NH0G125 Equivalent & Substitute Parts Reference

Part Overview

The NH0G125 is a 125A square fuse rated for 500 VAC and 440 VDC operation, manufactured by Littelfuse Inc. and classified as NH type with fast-blow response characteristics. This component is designated as obsolete, making identification of compatible substitute parts essential for ongoing system maintenance and component procurement. The fuse is designed for motor protection applications and requires a dedicated holder for installation.

Substiute Parts

NH0G125

Littelfuse Inc.In Stock: 894NH0G125 Datasheet

Current PartRFQ

125NHG00B

Eaton - Bussmann Electrical DivisionIn Stock: 990125NHG00B Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the NH0G125 is determined by the following critical parameters:

• Current Rating: Must be 125A to maintain circuit protection design specifications
• Fuse Class: Must be NH type to ensure mechanical and electrical compatibility with existing holder assemblies
• Voltage Rating - AC: Must be 500 VAC minimum to support the primary operating voltage
• Response Time: Must be Fast Blow to match the original protection characteristics
• Package / Case: Must be Rectangular, Blade configuration for physical compatibility with NH-type holders
• Mounting Type: Must require holder-based installation

The substitute part 125NHG00B meets these critical parameters. The DC voltage rating difference (250 VDC vs. 440 VDC) represents a reduction in maximum DC capability; however, this part remains functionally equivalent for applications where the DC voltage requirement does not exceed 250 VDC.

Parameter Comparison

Engineering Selection Recommendations

The 125NHG00B is the direct substitute for the obsolete NH0G125. Both parts share identical current ratings, AC voltage specifications, response characteristics, and NH class designation. The substitute part is manufactured by Eaton - Bussmann Electrical Division and maintains active product status, ensuring ongoing availability and supply chain continuity.

The primary technical difference is the DC voltage rating: the substitute part is rated for 250 VDC maximum, compared to the original 440 VDC rating. Selection of the 125NHG00B is appropriate for applications where the system DC voltage does not exceed 250 VDC. For applications requiring the full 440 VDC DC capability, alternative parts meeting this specification must be evaluated.

The 125NHG00B provides enhanced compliance status, meeting ROHS3 requirements compared to the non-compliant original part. Both parts carry VDE approval; the substitute additionally holds CE certification.

Frequently Asked Questions (FAQ)

Q: Can the 125NHG00B directly replace the NH0G125 in all applications?

A: The 125NHG00B is mechanically and electrically compatible for AC applications at 500 VAC and DC applications not exceeding 250 VDC. If your system operates at DC voltages above 250 VDC, the substitute part is not suitable.

Q: Are the physical dimensions compatible between these parts?

A: Both parts use Rectangular, Blade package configuration and are designed for NH-type holders. Physical dimensions differ slightly; verify that the substitute part dimensions (54.00mm x 30.00mm x 50.00mm) are compatible with your existing holder assembly.

Q: What is the significance of the product status change from Obsolete to Active?

A: The Active status of the 125NHG00B ensures continued manufacturing and availability, eliminating supply chain risk associated with the obsolete NH0G125.

Q: Does the RoHS compliance difference affect substitution?

A: The 125NHG00B meets ROHS3 compliance standards, while the original part does not. This represents an improvement in environmental and regulatory compliance for new installations or system upgrades.

Q: Are there breaking capacity differences between these parts?

A: The original part specifies 120kA AC and 25kA DC breaking capacity. The substitute part specifies 120kA breaking capacity. Verify that the 120kA specification meets your system's short-circuit protection requirements.