Main Breaker Panel Vs Main Lug

You can convert any panel to a subpanel by simply adding a ground bus and moving all the grounds to the added bus.

Main breaker panel vs main lug.

Main lug vs main breaker is simply a matter of whether the added panel has an integrated protection device. You need to remove that lug if converting to a subpanel. If you attach in your main box to a breaker then it can serve as the protection device for the sub but doesn t have to. Main lug load centers are sometimes referred to as add on.

There are situations where a back fed circuit breaker and a retainer clip required by nec are used to convert a main lug load center to a main breaker load center. Main lugs load centers are sometimes called sub or sub feed panels. A mcb panel is used when there is only a meter just outside and this feeder cable or conduit does not exceed 10 feet from meter to panel. For mlo panels the incoming cables are terminated on line side lugs that are attached directly to the bus no main overcurrent device exists in the panel.

If the panel was designed to be a main panel there would be a lug that connects the neutral ground bus to the panel. Main lug units are primarily used as a distribution panel where there is a main breaker upstream in the system. They are sometimes installed adjacent to a main panel to provide additional circuits when the main breaker panel is full or they may be installed far away from the main panel to provide a local disconnection for circuits in a detached building garage or room addition. You can feed it with less than 100 amps sent from my rct6203w46 using tapatalk.

If you attach to lugs in the main box then you need to have a main breaker in the sub panel. Main lug only panels are typically applied downstream of a main circuit breaker panel and are often referred to as secondary or add on panels. A main lug only mlo panel only has main lugs and is intended to be fed by a main breaker upstream. A main breaker panel mcb has a main breaker built into it.

Since you say a section is buried i assume garage is detached.