V251HC40 Equivalent & Substitute Parts

Part Overview

The V251HC40 is a 390 V, 40 kA Transient Voltage Suppressor (TVS) varistor manufactured by Littelfuse Inc. in a bolt-mount disc configuration (40mm). This component is designed for transient voltage protection in industrial and power distribution applications. The part is currently Active in product status with full RoHS3 compliance and REACH unaffected designation. Substitute parts are identified when electrical parameters, mechanical form factor, and compliance certifications remain identical across alternative series designations.

Substiute Parts

V251HC40

Littelfuse Inc.In Stock: 1111V251HC40 Datasheet

Current PartRFQ

V251HA40

Littelfuse Inc.In Stock: 1064V251HA40 Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

The V251HA40 qualifies as a parametric equivalent to the V251HC40 based on the following substitution criteria:

• Identical varistor voltage rating: 390 V (typical), with matching minimum (351 V) and maximum (429 V) tolerances
• Identical surge current capacity: 40 kA
• Identical maximum AC and DC voltage specifications: 250 V AC / 330 V DC
• Identical energy absorption: 370 J
• Identical mechanical form factor: Bolt mount, disc 40mm with formed tabs
• Identical electrical characteristics: 1 circuit, 5000 pF capacitance @ 1 MHz
• Identical operating temperature range: -55°C to 85°C
• Identical compliance status: RoHS3 compliant, REACH unaffected, MSL 1

The substitution is based solely on matching electrical performance and mechanical compatibility. The difference between HC and HA series designations does not affect functional equivalence for this application.

Parameter Comparison

Engineering Selection Recommendations

Both the V251HC40 and V251HA40 are Active products with identical electrical specifications and mechanical configurations. Selection between these parts should be based on availability and supply chain considerations. Both parts maintain full RoHS3 compliance and REACH unaffected status, making them suitable for applications requiring environmental regulatory adherence. The interchangeability is complete at the functional level, with no performance differentiation between the HC and HA series designations for this voltage and current rating.

Frequently Asked Questions (FAQ)

Q: Can V251HA40 be used as a direct replacement for V251HC40? A: Yes. The V251HA40 is a parametric equivalent with identical electrical ratings (390 V, 40 kA), energy absorption (370 J), and mechanical form factor (bolt mount, 40mm disc). All electrical and physical specifications match exactly.

Q: What is the difference between the HC and HA series designations? A: The series designation does not affect electrical performance or mechanical compatibility for this part number. Both series meet identical specifications for varistor voltage, surge current, and physical dimensions.

Q: Are there any compliance or certification differences? A: No. Both parts carry identical RoHS3 compliance, REACH unaffected status, and MSL 1 moisture sensitivity level. Regulatory and environmental certifications are equivalent.

Q: Can these parts be used interchangeably in existing designs? A: Yes. The identical bolt-mount configuration, 40mm disc form factor, and formed tab connections ensure mechanical and electrical interchangeability without design modification.

Q: What applications require 390 V, 40 kA varistors? A: These components are used in transient voltage suppression circuits for industrial power distribution, motor control, and high-energy surge protection applications where 250 V AC / 330 V DC maximum operating voltages are specified.

Q: Is inventory availability a factor in part selection? A: Yes. The V251HC40 has 1036 pcs in stock, while the V251HA40 has 1023 pcs available. Both maintain adequate inventory for production requirements.