Square D 9999SP28R - Circuit Breaker | AmpState

Meet the Square D 9999SP28R, a molded case circuit breaker engineered for dependable branch circuit overcurrent and short-circuit protection in panelboards and load centers. Available from AmpState, this unit brings precise protection and seamless compatibility to residential, commercial, and light industrial electrical systems.

Compact, space‑saving protection with reliable performance

The 9999SP28R features a compact molded case design that maximizes panel space without compromising safety. Its thermal-magnetic trip unit delivers stable, repeatable protection by combining thermal sensing for overloads with magnetic tripping for immediate response to short circuits. This means fewer nuisance trips and more predictable operation when hard faults occur.

• Space-efficient design optimizes panel layout while maintaining full protection capabilities.
• Thermal-magnetic trip provides fast, reliable response to overloads and short circuits.
• OEM compatibility engineered to integrate with matching Square D load centers and panelboards for a seamless fit.
• Versatile applications suited for residential, commercial, and light industrial environments.

Technical details

• Manufacturer: Square D
• Part Number: 9999SP28R
• Type: Thermal-magnetic molded case circuit breaker
• Application: Branch circuit overcurrent and short-circuit protection

Use cases and practical benefits

Whether you’re upgrading an older panel, configuring a new installation, or refreshing a service entrance, the 9999SP28R delivers dependable protection with straightforward integration. Practical scenarios include:

• Upgrading panelboards in homes or multi‑unit buildings to improve protection and reliability
• Replacing aging breakers in light commercial panels to maintain code‑compliant safety margins
• Feeding critical branch circuits (lighting, outlets, small equipment) with proven protection against overcurrent and faults

Why this breaker stands out

This Square D molded case breaker is designed to align with the exact electrical characteristics of OEM panelboards, promoting cohesive protection schemes and minimizing compatibility concerns. The result is predictable trip behavior, cleaner panel coordination, and long‑term reliability across a variety of installations.

Upgrade your protection today with the Square D 9999SP28R and enjoy precise, balanced performance in a compact form factor—made to fit where space is at a premium and protection is non‑negotiable.