Square D EGB34040 Miniature Circuit Breaker

No. The EGB34040 is an E-frame bolt-on breaker specifically designed for Square D NF panelboards. NQ panelboards require QO or QOB series breakers, and I-Line panelboards require I-Line molded case circuit breakers.

The middle letter designates the maximum interrupting capacity at 480Y/277VAC. The EDB series is rated for 18kA, the EGB provides 35kA, and the EJB offers 65kA. Because they share the same physical footprint, you can upgrade to an EGB or EJB if your system requires a higher fault current rating.

Yes. The EGB34040 is UL Listed as HACR type, making it approved for heating, air conditioning, and refrigeration equipment. It is also HID rated for use with high-intensity discharge lighting circuits.

The factory aluminum lugs should be torqued to 34.5 lbf-in for 14 AWG to 10 AWG wire, and 49.6 lbf-in for 8 AWG to 2/0 AWG wire. Always verify exact specifications on the physical breaker label before terminating.

This 3-pole E-frame breaker requires three standard circuit spaces when mounted in a Square D NF panelboard.

Yes. The EGB34040 features the exact same dimensions and bolt-on mounting configuration as the EDB34040. Replacing an EDB with an EGB simply upgrades the interrupting capacity from 18kA to 35kA at 480Y/277VAC.

Yes, Schneider Electric permits E-frame breakers on 400 Hz systems, though they require derating and are not UL Listed for this specific application. The thermal derating multiplier is 0.97, the magnetic multiplier is 2.6, and the interrupting rating is reduced to 10 percent of the standard 60 Hz rating.

The "LI" designation indicates standard thermal-magnetic protection. The Long-time (L) thermal element reacts to sustained overloads by heating up and tripping the breaker, while the Instantaneous (I) magnetic element responds immediately to severe short circuits. Both trip settings are fixed at the factory.