Overview
The Siemens D150 50A circuit breaker is a UL-listed QO replacement breaker engineered for use in Square D QO brand load centers. This single pole breaker provides 50-ampere protection at 120/240V, 60Hz and features a plug-in design that snaps onto QO-type bussing. Available in bulk boxes of 16 units, the D150 is ideal for electrical contractors and maintenance professionals requiring dependable breaker inventory for panel repairs, expansions, and replacements.
Key Features
- QO Compatibility: UL listed for Square D QO brand load centers; drop-in replacement design
- Voltage Rating: 120/240V AC, 50-ampere single pole configuration
- Plug-In Design: Snaps directly onto QO-type bussing for quick installation
- 3/4-Inch Frame: Compact form factor fits standard breaker mounting slots
- Bulk Availability: Sold in box of 16 for efficient fleet management and spares inventory
Technical Specifications
- Amperage Rating: 50A
- Voltage: 120/240V AC
- Frequency: 60Hz
- Poles: 1 (Single Pole)
- Type/Style: QO Replacement
- Frame Size: 3/4-Inch
- Connection Type: Plug-In (Snap-On QO Bussing)
- Certifications: UL Listed
- Item Weight: 4 ounces per breaker
- Package Dimensions: 3 x 2.9 x 0.7 inches
- Warranty: 1 Year Limited Manufacturer Warranty
Typical Applications
The D150 is commonly used in:
- Residential and light commercial electrical panels with Square D QO load centers
- Circuit protection for branch circuits requiring 50-ampere overcurrent protection
- Panel maintenance and emergency replacement inventory in service vehicles
- New circuit installations where expansion of existing QO-compatible panels is required
- Industrial control panels and machinery circuits rated for 120/240V operation
Compatibility & Replacements
The Siemens D150 is a direct replacement for Square D QO150 single pole 50-ampere breakers. It is not compatible with Siemens QP, QT, or other proprietary Siemens panel types—only Square D QO brand load centers accept the D150. When installing, verify your load center accepts QO-type breakers. Siemens recommends using only new breakers and advises against installation of used units, as doing so may void panel warranty.
