Eaton / Cutler-Hammer GHB3040 Molded Case Circuit Breaker

This G-frame bolt-on breaker installs directly into Eaton Pow-R-Line panelboards, specifically 480V models like the PRL2a. It is also compatible with Series C panelboards, as well as select switchboards and motor control centers designed for bolt-on branch devices.

No. This breaker has a slash voltage rating of 480Y/277 Vac. Per the National Electrical Code, slash-rated breakers are only permitted on solidly grounded wye systems where the nominal voltage to ground does not exceed the lower number (277V). It is not safely rated for ungrounded or corner-grounded delta systems.

The standard factory-installed aluminum pressure lugs accept bare copper or aluminum wire ranging from 10 AWG up to 1/0 AWG. Always verify the terminal torque requirements printed on the breaker label before terminating conductors.

Yes. Eaton acquired both the Cutler-Hammer and Westinghouse distribution equipment lines. A modern Eaton GHB3040 is the direct physical and electrical replacement for legacy breakers sharing the same catalog number.

Yes. The thermal-magnetic trip unit is calibrated for a standard 40 degree C (104 degree F) ambient environment. Operating the breaker in an environment hotter than 40 degrees C will cause the thermal element to trip at a lower current, requiring you to apply a derating factor to your circuit design.

Yes, the GHB3040 is rated for up to 125/250 Vdc with a 14 kA interrupting capacity. When using it in DC applications, consult Eaton engineering guidelines to determine if multiple poles must be wired in series to safely clear a DC fault.

No. This breaker features a fixed thermal and fixed magnetic trip unit. Neither the long-time overload protection nor the instantaneous short-circuit pickup levels can be adjusted in the field.

Yes. GHB breakers are frequently utilized as downstream branch devices in series-rated combinations with upstream main breakers to achieve a higher overall short-circuit current rating. Always verify that the specific main and branch combination is UL listed in the Eaton series rating charts before installation.