SIEMENS
SIEMENS Q240 40 A 2-Pole Plug-In Miniature Circuit Breaker 120/240V AC 48V DC
A 40 A two-pole plug-in breaker rated for 120/240 V AC and 48 V DC with a 10 kA interrupting capacity at 120 V AC
- TypeCircuit Breakers
- 40 A dual-pole protection for 120/240 V AC circuits
- 10 kA interrupting rating at 120 V AC for reliable fault clearing
- Plug-in mounting fits Siemens EQ load centres without tools
- Toggle actuator gives clear on/off status at a glance
- Accepts 8–4 AWG aluminium or 8–6 AWG copper conductors
40 A two-pole protection for EQ load centres
This Siemens Q240 miniature circuit breaker provides 40 A overcurrent protection on a 120/240 V AC system and is also rated for 48 V DC. It mounts by plug-in into compatible Siemens EQ load centres and uses a standard toggle actuator. The breaker carries a 10 kA interrupting rating at 120 V AC and fits a 125 A frame size. Builders who need a different amperage, a single-pole device or a bolt-on mounting style cannot use this model.
Plug-in mounting frees panel space
The plug-in mounting style allows the breaker to snap directly onto the bus bars of a Siemens EQ load centre without bolt-down hardware. Lug terminals accept copper conductors from 8 AWG to 6 AWG and aluminium conductors from 8 AWG to 4 AWG. Physical dimensions are 2.0 in long by 3.0 in wide by 3.0 in deep, so the unit occupies a standard two-pole slot. Installers who require a different terminal type or a larger frame size must select another product.
Standard toggle actuator and lug terminals only
The breaker ships with its integral toggle actuator and factory-fitted lug terminals; no separate handle, shunt trip or auxiliary contact is included. Software configuration is not applicable to this electromechanical device. Electricians who need field-installable accessories such as padlock attachments or remote operators must source them separately.
Highlights
- 40 A dual-pole protection for 120/240 V AC circuits
- 10 kA interrupting rating at 120 V AC for reliable fault clearing
- Plug-in mounting fits Siemens EQ load centres without tools
- Toggle actuator gives clear on/off status at a glance
- Accepts 8–4 AWG aluminium or 8–6 AWG copper conductors
Specifications
| Brand | Siemens |
|---|---|
| Type | Circuit Breakers |
Questions about this item
What is the 10 kA interrupting rating at 120 V AC for this breaker?
The breaker has a maximum AIR rating of 10 kA at 120 V AC, which is the limit that will trip first under sustained over-current conditions.
How much heat does the 40 A toggle breaker generate when running all day?
The unit measures 2.0 in long by 3.0 in wide by 3.0 in deep and mounts by plug-in, so heat dissipation depends on the load centre's ventilation and the 8 AWG to 4 AWG aluminium or 6 AWG copper conductors used.
Which Siemens load centre series must I already own for this Q-series breaker to fit?
It is compatible only with Siemens EQ load centres, requiring an available two-pole plug-in slot in a 125 A QP frame panelboard.
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