BZ-R173-A4 Equivalent & Substitute Parts

Part Overview

The BZ-R173-A4 is a snap action SPDT switch manufactured by Honeywell Sensing and Productivity Solutions. This chassis mount switch is rated for 15A at 125V AC with a round pin plunger actuator and screw terminal connections. The product is classified as obsolete, making equivalent and substitute parts necessary for ongoing applications and new designs requiring similar electrical and mechanical characteristics.

Substiute Parts

BZ-R173-A4

Honeywell Sensing and Productivity SolutionsIn Stock: 1144BZ-R173-A4 Datasheet

Current PartRFQ

A-20GD-B7-K

Omron Automation and SafetyIn Stock: 1168A-20GD-B7-K Datasheet

SimilarRFQ

Z-15GD-B7-K

Omron Automation and SafetyIn Stock: 951Z-15GD-B7-K Datasheet

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Z-15GD55-B7-K

Omron Automation and SafetyIn Stock: 1065Z-15GD55-B7-K Datasheet

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Z-15GS55-B7-K

Omron Automation and SafetyIn Stock: 902Z-15GS55-B7-K Datasheet

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Z-15H2-B

Omron Automation and SafetyIn Stock: 1146Z-15H2-B Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the BZ-R173-A4 is determined by the following critical parameters:

Primary Compatibility Criteria:

• Circuit configuration: SPDT
• Switch function: On-Momentary
• AC voltage rating: 125V minimum
• AC current rating: 15A minimum
• Actuator type: Round pin plunger
• Mounting type: Chassis mount
• Termination style: Screw terminal

Substitute Parts Identified:

Group 1 - Direct Current Rating Match (15A AC):

• Z-15GD-B7-K (Omron)
• Z-15GD55-B7-K (Omron)
• Z-15GS55-B7-K (Omron)

These parts maintain the 15A AC current rating and meet all primary compatibility criteria. All are active products with current manufacturing status.

Group 2 - Higher Current Rating (20A AC):

• A-20GD-B7-K (Omron)

This part exceeds the current requirement at 20A AC, providing additional capacity while maintaining all other critical parameters. Suitable for applications where higher current capability is beneficial.

Group 3 - Lower Current Rating (10A AC):

• Z-15H2-B (Omron)

This part operates at 10A AC, below the original specification. Suitable only for applications where the actual load current does not exceed 10A AC.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (15A AC Rating):

Z-15GD-B7-K is the primary equivalent substitute. This Omron part maintains identical AC current and voltage ratings, matching the mechanical life specification of 20,000,000 cycles. The part is active in production with RoHS3 compliance. Operating temperature range is reduced to -25°C to 80°C compared to the original -55°C to 85°C specification.

For Enhanced Environmental Protection:

Z-15GD55-B7-K and Z-15GS55-B7-K both provide IP62 ingress protection, suitable for applications requiring sealed operation. Both maintain 15A AC rating and 20,000,000 cycle mechanical life. Operating temperature range is -15°C to 80°C. Z-15GD55-B7-K has fixed 540gf operating force, while Z-15GS55-B7-K offers 250-350gf operating force range.

For Higher Current Capacity:

A-20GD-B7-K provides 20A AC rating for applications requiring additional current margin. Mechanical life is reduced to 1,000,000 cycles. This part is suitable when load current may exceed 15A but remain below 20A.

For Lower Current Applications:

Z-15H2-B operates at 10A AC and is suitable only when actual circuit load does not exceed 10A. This part maintains 20,000,000 cycle mechanical life and -25°C to 80°C operating range.

Compliance Considerations:

All substitute parts are RoHS compliant. Z-15GD-B7-K and Z-15H2-B carry ROHS3 compliance. All parts are classified as EAR99 for export control purposes.

Frequently Asked Questions (FAQ)

Q: Can Z-15H2-B replace BZ-R173-A4 in all applications?

A: No. Z-15H2-B is rated for 10A AC, which is below the original 15A specification. Use this part only in applications where the actual load current does not exceed 10A AC.

Q: What is the primary difference between Z-15GD-B7-K and Z-15GD55-B7-K?

A: Both maintain 15A AC rating and 20,000,000 cycle life. Z-15GD55-B7-K provides IP62 ingress protection and has a fixed 540gf operating force. Z-15GD-B7-K provides IP00 protection with 250-350gf operating force range. Z-15GD55-B7-K is suitable for sealed or wet environments.

Q: Is A-20GD-B7-K a suitable substitute if my application uses 15A?

A: Yes, A-20GD-B7-K is electrically compatible at 15A AC since it is rated for 20A AC. However, mechanical life is reduced to 1,000,000 cycles compared to 20,000,000 cycles in the original part. Verify mechanical cycle requirements before selection.

Q: What is the impact of the reduced operating temperature range in substitute parts?

A: The original BZ-R173-A4 operates from -55°C to 85°C. Most Omron substitutes operate from -25°C to 80°C (or -15°C for IP62 variants). Confirm that your application temperature requirements fall within the substitute part's range before selection.

Q: Are all substitute parts available in the same packaging as the original?

A: The original BZ-R173-A4 packaging is not specified. All Omron substitute parts are supplied in bulk packaging. Verify packaging requirements for your procurement process.

Q: Can I use Z-15GS55-B7-K instead of Z-15GD55-B7-K?

A: Both parts have identical electrical ratings (15A AC, 125V), IP62 protection, and 20,000,000 cycle life. The primary difference is operating position: Z-15GD55-B7-K operates at 0.846" (21.5mm) while Z-15GS55-B7-K operates at 1.110" (28.2mm). Selection depends on mechanical space constraints and actuator travel requirements in your application.

Q: What does SPDT mean in the circuit configuration?

A: SPDT stands for Single Pole Double Throw. This configuration provides one moving contact that switches between two fixed contacts, enabling on-off switching with a single actuator.

Q: Are there DC voltage ratings for these switches?

A: The original BZ-R173-A4 does not specify DC ratings. Omron substitute parts provide DC ratings: A-20GD-B7-K (6A at 30V DC), Z-15GD-B7-K (6A at 30V DC), Z-15GD55-B7-K (6A at 30V DC), Z-15GS55-B7-K (6A at 30V DC), and Z-15H2-B (2A at 30V DC). Verify DC requirements separately if applicable to your application.