Equivalent & Substitute Parts for 1250-2S-400

Part Overview

The Bourns 1250-2S-400 is an active Transient Voltage Suppressor (TVS) module designed for AC circuit protection applications. This Type 2/Type 4 device provides surge suppression with remote signaling contacts and thermal protection, rated for 277VAC continuous operation. The product is actively manufactured and stocked, with full compliance to RoHS3 and international safety standards. Substitute parts are identified to support procurement flexibility, inventory management, and application-specific requirements where equivalent electrical and mechanical parameters are maintained.

Substiute Parts

1250-2S-400

Bourns Inc.In Stock: 11921250-2S-400 Datasheet

Current PartRFQ

SPD2-350-2P0-R

LittelfuseIn Stock: 795SPD2-350-2P0-R Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 1250-2S-400 is determined by the following critical parameters:

Electrical Compatibility Criteria:

• Number of Poles: Must equal 2
• Current - Discharge (Nom) (8/20µS): Must equal 20 kA
• Current - Discharge (Max) (8/20µS): Must equal 50 kA
• Voltage - Protection Level (VP) (2416): Must be within acceptable range (1.75 kV - 1.8 kV)
• Features: Must include Remote Signaling Contacts and Thermal Protection

Mechanical Compatibility Criteria:

• Mounting Type: Must be DIN Rail
• Form: Module-based construction acceptable

Regulatory Compliance Criteria:

• RoHS3 Compliant status required
• Active product status required

The substitute part SPD2-350-2P0-R (Littelfuse) meets these core substitution parameters while maintaining functional equivalence for circuit protection applications.

Parameter Comparison

Engineering Selection Recommendations

Both the 1250-2S-400 and SPD2-350-2P0-R are active products with full RoHS3 compliance and thermal protection features. Selection between these parts is based on application voltage requirements and regulatory jurisdiction:

The 1250-2S-400 is suitable for applications requiring 420VAC continuous operating voltage with CE, CSA, and UR certifications. The SPD2-350-2P0-R is suitable for applications with 350VAC maximum continuous operating voltage and requiring cURus, UL, or VDE certifications. Both devices maintain equivalent discharge current ratings (20 kA nominal, 50 kA maximum) and protection levels within 1.75 kV - 1.8 kV range. The SPD2-350-2P0-R provides higher short circuit rating (200 kA) compared to the 1250-2S-400 (100 kA). Operating temperature ranges differ by 10°C at the lower bound and 5°C at the upper bound.

Frequently Asked Questions (FAQ)

Q: Can the SPD2-350-2P0-R replace the 1250-2S-400 in all applications?

A: Substitution is valid only when the application voltage does not exceed 350VAC continuous operation. The 1250-2S-400 supports higher continuous operating voltage (420VAC). Verify application voltage requirements before substitution.

Q: What is the significance of the different Type ratings (Type 2/Type 4 vs. Type 1/Type 2)?

A: Type ratings indicate surge protection categories per IEC standards. The 1250-2S-400 covers Type 2 and Type 4 protection, while the SPD2-350-2P0-R covers Type 1 and Type 2. Application requirements determine which Type rating is necessary.

Q: Are the approval agencies interchangeable between these parts?

A: No. The 1250-2S-400 carries CE, CSA, and UR approvals. The SPD2-350-2P0-R carries cURus, UL, and VDE approvals. Select the part matching your regional regulatory requirements.

Q: What is the impact of the 100 kA vs. 200 kA short circuit rating difference?

A: The SPD2-350-2P0-R has a higher short circuit rating, providing greater protection margin in high-fault-current environments. The 1250-2S-400 is rated for 100 kA short circuit current. Application fault current levels determine which rating is appropriate.

Q: Are both parts DIN Rail mountable?

A: Yes. Both the 1250-2S-400 and SPD2-350-2P0-R use DIN Rail mounting. The 1250-2S-400 requires a Base + Module configuration, while the SPD2-350-2P0-R is Module Only. Verify mounting infrastructure compatibility.

Q: Do both parts include remote signaling contacts?

A: Yes. Both devices include remote signaling contacts and thermal protection features, enabling status monitoring and fault indication in circuit protection systems.