SW3821/A/UC Equivalent & Substitute Parts

Part Overview

The SW3821/A/UC is a rocker switch manufactured by NKK Switches, classified as a DPST (Double Pole Single Throw) on-off switch rated for 30A at 125V AC/DC operation. This component features panel mount installation with a flange, screw terminal connections, and a white concave actuator. The part is currently listed as obsolete, making identification of equivalent and substitute parts essential for ongoing maintenance, repair, and new design applications where this switch specification remains functionally required.

Substiute Parts

SW3821/A/UC

NKK SwitchesIn Stock: 1002SW3821/A/UC Datasheet

Current PartRFQ

SW3821

NKK SwitchesIn Stock: 1434SW3821 Datasheet

SimilarRFQ

SW3821/UC

NKK SwitchesIn Stock: 1148SW3821/UC Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SW3821/A/UC is determined by strict equivalence across the following critical parameters: circuit configuration (DPST), switch function (On-Off), current rating (30A AC/DC), voltage ratings (125V AC / 30V DC), mounting type (Panel Mount, Flange), actuator type (Concave Standard V), actuator color (White), termination style (Screw Terminal), operating temperature range (-10°C to 70°C), mechanical life (50,000 cycles), electrical life (25,000 cycles), and regulatory approvals (CSA, UL).

The substitute parts identified—SW3821 and SW3821/UC—meet all these criteria. Both are manufactured by NKK Switches and maintain identical electrical and mechanical specifications. The primary distinction lies in product status: SW3821/A/UC and SW3821/UC are obsolete, while SW3821 is active. All three parts share the same base product number designation and are fully interchangeable from an engineering standpoint.

Parameter Comparison

Engineering Selection Recommendations

For new designs and ongoing applications, SW3821 is the preferred selection due to its active product status with NKK Switches, ensuring continued availability and supply chain reliability. This part maintains full compliance with CSA and UL certifications and meets ROHS3 requirements.

SW3821/UC and SW3821/A/UC are functionally equivalent alternatives and remain suitable for replacement applications in existing systems where the SW3821/A/UC is currently installed. However, both are classified as obsolete and should be considered secondary options for new procurement due to potential long-term availability constraints.

All three parts are electrically and mechanically interchangeable, with no design modifications required when substituting between them.

Frequently Asked Questions (FAQ)

Q: Can SW3821 be used as a direct replacement for SW3821/A/UC?

A: Yes. SW3821 is a direct equivalent. Both parts share identical electrical ratings (30A at 125V AC/DC), circuit configuration (DPST), mounting specifications (Panel Mount, Flange), actuator characteristics (Concave, White), and termination style (Screw Terminal). No circuit modifications or mechanical adjustments are required.

Q: What is the difference between SW3821/A/UC, SW3821/UC, and SW3821?

A: All three parts are manufactured by NKK Switches and are electrically and mechanically identical. The primary difference is product status: SW3821 is active, while SW3821/A/UC and SW3821/UC are obsolete. The suffix designations (/A/UC and /UC) represent packaging or configuration variants that do not affect functional performance.

Q: Why is SW3821/A/UC listed as obsolete?

A: Obsolete status indicates that NKK Switches has discontinued active production and support for this specific part number variant. SW3821 remains the active equivalent and is the recommended selection for new applications.

Q: Are there any compliance or certification differences between these parts?

A: No. All three parts carry identical CSA and UL approvals and maintain ROHS3 compliance. Regulatory and safety certifications are equivalent across all variants.

Q: What inventory status should I consider when selecting a substitute?

A: Current inventory levels are: SW3821/A/UC (949 pcs), SW3821 (1,388 pcs), and SW3821/UC (1,121 pcs). For long-term supply assurance, SW3821 is recommended due to its active status and higher available inventory.