Hammond Manufacturing 631B Pulse Transformer Equivalent & Substitute Parts

Part Overview

The Hammond Manufacturing 631B is a 1mH SCR and Triac Trigger pulse transformer with a 1:1:1 turns ratio, designed for through-hole mounting applications. This component is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and component procurement.

Substiute Parts

631B

Hammond ManufacturingIn Stock: 1040631B Datasheet

Current PartRFQ

77202C

Murata Power Solutions Inc.In Stock: 121477202C Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 631B is determined by the following critical parameters:

• Transformer Type: SCR and Triac Trigger (Encapsulated)
• Inductance: 1mH
• Turns Ratio: 1:1:1
• Mounting Type: Through Hole
• Physical dimensions within acceptable tolerance for PCB layout
• RoHS3 compliance status

The Murata Power Solutions Inc. 77202C meets all substitution criteria, maintaining identical electrical specifications (1mH inductance, 1:1:1 turns ratio) and transformer classification. Physical dimensions are within acceptable variance for through-hole mounting applications. Both components carry ROHS3 compliance and EAR99 ECCN classification.

Parameter Comparison

Engineering Selection Recommendations

The Murata Power Solutions Inc. 77202C is the direct substitute for the obsolete Hammond Manufacturing 631B. Selection is based on:

• Identical electrical specifications (1mH inductance, 1:1:1 turns ratio)
• Matching transformer classification for SCR and Triac trigger applications
• Through-hole mounting compatibility
• Active product status ensuring ongoing availability
• Equivalent regulatory compliance (ROHS3, REACH Unaffected, EAR99)
• Physical dimensions within acceptable tolerance for standard PCB layouts

Frequently Asked Questions (FAQ)

Q: Can the Murata 77202C directly replace the Hammond 631B in existing designs?

A: Yes. Both components share identical inductance (1mH), turns ratio (1:1:1), transformer type classification, and mounting method. Physical dimensions are within acceptable variance for through-hole PCB applications.

Q: What is the significance of the obsolete status for the Hammond 631B?

A: Obsolete status indicates the Hammond 631B is no longer manufactured or supported by the original supplier. The Murata 77202C, with active product status, provides continued component availability for replacement and new procurement.

Q: Are there compliance differences between the two parts?

A: No. Both components carry identical regulatory classifications: ROHS3 Compliant, REACH Unaffected, and EAR99 ECCN designation.

Q: What are the physical dimension differences?

A: The Murata 77202C is marginally larger in length and width (0.016" and 0.012" respectively) but slightly shorter in seated height (0.028" lower). These differences are within standard PCB layout tolerances for through-hole components.

Q: Is the ET (Volt-Time) specification critical for substitution?

A: The Hammond 631B does not provide an ET specification in available documentation. The Murata 77202C specifies 120VµS. Verification against circuit requirements is necessary for applications where ET specification is a design constraint.