Blue Sea 7047 135A 187-Series Panel Mount Breaker

The Blue Sea Systems 7047 is a 135 amp panel mount breaker in the 187 Series, rated to 48 volts DC.

One hundred and thirty-five amps is an unusual figure, and it exists because cable ratings do not land on round numbers. A run sized at 135 amps needs a 135 amp breaker. Fitting the 150 leaves the cable unprotected through 15 amps of overload it was never rated for, and that overload is the one that heats a conductor slowly rather than clearing quickly.

Between the 120 and 150 amp units, this fills the gap for a large inverter or a heavy house bank feed where the conductor sizing says so. The thermal bi-metal element tolerates the brief inrush an inverter draws on startup rather than tripping on it.

Interrupt capacity is 5,000 amperes at 12 volts DC, 3,000 at 24 and 1,500 at 42, in Type III class with manual reset and trip free operation. The round self-trimming case installs with a hole saw, 5/16 studs take heavy gauge lugs, and it is waterproof and ignition protected to SAE J1171. Explore more marine circuit breakers.

• 135A, because cable ratings are not round numbers
• Fitting a 150 leaves 15 amps of overload unprotected
• Slow overload is what heats a conductor
• Between the 120 and 150 amp units