Square D FC34035 Molded Case Circuit Breaker

This breaker is designed exclusively for Square D I-Line panelboards and switchboards. It features a plug-on phase connection that mounts directly to the I-Line bus assembly.

The FC frame is a legacy F-frame breaker and is no longer manufactured. The modern replacement for I-Line panels is the PowerPact H-frame series, specifically the HJA36035, which provides the same 35A rating and I-Line mounting.

The breaker uses a plug-on design for the line side, which attaches directly to the panelboard bus. The load side features standard mechanical lugs for wire termination.

No. I-Line breakers like the FC34035 feature integrated mounting brackets and plug-on jaws, allowing them to attach directly to the panelboard bus without additional hardware kits.

Square D I-Line breakers utilize a blow-on jaw design. During high-fault short-circuit conditions, magnetic forces push the jaws tighter against the busbar, maintaining a secure connection when it is needed most.

Yes. Thermal-magnetic I-Line breakers like the FC34035 do not have Line and Load markings, meaning they can be reverse fed. This is commonly done when using the breaker as a back-fed main in an I-Line panelboard.

LI stands for Long-Time and Instantaneous protection. The Long-Time function protects against sustained overloads, while the Instantaneous function provides immediate tripping during severe short circuits. Both settings are fixed on the thermal-magnetic FC34035.

No. The FC34035 is an I-Line breaker and will not fit in NQ or NF panelboards. Those panels require QO, EDB, or similar branch breakers depending on the specific panel type.