Grayhill 78B09 DIP Switch SPST 9-Position Equivalent & Substitute Parts

Part Overview

The Grayhill 78B09 is a slide-actuated DIP switch with SPST (Single Pole Single Throw) configuration, rated for 150mA at 30VDC. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement. The 78B09 features a 9-position through-hole configuration with gold-plated copper alloy contacts and operates across the industrial temperature range of -40°C to 85°C. Substitute parts must maintain functional compatibility within the electrical and mechanical constraints of the original design.

Substiute Parts

78B09

Grayhill Inc.In Stock: 98178B09 Datasheet

Current PartRFQ

78B09T

Grayhill Inc.In Stock: 101378B09T Datasheet

DirectRFQ

206-9

CTS ElectrocomponentsIn Stock: 1143206-9 Datasheet

DirectRFQ

BD09

C&KIn Stock: 1810BD09 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 78B09 is determined by strict adherence to the following electrical and mechanical parameters:

Primary Compatibility Criteria:

• Circuit configuration must be SPST
• Number of positions must be 9
• Mounting type must be through-hole
• Pitch must be 0.100" (2.54mm)
• Actuator type must be slide-actuated with raised level
• Termination style must be PC pin

Electrical Compatibility Criteria:

• Current rating must equal or exceed 150mA
• Voltage rating must equal or exceed 30VDC
• Operating temperature range must encompass -40°C to 85°C

Mechanical Compatibility Criteria:

• Height above board and overall length must be compatible with PCB layout constraints
• Contact material and finish must support the intended application environment

The substitute parts listed below satisfy these criteria with documented specifications from their respective manufacturers.

Parameter Comparison

Engineering Selection Recommendations

78B09T (Grayhill Inc.) - Primary Direct Substitute

The 78B09T is the direct successor to the 78B09 within the Grayhill 78 series. It maintains identical electrical ratings (150mA at 30VDC), mechanical configuration, and physical dimensions. The 78B09T is classified as active product status with ROHS3 compliance, addressing regulatory requirements that the obsolete 78B09 does not meet. This part is the preferred substitute for direct replacement in existing designs without modification.

206-9 (CTS Electrocomponents) - Conditional Substitute

The 206-9 maintains the same circuit configuration, 9-position count, and through-hole mounting with 0.100" pitch. However, the electrical ratings differ: 50mA at 24VDC versus the original 150mA at 30VDC. This part is suitable only for applications where the circuit operates at or below 50mA and 24VDC. The 206-9 offers extended operating temperature range (-55°C to 85°C) and superior electrical life (10,000 cycles). ROHS3 compliance is documented.

BD09 (C&K) - Conditional Substitute

The BD09 maintains the same circuit configuration, 9-position count, and through-hole mounting with 0.100" pitch. The electrical ratings are 100mA at 5VDC, which is below the original 150mA at 30VDC specification. This part is suitable only for low-voltage applications operating at 5VDC with current draw not exceeding 100mA. The BD09 features phosphor bronze contacts, washable design capability, and superior mechanical and electrical life (10,000 cycles each). ROHS3 compliance is documented.

Frequently Asked Questions (FAQ)

Q: Can the 78B09T be used as a direct replacement for the 78B09?

A: Yes. The 78B09T is the active product successor within the Grayhill 78 series. It maintains identical electrical ratings (150mA at 30VDC), mechanical configuration, pitch (0.100"), and physical dimensions (0.315" height, 0.980" length). The primary difference is product status (active versus obsolete) and RoHS3 compliance. No circuit modification is required.

Q: What are the limitations of using the 206-9 as a substitute?

A: The 206-9 has reduced electrical ratings: 50mA at 24VDC compared to the original 150mA at 30VDC. It is suitable only for applications where the circuit operates at or below 50mA and 24VDC. The height above board is also slightly greater (0.334" versus 0.315"), which may affect PCB layout in space-constrained designs. Verify that your application does not exceed these electrical limits before selection.

Q: What are the limitations of using the BD09 as a substitute?

A: The BD09 has significantly reduced electrical ratings: 100mA at 5VDC compared to the original 150mA at 30VDC. It is suitable only for low-voltage applications operating at 5VDC with current draw not exceeding 100mA. The height above board is lower (0.297" versus 0.315"), which may require PCB layout verification. Confirm that your application operates within these electrical constraints before selection.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. The 78B09T, 206-9, and BD09 are all documented as ROHS3 compliant. The original 78B09 is RoHS non-compliant. If regulatory compliance is a design requirement, any of the three substitute parts satisfy this criterion.

Q: Do the substitute parts have the same mechanical life as the original 78B09?

A: No. The 78B09 and 78B09T both specify 2,000 mechanical cycles. The 206-9 does not specify mechanical life. The BD09 specifies 10,000 mechanical cycles, which exceeds the original specification. For applications requiring extended mechanical life, the BD09 offers superior performance within its electrical rating constraints.

Q: Do the substitute parts have the same electrical life as the original 78B09?

A: No. The 78B09 and 78B09T both specify 2,000 electrical cycles. The 206-9 specifies 10,000 electrical cycles, and the BD09 specifies 10,000 electrical cycles. Both substitute parts offer extended electrical life compared to the original specification.

Q: What is the pitch specification, and do all parts match?

A: Pitch is the center-to-center distance between adjacent switch positions. All parts, including the main 78B09 and all substitutes, specify 0.100" (2.54mm) pitch. This ensures PCB footprint compatibility across all options.

Q: Are there packaging differences between the parts?

A: Yes. The 78B09 is supplied in bulk packaging. The 78B09T, 206-9, and BD09 are all supplied in tube packaging. Verify that your procurement and assembly processes accommodate tube packaging if selecting a substitute part.

Q: What contact materials are used in each part?

A: The 78B09 and 78B09T use copper alloy contacts with gold finish. The 206-9 contact material is not specified but includes gold finish. The BD09 uses phosphor bronze contacts with gold finish. All parts feature gold-plated contacts suitable for general-purpose switching applications.

Q: Can I use the 206-9 or BD09 in a 30VDC circuit?

A: No. The 206-9 is rated for 24VDC maximum, and the BD09 is rated for 5VDC maximum. Applying voltages exceeding these ratings will damage the parts and create safety hazards. Use only the 78B09T for 30VDC applications, or redesign the circuit to operate within the voltage constraints of alternative parts.