Honeywell 9HM1 Snap Action Switch - Equivalent & Substitute Parts

Part Overview

The Honeywell 9HM1 is a hermetically sealed snap action switch with SPDT (Single Pole Double Throw) configuration, rated for 500mA DC at 28V. This component is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and component procurement.

The 9HM1 features a lever-actuated straight actuator with chassis mount termination via solder lugs. Its sealed hermetic design provides environmental protection suitable for aerospace and industrial applications requiring reliable switching performance across an extended temperature range of -65°C to 121°C.

Due to its obsolete status, sourcing direct replacements requires evaluation of active production alternatives that maintain electrical and mechanical compatibility with the original design specifications.

Substiute Parts

9HM1

Honeywell Sensing and Productivity SolutionsIn Stock: 9649HM1 Datasheet

Current PartRFQ

1HM1

Honeywell Sensing and Productivity SolutionsIn Stock: 8311HM1 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the obsolete 9HM1 is determined by strict equivalence across the following critical parameters:

Electrical Compatibility:

• Circuit configuration (SPDT)
• Switch function (On-Momentary)
• Voltage rating (28V DC minimum)
• Sealing type (Hermetically sealed)

Mechanical Compatibility:

• Actuator type (Lever, straight)
• Mounting type (Chassis mount)
• Termination style (Solder lug)
• Operating force (198gf)
• Release force (28gf)
• Operating position (0.330" / 8.4mm)

Environmental & Compliance:

• Operating temperature range (-65°C to 121°C)
• RoHS compliance status
• Moisture sensitivity level (MSL 1)

The primary distinction between the 9HM1 and its substitute lies in current rating capacity. The 9HM1 is rated for 500mA DC, while substitute alternatives may offer higher current ratings. A higher current rating does not preclude substitution, as the component will operate within its design envelope at lower current levels. However, lower current ratings are not acceptable substitutes.

Parameter Comparison

Engineering Selection Recommendations

The Honeywell 1HM1 is the direct functional equivalent for the obsolete 9HM1. Both components are manufactured by Honeywell Sensing and Productivity Solutions within the HM series and share identical electrical, mechanical, and environmental specifications.

Substitution Basis:

The 1HM1 maintains all critical parameters required for direct replacement:

• Identical SPDT circuit configuration and on-momentary switching function
• Equivalent 28V DC voltage rating
• Matching mechanical characteristics (lever actuator, chassis mount, solder lug termination)
• Identical operating force, release force, and actuator travel specifications
• Equivalent operating temperature range (-65°C to 121°C)
• Identical hermetic sealing and environmental protection
• Matching RoHS compliance and MSL 1 moisture sensitivity rating

The 1HM1 offers a higher current rating of 5A DC compared to the 9HM1's 500mA rating. This increased capacity does not compromise compatibility; the component will operate safely at the lower current levels required by systems originally designed for the 9HM1.

Procurement Advantage:

The 1HM1 is classified as active production status, ensuring ongoing availability and supply chain reliability compared to the obsolete 9HM1.

Frequently Asked Questions (FAQ)

Q: Can the 1HM1 directly replace the 9HM1 in existing assemblies?

A: Yes. The 1HM1 is electrically and mechanically equivalent to the 9HM1. All functional parameters, mounting interfaces, and termination styles are identical. The higher current rating of the 1HM1 (5A versus 500mA) does not affect compatibility in applications designed for the 9HM1.

Q: What is the significance of the higher current rating on the 1HM1?

A: The 1HM1's 5A DC rating provides greater current-handling capacity than the 9HM1's 500mA rating. In applications requiring only 500mA or less, the 1HM1 will operate within its design envelope without performance degradation. The higher rating does not introduce incompatibility.

Q: Are there packaging differences between the 9HM1 and 1HM1?

A: The 9HM1 is supplied in standard packaging, while the 1HM1 is supplied in bulk packaging. Both components are identical in form, fit, and function. Packaging differences do not affect electrical or mechanical compatibility.

Q: Do both parts meet the same compliance standards?

A: Yes. Both the 9HM1 and 1HM1 are RoHS compliant and carry MSL 1 (Unlimited) moisture sensitivity ratings. Both are classified under ECCN EAR99 and HTSUS 8536.50.7000.

Q: Why is the 9HM1 obsolete while the 1HM1 remains in active production?

A: The 1HM1 represents the current production equivalent within the Honeywell HM series. The 9HM1 has been superseded by the 1HM1 in the manufacturer's product line. The 1HM1 provides identical functionality with enhanced current capacity and ongoing supply availability.

Q: Are there any thermal or environmental limitations when substituting the 1HM1 for the 9HM1?

A: No. Both components operate across the identical temperature range of -65°C to 121°C and feature hermetic sealing for equivalent environmental protection. No thermal or environmental limitations apply to substitution.