MRPR-3-22-33 Equivalent & Substitute Parts

Part Overview

The MRPR-3-22-33 is a glass body reed switch manufactured by Littelfuse Inc., configured as a SPST-NO (Single Pole Single Throw - Normally Open) device. This component operates within a 22–33 AT (Ampere-Turn) range and is rated for 50W power dissipation with switching capabilities of 1.1A AC and 1.5A DC at 140V AC / 200V DC. The part features through-hole axial termination and operates across a temperature range of -40°C to 125°C.

The MRPR-3-22-33 is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain design continuity and ensure component availability for new production runs, repairs, and system upgrades.

Substiute Parts

MRPR-3-22-33

Littelfuse Inc.In Stock: 930MRPR-3-22-33 Datasheet

Current PartRFQ

MRPR-20-22-28

Littelfuse Inc.In Stock: 1944MRPR-20-22-28 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the MRPR-3-22-33 is determined by the following critical parameters:

Circuit Configuration: Both the main part and substitute must maintain SPST-NO topology to preserve switching behavior in the application.

Mounting and Termination: Through-hole axial termination is required for PCB compatibility and mechanical fit.

Switching Characteristics: Current and voltage ratings must meet or exceed the application requirements. The substitute MRPR-20-22-28 maintains identical switching current ratings (1.1A AC / 1.5A DC) and rated power (50W), with enhanced voltage ratings (265V AC / 250V DC).

Operate Range: The MRPR-20-22-28 operates within 22–28 AT, which overlaps with the lower portion of the MRPR-3-22-33 range (22–33 AT). This overlap ensures functional compatibility for applications within the 22–28 AT window.

Environmental and Compliance: Both parts are ROHS3 compliant and rated for industrial temperature ranges, ensuring regulatory and operational compatibility.

Parameter Comparison

Engineering Selection Recommendations

The MRPR-20-22-28 is the direct substitute for the obsolete MRPR-3-22-33. Both components are manufactured by Littelfuse Inc. and share identical circuit topology, switching current ratings, power dissipation, and mechanical form factor.

The MRPR-20-22-28 offers enhanced voltage ratings (265V AC / 250V DC versus 140V AC / 200V DC), providing greater margin in high-voltage applications. The operate range of 22–28 AT is compatible with applications requiring actuation within this window.

The MRPR-20-22-28 maintains active product status, ensuring long-term availability and supply chain continuity. Both parts are ROHS3 compliant and carry MSL-1 moisture sensitivity classification, meeting modern regulatory and environmental standards.

The primary design consideration is the operating temperature range: the MRPR-3-22-33 operates from -40°C, while the MRPR-20-22-28 operates from -20°C. Applications requiring operation below -20°C must evaluate alternative solutions.

Frequently Asked Questions (FAQ)

Q: Can the MRPR-20-22-28 directly replace the MRPR-3-22-33 in existing designs?

A: Yes, for applications operating within the 22–28 AT range and above -20°C. The MRPR-20-22-28 maintains identical switching current, power rating, and mechanical dimensions. Verify that your application does not require operation below -20°C or at the upper end of the 29–33 AT operate range.

Q: What is the difference in operate range between these parts?

A: The MRPR-3-22-33 operates across 22–33 AT, while the MRPR-20-22-28 operates across 22–28 AT. The substitute covers the lower portion of the original range. Applications requiring actuation between 29–33 AT must use the original part or identify alternative solutions.

Q: Are the voltage ratings compatible?

A: The MRPR-20-22-28 has higher voltage ratings (265V AC / 250V DC) compared to the MRPR-3-22-33 (140V AC / 200V DC). This provides additional safety margin and is suitable for applications at or below the original voltage specifications.

Q: Do both parts have identical physical dimensions?

A: Yes. Both components measure 2.230" (56.64mm) overall length with 0.112" diameter bodies. Through-hole axial termination is identical, ensuring direct PCB compatibility.

Q: What is the temperature operating range difference?

A: The MRPR-3-22-33 operates from -40°C to 125°C, while the MRPR-20-22-28 operates from -20°C to 125°C. Applications requiring operation below -20°C must retain the original part or source alternative components.

Q: Are both parts RoHS compliant?

A: Yes. Both the MRPR-3-22-33 and MRPR-20-22-28 are ROHS3 compliant with MSL-1 moisture sensitivity classification, meeting current regulatory requirements.

Q: Why is the MRPR-3-22-33 listed as obsolete?

A: The MRPR-3-22-33 has been discontinued by Littelfuse Inc. The MRPR-20-22-28 is the active replacement, offering improved voltage ratings and maintained availability for new production and field service applications.