in boxes. Both parts use identical cartridge form factors and require the same holder-based mounting. Packaging differences do not affect electrical or mechanical compatibility.

Q: Why is RoHS compliance status different between these parts?

A: The 0RLS020.T predates RoHS3 requirements and is marked as non-compliant. The KLSR020.T, as an active product, meets current ROHS3 compliance standards. For new installations or systems subject to environmental regulations, the KLSR020.T is the appropriate selection.