Siemens Q345H Circuit Breaker – QPH Series – 45A – 3 Pole – 240VAC – Plug-On – Thermal Magnetic – 22kAIC

The Siemens Q345H is a QPH Series miniature molded case circuit breaker designed for residential, commercial, and light industrial electrical distribution applications. Rated at 45A and 240VAC, this 3-pole breaker provides reliable thermal-magnetic protection against overloads and short circuits while offering a high interrupting capacity of 22kA at 240VAC for installations with elevated fault current requirements.

Its plug-on design allows quick installation into compatible Siemens EQ, PL, ES, and Ultimate load centers. The Q345H also serves as a direct replacement for legacy Murray MP345 circuit breakers, making it an ideal upgrade solution for existing electrical systems. Featuring a common-trip mechanism and HACR certification, it is well-suited for protecting HVAC equipment, motors, and three-phase distribution circuits.

Specifications

• Brand: Siemens
• Part Number: Q345H
• Series: QPH Series
• Category: Miniature Molded Case Circuit Breaker
• Mounting Type: Plug-On
• Configuration: 3 Pole
• Phase: 3 Phase
• Protection Type: Thermal Magnetic
• Trip Function Code: LI
• Trip Functions: Long-Time, Instantaneous
• Trip Adjustability: Fixed
• Standards: UL 489, CSA C22.2 No. 5

Electrical Ratings

• Current Rating: 45A
• Voltage Rating: 240VAC
• Interrupting Capacity: 22kA @ 240VAC
• Frequency: 50/60 Hz
• Temperature Rating: 40°C

Construction

• Plug-on mounting design
• Thermal-magnetic trip mechanism
• High interrupting capacity construction
• Common-trip operation across all poles
• Lug terminal connections
• HACR-rated design
• Optional padlock attachment compatibility

Conductor Compatibility

• Copper Wire Range: 8–6 AWG
• Aluminum Wire Range: 8–4 AWG
• Minimum Wire Size: 8 AWG
• Maximum Wire Size: 4 AWG

Functions

• Overload protection
• Short-circuit protection
• Long-time delay protection
• Instantaneous fault protection
• Simultaneous three-pole tripping

Applications

• Siemens EQ Load Centers
• Siemens PL Load Centers
• Siemens ES Load Centers
• Siemens Ultimate Load Centers
• Commercial electrical distribution
• HVAC equipment protection
• Three-phase motor circuits
• Industrial control systems
• Murray MP345 replacement applications

Certifications & Approvals

• UL Listed
• CSA Certified
• HACR Rated

Returns are easy

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

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