ZINSCO QB24-1040 N 40A 1P 120V Single-pole Molded Case Circuit Breaker QB241040

Description:

The Zinsco QB24-1040 N is a 40 Amp, single-pole molded case circuit breaker designed for use in Zinsco / GTE Sylvania panelboards. It operates on 120V systems and features a thermal-magnetic trip mechanism to protect circuits from overloads and short circuits. This breaker belongs to the QB24 series and uses a bolt-on mounting design, ensuring a secure connection to the panel bus in legacy electrical systems.

Applications:

This breaker is commonly used in residential and light commercial electrical systems for branch circuits requiring 40A protection, such as electric heaters, compressors, dedicated appliance circuits, and small equipment loads. It is specifically intended for installation in Zinsco bolt-on panels typically found in older electrical installations.

Technical Specifications:

• Manufacturer: Zinsco / GTE Sylvania
• Model / Part Number: QB24-1040 N
• Product Type: Molded Case Circuit Breaker (Bolt-On)
• Poles: 1-Pole
• Current Rating: 40 Amps
• Voltage Rating: 120 VAC
• Mounting: Bolt-on (QB series)
• Trip Type: Thermal-magnetic
• Interrupt Rating: ~10 kAIC (typical class)
• Function: Overcurrent and short circuit protection
• Status: Obsolete / discontinued (surplus availability)

Common Replacements:

• Square D QO140 1-Pole 40A Circuit Breaker
• Siemens Q140 1-Pole 40A Circuit Breaker
• Connecticut Electric UBIZ40 1-Pole 40A Zinsco Replacement Breaker