Siemens ND63T120 Trip Unit – Sentron Series – 1200A – 3 Pole – 600VAC – Thermal Magnetic – ND/HND Compatible

The Siemens ND63T120 is a Sentron Series molded case circuit breaker trip unit designed for use with Siemens ND and HND frame breakers. Rated at 1200A and 600VAC, this 3-pole thermal-magnetic trip unit provides reliable overload and short-circuit protection for high-capacity industrial and commercial power distribution systems.

This trip unit features Long-Time and Instantaneous (LI) protection functions, ensuring dependable response to sustained overload conditions and high-level fault currents. It is engineered for integration into compatible ND and HND frame breaker assemblies, delivering consistent protection and coordination in demanding electrical environments.

Built for heavy-duty applications, the ND63T120 is UL listed and designed for main and feeder breaker configurations where high interrupting performance and reliable trip coordination are essential.

Specifications

• Brand: Siemens
• Part Number: ND63T120
• Series: Sentron Series
• Type: Trip Unit / Programmer
• Frame Compatibility: ND / HND Frame
• Category: Molded Case Circuit Breaker Trip Unit
• Configuration: 3 Pole
• Protection Type: Thermal Magnetic
• Trip Functions: LI – Long-Time and Instantaneous

Electrical Ratings

• Current Rating: 1200A
• Voltage Rating: 600VAC
• Interrupting Capacity: 50kA @ 480VAC
• Interrupting Capacity: 25kA @ 600VAC

Construction

• Heavy-duty industrial trip unit design
• Compatible with ND and HND frame circuit breakers
• Precision thermal-magnetic sensing system
• Plug-in style integration (frame dependent)
• Rugged construction for high-load applications

Functions

• Overload protection
• Short-circuit protection
• Long-time delay protection
• Instantaneous fault protection
• Coordinated breaker tripping performance

Dimensions

• Width: 9 in
• Height: 16 in
• Depth: 6 in

Standards

• UL Listed
• CSA Approved

Applications

• Industrial power distribution systems
• Commercial switchboards and main panels
• Heavy-duty feeder and main breaker protection

Returns are easy

You may return items within 30 days of delivery for a refund.

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