PLKB8321 Keylock Switch - Equivalent & Substitute Parts

Part Overview

The PLKB8321 is a 3-position keylock switch manufactured by APEM Inc., featuring SPDT circuit configuration with 500mA DC rating at 30V. This component is classified as obsolete, making identification of functionally equivalent alternatives necessary for ongoing system maintenance and new design implementations. The switch is designed for panel-mount applications with solder lug termination and operates across a temperature range of -20°C to 65°C.

Substiute Parts

PLKB8321

APEM Inc.In Stock: 1016PLKB8321 Datasheet

Current PartRFQ

Y1907U2C207NG

C&KIn Stock: 814Y1907U2C207NG Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the PLKB8321 is determined by the following critical parameters:

• Circuit Configuration & Positions: The main part operates as SPDT with 3 positions in On-On-Off configuration. Substitute parts must maintain 3-position keylock functionality with compatible switching logic.
• Current & Voltage Ratings: The 500mA DC at 30V specification establishes the minimum electrical capacity requirement. Substitutes must meet or exceed these ratings.
• Actuator & Removability: Flat key actuator with all-position key removability is essential for operational compatibility.
• Mounting & Termination: Panel mount configuration with solder lug termination must be preserved for mechanical and electrical integration.
• Panel Cutout Compatibility: The 16.00mm circular cutout dimension is a critical mechanical constraint.
• Environmental & Compliance: Operating temperature range, RoHS3 compliance, and MSL rating must be maintained or improved.

The substitute part Y1907U2C207NG from C&K is evaluated against these parameters to determine functional equivalence within the constraints of available component specifications.

Parameter Comparison

Engineering Selection Recommendations

The Y1907U2C207NG from C&K presents a functionally related alternative to the obsolete PLKB8321, with the following engineering considerations:

Advantages of Substitution:

• Active product status ensures ongoing availability and supply chain continuity
• Current rating of 4A significantly exceeds the 500mA requirement, providing operational margin
• Identical RoHS3 compliance and MSL rating maintain regulatory and environmental standards
• Solder lug termination and flat key actuator preserve electrical and mechanical interface compatibility

Critical Limitations:

• Panel cutout diameter increases from 16.00mm to 19.30mm, requiring mechanical redesign of the mounting panel
• DC voltage rating of 28V is marginally below the 30V specification of the original part
• Circuit configuration changes from SPDT to SP3T, altering switching topology from On-On-Off to On-On-On
• Angle of throw reduces from 180° to 90°, affecting operational ergonomics and mechanical space requirements

Selection Criteria: Substitution is viable only when the application can accommodate the larger panel cutout, accept the reduced throw angle, and function with the SP3T On-On-On switching behavior. Applications requiring exact electrical and mechanical compatibility with the original PLKB8321 specification should pursue alternative sourcing strategies or component redesign.

Frequently Asked Questions (FAQ)

Q: Can the Y1907U2C207NG directly replace the PLKB8321 without modifications?

A: No. The substitute requires panel cutout enlargement from 16.00mm to 19.30mm diameter. Additionally, the switching function changes from On-On-Off to On-On-On, which may alter circuit behavior depending on application logic.

Q: What is the significance of the circuit configuration difference (SPDT vs. SP3T)?

A: SPDT (Single Pole Double Throw) provides two switching paths with one common terminal. SP3T (Single Pole Triple Throw) provides three switching paths with one common terminal. This fundamental difference affects how the switch integrates into control circuits and may require circuit redesign.

Q: Is the 28V DC rating of the substitute acceptable for a 30V application?

A: The 28V rating is marginally below the original 30V specification. Component selection should verify that the application's actual operating voltage does not exceed 28V DC to ensure reliable operation and component longevity.

Q: What are the mechanical implications of the 90° throw angle versus 180°?

A: The reduced throw angle affects the physical space required for switch actuation and may impact user interface ergonomics. Panel layout and access considerations must be evaluated for the specific application.

Q: Are both parts RoHS3 compliant?

A: Yes. Both the PLKB8321 and Y1907U2C207NG are ROHS3 compliant, ensuring compatibility with regulatory requirements for restricted substances.

Q: What is the packaging difference between these parts?

A: The PLKB8321 is supplied in standard packaging, while the Y1907U2C207NG is supplied in tray packaging. This affects handling, storage, and integration into automated assembly processes.

Q: Can the substitute handle higher current loads than the original?

A: Yes. The Y1907U2C207NG is rated for 4A (AC/DC) compared to the PLKB8321's 500mA DC rating. This provides an 8x current capacity margin, suitable for applications requiring higher switching capacity.