Square D | SDT120 | Circuit Breaker | 20A | 1-Pole | 240V | Plug-In

Meet the Square D SDT120 20A 1-Pole 240V Plug-In Circuit Breaker—a direct-fit device designed for reliable protection and hassle-free maintenance in compatible Square D panels. Engineered for retrofit, replacement, and routine service tasks, this breaker helps you restore circuit safety with minimal downtime.

Key specs at a glance

• Amperage: 20A
• Poles: 1-Pole
• Voltage: 240V
• Mounting: Plug-In
• Series/Type: SDT (Square D SDT family)
• Part reference: SDT120

Why this SDT120 stands out

This is not just a generic breaker. It’s a purpose-built replacement for panels that accept Type SDT plug-in breakers. The SDT120 delivers precise 20‑amp protection for a dedicated 240V circuit, helping prevent overloads and reduce the risk of electrical fires. The plug-in design means faster installation or replacement—pull the old unit, snap in the new one, and you’re back in service in minutes (with power off and following safety guidelines).

Who benefits most?

• Homeowners performing DIY panel maintenance on Square D systems that specify SDT breakers.
• Technicians conducting retrofit work or replacements in commercial or residential panels requiring 1‑pole, 240V protection.
• Anyone seeking a straightforward, spec-matched replacement when a circuit trips or a part fails.

Important compatibility notes

Before ordering, confirm that your panel accepts SDT-type, plug-in breakers and that the 20A rating aligns with the circuit you intend to protect. The part number SDT120 is the best reference for compatibility, so verify against your panel’s labeling and service manual.

Practical tips and safe installation

• Always shut off main power and verify the circuit is de-energized before replacement.
• Handle breakers by the body; avoid touching the live terminals to reduce the risk of shock.
• Store spare SDT-style breakers in their original packaging to preserve terminals and prevent damage.
• Keep a small stock of common ratings (15A, 20A, 30A) in your service kit for quick swaps where permitted by code and panel design.

Engineered for reliability in 240V systems, the SDT120 Plug-In Circuit Breaker is an effective, industry-standard solution for dependable electrical protection. When you need a precise, part-number-directed replacement that you can install quickly, this 20A, 1-Pole SDT breaker fits the bill.