Honeywell 21SM365 Snap Action Switch SPDT Equivalent & Substitute Parts

Part Overview

The Honeywell 21SM365 is a snap action switch with Single Pole Double Throw (SPDT) circuit configuration, rated for 5A at 250V AC and 30V DC. This switch features a round pin plunger actuator and chassis mount termination with solder lugs. The product is classified as obsolete, making equivalent and substitute parts necessary for ongoing system maintenance and new design implementations.

The 21SM365 operates with an on-momentary switch function and is designed for applications requiring reliable snap action switching with low operating force (85gf) and precise actuation characteristics. RoHS compliance and unlimited moisture sensitivity rating (MSL 1) support deployment in diverse industrial environments.

Substiute Parts

21SM365

Honeywell Sensing and Productivity SolutionsIn Stock: 109421SM365 Datasheet

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MBZ101A01C01X01

APEM Inc.In Stock: 741MBZ101A01C01X01 Datasheet

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MBZ101A01C02X01

APEM Inc.In Stock: 792MBZ101A01C02X01 Datasheet

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MS0850500F060S1A

E-SwitchIn Stock: 1035MS0850500F060S1A Datasheet

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MS0850500F080S1A

E-SwitchIn Stock: 1289MS0850500F080S1A Datasheet

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MS0850500F250S1A

E-SwitchIn Stock: 1435MS0850500F250S1A Datasheet

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MS0850500F295S1A

E-SwitchIn Stock: 732MS0850500F295S1A Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the Honeywell 21SM365 is determined by the following critical parameters:

Primary Compatibility Criteria:

• Circuit configuration: SPDT
• Switch function: On-Momentary
• Actuator type: Round Pin Plunger
• Mounting type: Chassis Mount
• Termination style: Solder Lug

Electrical Compatibility Criteria:

• Current rating: Minimum 5A AC
• Voltage rating AC: Minimum 250V
• Voltage rating DC: Minimum 30V (where applicable)

Mechanical Compatibility Criteria:

• Operating position: 0.330" (8.4mm) nominal
• Actuator engagement: Compatible with round pin plunger actuation

Compliance Criteria:

• RoHS compliance status
• MSL rating: 1 (Unlimited)

Substitute parts are grouped into two categories based on electrical ratings:

Category A - Higher Current Rating (10A AC): APEM Inc. MBZ101A01C01X01 and MBZ101A01C02X01 provide enhanced current capacity at 250V AC, suitable for applications requiring higher switching capacity while maintaining SPDT configuration and chassis mount design.

Category B - Matched Current Rating (5A AC): E-Switch MS series parts (MS0850500F060S1A, MS0850500F080S1A, MS0850500F250S1A, MS0850500F295S1A) maintain the 5A current rating with variations in operating force, accommodating different actuation requirements within the same electrical envelope.

Parameter Comparison

Engineering Selection Recommendations

For Direct Electrical Replacement (5A AC, 250V AC):

The E-Switch MS0850500 series provides direct electrical equivalence to the 21SM365 at 5A AC rating. Within this series, selection depends on required operating force:

• MS0850500F060S1A: Lowest operating force (60gf) for sensitive actuation applications
• MS0850500F080S1A: Moderate operating force (80gf), closest to original 85gf specification
• MS0850500F250S1A: Higher operating force (250gf) for robust actuation
• MS0850500F295S1A: Maximum operating force (295gf) for demanding mechanical environments

All E-Switch MS series parts are active products with ROHS3 compliance and unlimited MSL rating. Operating temperature range (-25°C to 85°C) is narrower than the original part; applications requiring -55°C operation require evaluation against specific use case requirements.

For Enhanced Current Capacity (10A AC, 250V AC):

The APEM Inc. MBZ101A01C01X01 and MBZ101A01C02X01 provide doubled current capacity (10A AC) while maintaining 250V AC voltage rating and SPDT configuration. These parts are suitable for applications where the original 5A rating is insufficient. Both variants are mechanically and electrically identical with identical operating characteristics. APEM parts feature significantly higher mechanical life (10,000,000 cycles) compared to the original specification (80,000 cycles).

Compliance Considerations:

All substitute parts maintain RoHS compliance (ROHS3 standard) and unlimited MSL rating, ensuring compatibility with modern manufacturing and environmental standards. APEM parts include REACH Unaffected status; E-Switch parts include REACH Unaffected status.

Temperature Range Limitations:

The 21SM365 operates across -55°C to 125°C. Substitute parts operate within narrower ranges: APEM parts (-40°C to 85°C) and E-Switch parts (-25°C to 85°C). Applications requiring full -55°C to 125°C operation must evaluate whether substitute parts meet thermal requirements.

Frequently Asked Questions (FAQ)

Q: Can the APEM MBZ101A01C01X01 or MBZ101A01C02X01 directly replace the Honeywell 21SM365?

A: Yes, for applications operating at 250V AC. Both APEM parts maintain SPDT circuit configuration, on-momentary function, round pin plunger actuation, chassis mount design, and solder lug termination. The primary difference is increased current capacity (10A AC versus 5A AC). Operating temperature range is reduced (-40°C to 85°C versus -55°C to 125°C). Verify application temperature requirements before substitution.

Q: What is the difference between the E-Switch MS0850500F060S1A, MS0850500F080S1A, MS0850500F250S1A, and MS0850500F295S1A?

A: These four E-Switch parts are electrically and mechanically identical except for operating force and release force values. Operating force varies from 60gf (F060) to 295gf (F295). Select based on required actuation force for your specific mechanical application. All maintain 5A AC at 125V AC rating and identical mechanical life (1,000,000 cycles).

Q: Why do E-Switch parts specify 125V AC instead of 250V AC?

A: E-Switch MS0850500 series is rated for 125V AC maximum. Applications requiring 250V AC operation must use APEM MBZ101 series parts. Verify your application voltage requirement before selection.

Q: Are the operating position differences between 0.330" (8.4mm) and 0.335" (8.5mm) significant?

A: The difference of 0.005" (0.1mm) is within typical mechanical tolerance for snap action switch applications. Both dimensions accommodate standard round pin plunger actuation. Verify mechanical clearance in your specific application design.

Q: What is the significance of the higher mechanical life ratings in substitute parts?

A: APEM MBZ101 parts specify 10,000,000 mechanical cycles versus the original 80,000 cycles. E-Switch MS series specifies 1,000,000 cycles. Higher mechanical life ratings indicate extended service life under repeated actuation. Applications with high cycle counts benefit from these enhanced ratings.

Q: Can I use these substitute parts in DC applications?

A: The original 21SM365 is rated for 30V DC. APEM and E-Switch substitute parts do not specify DC voltage ratings. DC applications require confirmation that the substitute part is suitable for DC operation. Contact the manufacturer for DC compatibility verification.

Q: What packaging options are available?

A: Honeywell 21SM365 is supplied in standard packaging. APEM MBZ101 parts are supplied in Tray packaging. E-Switch MS0850500 series is supplied in Bulk packaging. Verify packaging requirements for your procurement and assembly processes.

Q: Are all substitute parts RoHS compliant?

A: Yes. The original 21SM365 is RoHS Compliant. All substitute parts (APEM MBZ101 and E-Switch MS0850500 series) are ROHS3 Compliant, meeting current RoHS standards.

Q: What is MSL rating and why is it important?

A: MSL (Moisture Sensitivity Level) rating indicates component sensitivity to moisture during storage and handling. All parts listed, including the original 21SM365 and all substitutes, carry MSL 1 (Unlimited) rating, indicating no moisture sensitivity restrictions. These parts can be stored and handled without special moisture control measures.