Honeywell 21SM35 Snap Action Switch SPDT Equivalent & Substitute Parts

Part Overview

The Honeywell 21SM35 is an active-status snap action switch with SPDT (Single Pole Double Throw) circuit configuration, rated for 5A at 250V AC and 30V DC. This chassis-mount switch features a round pin plunger actuator with solder lug termination and is designed for on-momentary switching applications. The part operates across an extended temperature range of -55°C to 125°C with 80,000 mechanical cycles rated life.

Equivalent and substitute parts are identified based on matching core electrical and mechanical parameters: SPDT circuit configuration, 5A current rating, chassis mount construction, round pin plunger actuation, solder lug termination, and on-momentary switch function. Substitute parts from E-Switch are available with comparable mechanical characteristics and operational specifications.

Substiute Parts

21SM35

Honeywell Sensing and Productivity SolutionsIn Stock: 97121SM35 Datasheet

Current PartRFQ

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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Key Parameters

Substitute Part Grouping Explanation

Substitute parts are identified from the E-Switch MS series based on the following matching criteria:

Mandatory Matching Parameters:

• SPDT circuit configuration
• 5A current rating (AC)
• Round pin plunger actuator type
• Chassis mount construction
• Solder lug termination
• On-momentary switch function
• Active product status
• RoHS compliance

Variable Parameters Across Substitutes: The E-Switch MS0850500 series substitutes differ in operating force specification (60gf, 80gf, or 250gf), which determines actuation sensitivity. All three substitute models maintain identical mechanical life (1,000,000 cycles), operating position (0.335" / 8.5mm), and pretravel (0.043" / 1.1mm) characteristics.

Voltage Consideration: E-Switch substitutes are rated for 125V AC maximum, which is lower than the Honeywell 21SM35 rating of 250V AC. Substitution is valid only for applications operating at or below 125V AC.

Parameter Comparison

Engineering Selection Recommendations

Substitution Validity: E-Switch MS0850500 series parts are valid substitutes for the Honeywell 21SM35 in applications where the maximum operating voltage does not exceed 125V AC. All substitute candidates maintain active product status and current RoHS3 compliance certification.

Operating Force Selection:

• MS0850500F060S1A (60gf): Lowest actuation force; suitable for applications requiring minimal operator effort or sensitive touch activation.
• MS0850500F080S1A (80gf): Moderate actuation force; closest operational characteristic to the Honeywell 21SM35 (198gf operating force).
• MS0850500F250S1A (250gf): Highest actuation force; suitable for applications requiring deliberate, resistant actuation to prevent accidental activation.

Temperature Range Consideration: The Honeywell 21SM35 operates across -55°C to 125°C, while E-Switch substitutes operate across -25°C to 85°C. Substitution is valid only for applications within the -25°C to 85°C range.

Mechanical Life: E-Switch substitutes provide 1,000,000 mechanical cycles, exceeding the Honeywell 21SM35 specification of 80,000 cycles, offering extended service life in equivalent applications.

Frequently Asked Questions (FAQ)

Q: Can the E-Switch MS0850500 series substitute for the Honeywell 21SM35 in all applications?

A: No. Substitution is valid only when the application operates at or below 125V AC and within the temperature range of -25°C to 85°C. The Honeywell 21SM35 is rated for 250V AC and -55°C to 125°C; applications requiring these extended specifications must use the original part.

Q: What is the primary difference between the three E-Switch substitute models?

A: The three E-Switch models differ in operating force: MS0850500F060S1A (60gf), MS0850500F080S1A (80gf), and MS0850500F250S1A (250gf). Operating force determines the physical effort required to actuate the switch. All other electrical and mechanical parameters remain identical across the three models.

Q: Are the E-Switch substitutes mechanically compatible with the Honeywell 21SM35 mounting footprint?

A: Both the Honeywell 21SM35 and E-Switch MS0850500 series feature chassis mount construction with round pin plunger actuators and solder lug termination. Operating position measurements are nearly identical (0.330" vs. 0.335"), indicating mechanical compatibility for standard chassis mount applications.

Q: Do the E-Switch substitutes meet the same compliance standards as the Honeywell 21SM35?

A: Both the Honeywell 21SM35 and E-Switch MS0850500 series are RoHS compliant (RoHS vs. ROHS3) and carry MSL 1 (Unlimited) ratings. E-Switch substitutes additionally carry REACH Unaffected status. Both manufacturers assign EAR99 ECCN classification and 8536.50.7000 HTSUS code.

Q: What is the impact of the lower voltage rating on substitution?

A: The E-Switch substitutes are rated for 125V AC maximum, compared to the Honeywell 21SM35 at 250V AC. In applications operating above 125V AC, the E-Switch substitutes cannot be used. For applications at or below 125V AC, the lower voltage rating does not impact substitution validity.

Q: How do the mechanical life ratings compare?

A: The Honeywell 21SM35 is rated for 80,000 mechanical cycles, while all E-Switch MS0850500 substitutes are rated for 1,000,000 mechanical cycles. This represents a 12.5-fold increase in rated mechanical life for the E-Switch substitutes, providing extended operational durability in equivalent applications.