Circuit Breaker 2-Pole 50-Amp 120/240V Siemens Q21550CT Plug-On Ensure dependable electrical protection with the Siemens Q21550CT 2-Pole 50-Amp Circuit Breaker ? a high-performance plug-on mount breaker designed for safe, secure operation in Siemens Q-series load centers. Engineered with a thermal-magnetic trip mechanism, this breaker delivers fast, reliable response to overloads and short circuits, safeguarding wiring, appliances, and equipment in residential and light commercial electrical systems. Rated for 120/240 volts AC and 50 amps, this two-pole breaker is ideal for powering large 240V loads such as electric ranges, water heaters, air conditioning units, and subpanels. Its plug-on design allows for quick and secure installation directly onto the panel bus without the need for screws or additional hardware, ensuring a solid, low-resistance connection. The breaker is UL Listed and CSA Certified, meeting all applicable safety standards for residential electrical installations. Featuring a 10 kAIC (kiloAmpere Interrupting Capacity), the Q21550CT provides robust fault current protection, while its HACR rating confirms suitability for use with heating, air conditioning, and refrigeration equipment. The breaker is constructed with durable insulating materials and designed for indoor and outdoor use in properly enclosed panels. With a compact profile measuring 2 inches in width, 3 inches in height, and 3 inches in depth, it fits efficiently into standard panel layouts. The thermal-magnetic trip system ensures accurate, maintenance-free operation over time, responding to sustained overloads (thermal) and sudden short circuits (magnetic). The unit is designed for use in Siemens Q-series circuit breaker panels only. Note: Despite some conflicting data in source listings, the correct configuration for the Q21550CT is 2-pole, 50-amp, not 3-pole or 15/50 amp. This is consistent with Siemens' official naming convention and product specifications. Features - 2-pole, 50-amp circuit breaker for 120/240V AC systems - Plug-on mount design for fast, secure installation - Thermal-magnetic trip mechanism for overload and short-circuit protection - 10 kAIC interrupting capacity for safe fault handling - HACR rated for use with HVAC and refrigeration circuits - UL Listed and CSA Certified for code compliance - Suitable for indoor and outdoor electrical panels (when properly enclosed) - Compact size: 2" W x 3" H x 3" D - Designed for Siemens Q-series load centers only - Durable construction for long-term reliability Specifications - Brand Name: Siemens - Model Name: Siemens Q21550CT - Part Number: Q21550CT - UPC: 783643194984 - Product Type: Circuit Breaker - Number of Poles: 2 - Current Rating: 50 Amps - Voltage: 120/240 Volts AC - Circuit Breaker Type: Standard - Mounting Type: Plug-On - Trip Mechanism: Thermal-Magnetic - AIC Rating: 10,000 Amps (10 kAIC) - HACR Rated: Yes - UL Listed: Yes - CSA Certified: Yes - Wire Range: #6 to #14 AWG - Material: Plastic - Item Weight: 1.1 lbs - Product Dimensions: 3"D x 2"W x 3"H - Manufacturer: Siemens - Country of Origin: United States Product Application The Siemens Q21550CT 2-Pole 50-Amp Circuit Breaker is designed for use in Siemens Q-series load centers requiring reliable protection for 240-volt branch circuits. Ideal for residential applications such as electric ranges, dryers, well pumps, and central air conditioning systems, it ensures safe, long-term performance in both new installations and panel upgrades. Its plug-on design simplifies installation, while the robust thermal-magnetic trip system provides consistent protection. Trusted by electricians and contractors, this breaker delivers safety, durability, and compatibility within the Siemens Q-line ecosystem. Always verify panel compatibility before installation?this breaker is not interchangeable with other brands or series.