NH00CM63 Square Fuse 63A 500VAC/440VDC Equivalent & Substitute Parts

Part Overview

The NH00CM63 is a square fuse rated for 63A at 500VAC/440VDC, manufactured by Littelfuse Inc. This component is classified as obsolete, requiring identification of active equivalent parts for continued system support. The fuse features fast-blow response characteristics with indicating capability, designed for motor protection applications in industrial environments. Due to its obsolete status, sourcing active alternatives is necessary for maintenance and new installations.

Substiute Parts

NH00CM63

Littelfuse Inc.In Stock: 1205NH00CM63 Datasheet

Current PartRFQ

63NHG000B

Eaton - Bussmann Electrical DivisionIn Stock: 84263NHG000B Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

The 63NHG000B from Eaton - Bussmann Electrical Division qualifies as a direct substitute based on the following critical parameters:

• Current Rating Match: Both parts are rated at 63A
• AC Voltage Match: Both maintain 500VAC rating
• Fuse Class Match: Both are NH class fuses
• Response Characteristic Match: Both feature fast-blow response
• Mounting Compatibility: Both require holder mounting with rectangular blade package configuration
• Approval Agency: Both carry VDE certification

The primary electrical difference is the DC voltage rating: NH00CM63 supports 440VDC while 63NHG000B supports 250VDC. This represents a reduced DC capability in the substitute part. The 63NHG000B is currently active in production, whereas the NH00CM63 is obsolete.

Parameter Comparison

Engineering Selection Recommendations

The 63NHG000B is the qualified substitute for NH00CM63 based on product status and compliance considerations:

• Active Production Status: The 63NHG000B is actively manufactured by Eaton - Bussmann, ensuring long-term availability and supply chain continuity compared to the obsolete NH00CM63.

• RoHS Compliance: The 63NHG000B meets RoHS compliance requirements, whereas the NH00CM63 is non-compliant. This distinction is significant for applications subject to environmental regulations.

• Electrical Compatibility: Both parts maintain identical AC voltage ratings (500VAC) and current ratings (63A) with matching NH class specifications and fast-blow characteristics.

• DC Voltage Consideration: Applications operating exclusively at or below 250VDC can directly substitute the 63NHG000B. Systems requiring the full 440VDC DC rating of the original part require evaluation of actual operating conditions to determine if the reduced 250VDC rating is acceptable.

• Certification Alignment: Both parts carry VDE approval, maintaining regulatory compliance in applications requiring this certification.

Frequently Asked Questions (FAQ)

Q: Can the 63NHG000B directly replace NH00CM63 in all applications?

A: Direct substitution is valid for applications operating at 500VAC and DC voltages not exceeding 250VDC. If the system operates at DC voltages above 250VDC, the reduced DC rating of the 63NHG000B must be evaluated against actual circuit requirements.

Q: What is the significance of the different physical dimensions between these parts?

A: Both parts use rectangular blade packages compatible with standard NH fuse holders. The dimensional differences (NH00CM63: 2.126" L x 2.020" W x 0.787" H; 63NHG000B: 2.126" L x 0.827" W x 1.693" H) reflect different internal construction but maintain mechanical compatibility with NH-class holder systems.

Q: Why is RoHS compliance important for this substitution?

A: RoHS compliance indicates the part meets environmental and material restrictions applicable in many jurisdictions and industries. The 63NHG000B's RoHS compliance provides regulatory advantage over the non-compliant NH00CM63 for new installations and systems subject to environmental standards.

Q: Are there any breaking capacity differences between these parts?

A: The NH00CM63 specifies 120kA AC and 25kA DC breaking capacity. The 63NHG000B specifies 120kA breaking capacity. Both maintain adequate breaking capacity for NH class applications at their respective voltage ratings.

Q: What holder compatibility should be verified?

A: Both parts require NH-class fuse holders with rectangular blade configuration. Verify that existing holder systems are rated for NH class and compatible with the blade dimensions of the substitute part before installation.