HD4812 Solid State Relay SPST-NO Equivalent & Substitute Parts

Part Overview

The HD4812 is an active Sensata-Crydom solid state relay (SSR) with SPST-NO (1 Form A) configuration, rated for 12A load current across 48V to 530V AC output range. This chassis-mount hockey puck relay operates with 3–32VDC input control voltage and features zero-cross switching for AC loads. The part is RoHS compliant and actively manufactured. Substitute parts become necessary when inventory constraints, regional availability, or specific compliance requirements necessitate alternative sourcing while maintaining functional equivalence within defined electrical and mechanical parameters.

Substiute Parts

HD4812

Sensata-CrydomIn Stock: 1070HD4812 Datasheet

Current PartRFQ

84134100

Sensata TechnologiesIn Stock: 106384134100 Datasheet

MFR RecommendedRFQ

84137000N

CrouzetIn Stock: 89184137000N Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the HD4812 is determined by the following critical parameters:

• Circuit Configuration: Must be SPST-NO (1 Form A) to maintain identical switching topology
• Output Type: Must be AC with zero-cross switching to preserve load control characteristics
• Mounting Type: Must be chassis mount to ensure mechanical compatibility
• Package / Case: Must be hockey puck form factor for physical interchangeability
• Termination Style: Must be screw terminal for connection compatibility
• Input Voltage Range: Must encompass or overlap the 3–32VDC control voltage specification
• Load Voltage Range: Must support the 48V–530V operating window or a subset thereof
• Load Current: Must be rated at or above 12A to handle the specified load
• RoHS Compliance: Must meet or exceed the RoHS standard for regulatory alignment

The two substitute parts listed—84134100 (Sensata Technologies) and 84137000N (Crouzet)—satisfy the core functional and mechanical requirements. However, each exhibits distinct electrical parameter boundaries that define their application scope relative to the HD4812.

Parameter Comparison

Engineering Selection Recommendations

84134100 (Sensata Technologies) is suitable for applications requiring load voltage operation up to 660V. This part extends the upper voltage boundary beyond the HD4812 specification. The load current rating of 10A is lower than the HD4812's 12A rating; therefore, this substitute is appropriate only when the actual load current does not exceed 10A. The input voltage range (4–32VDC) is compatible with the HD4812 control circuit. ROHS3 compliance exceeds the RoHS requirement. This part is actively manufactured and available in bulk packaging.

84137000N (Crouzet) operates within a restricted load voltage window of 24V–280V, which is a subset of the HD4812's 48V–530V range. This substitute is applicable only to applications where the load voltage remains within the 24V–280V boundary. The 10A load current rating applies the same constraint as the 84134100. The input voltage range (4–32VDC) is compatible. RoHS compliance is met. This part is actively manufactured and supplied in box packaging.

Both substitutes maintain identical circuit topology, output switching characteristics, and mechanical form factor. Selection between them depends on the specific load voltage and current requirements of the target application. Neither substitute provides a direct one-to-one replacement across the full HD4812 electrical specification range.

Frequently Asked Questions (FAQ)

Q: Can the 84134100 replace the HD4812 in all applications?

A: The 84134100 is functionally equivalent for applications where the load current does not exceed 10A and the load voltage remains within the 48V–660V range. If the application requires the full 12A load current capacity of the HD4812, the 84134100 is not suitable.

Q: What is the primary limitation of the 84137000N as a substitute?

A: The 84137000N operates only within a 24V–280V load voltage range. It cannot be used in applications requiring load voltages above 280V or below 24V. The HD4812 supports 48V–530V, so the 84137000N is restricted to a narrower voltage window.

Q: Are the input voltage ranges of the substitutes compatible with the HD4812 control circuit?

A: Yes. Both substitutes accept 4–32VDC input control voltage, which overlaps with the HD4812's 3–32VDC specification. The 1VDC lower threshold on the substitutes does not affect compatibility with standard 3–32VDC control circuits.

Q: Do the substitutes maintain the same physical form factor?

A: Yes. All three parts—HD4812, 84134100, and 84137000N—are hockey puck chassis-mount relays with screw terminal connections. They are mechanically interchangeable in terms of mounting and connection interface.

Q: What is the difference between RoHS and ROHS3 compliance?

A: ROHS3 represents a more recent iteration of the RoHS directive with updated substance restrictions. ROHS3 compliance exceeds the RoHS requirement and indicates adherence to current regulatory standards. Both compliance levels are acceptable for applications requiring RoHS certification.

Q: Can I use the 84134100 for a 12A load if the voltage is within range?

A: No. The 84134100 is rated for a maximum of 10A load current. Using it at 12A exceeds its electrical rating and voids the manufacturer's specifications.

Q: Which substitute should I select for a 48V–280V application with 10A load current?

A: Both the 84134100 and 84137000N are suitable for this application. The 84134100 provides extended voltage capability (up to 660V) if future requirements change, while the 84137000N is optimized for the lower voltage range. Either part meets the stated electrical requirements.