Main Lug or Main Breaker

[kmacht]

I'm a little confused and need some advice. I posted a while back about running a sub panel to my detached garage. I am all set as far as wires, ground, etc but am still a little confused on what panel I actually need. The feed for the sub panel will be hooked to a 60 amp breaker in my house and run through conduit for about 50' to my garage. My question is, do I need a main breaker panel or a main lug panel in the garage. I thought it would only need a main lug since the feed wire is protected by the 60 amp breaker in the house panel. My next thought was that maybe I need a main breaker panel so that I have a way to shut off the power to the whole garage with one flip of a breaker. So what's code?

Keith

 

[wbrian63]

"I think" that code states you need to have a disconnect in sub panel if the feeder panel isn't within sight, or is more than a certain distance away.

Even if I'm off on the code issue, the convenience of being able to turn off the box when you're working inside is a benefit. I've got a lugs sub-panel in my garage, and I've shocked myself more than once while working in the box. If I had a mains box, that wouldn't be an issue.

 

[sberry]

In a detached building you need disconnecting means, main breaker would likely be the easiest although you could back feed a breaker in a main lug panel.

 

[kmacht]

Ok, sounds like a Main Breaker it is. The cost difference is very little. HD has a 12 slot main breaker panel with 5 breakers for $35. It doesn't include the main breaker itself so I can size it to the 60 amps I want to feed it.

Keith

 

[Aceman]

Lately, I've been picking up Sq D QO 100A main breaker 20 space panels for about $7 less than a 16 space main lug. The most commonly used panel is usually going to be cheapest, so price it both ways.

I personally prefer main breaker panels because a main lug panel with a backfed breaker uses up at least 2-4 spaces.

 

[mrb]

get a bigger panel. 12 slots - 2 for the main and you only have 10 slots. spend an extra $20 on a bigger panel now, or youre going to spend 2 or 3 times that on twin breakers later.

make sure you get the hold down kit for the backfed main and mind where you put the breaker. Some panels only have one pair of slots where the holddown kit can be attached.

 

[kmacht]

The panel I looked at had 12 slots not including the main breaker slot. The main breaker slot was centered up above the other slots. I can't imagine needing more than 12 circuits in a 24x24 garage.

Keith

 

[mrb]

The panel I looked at had 12 slots not including the main breaker slot. The main breaker slot was centered up above the other slots. I can't imagine needing more than 12 circuits in a 24x24 garage.

Keith

a regular 60 amp breaker isnt going to fit in the main breaker slot. That panel you are looking at is a convertable main lug to main breaker, uses a different type of breaker for the main.

 

[kmacht]

Good to know. I'll have to take a closer look to see what type of breaker it needs in the top slot the next time I am at HD.

Keith

 

[Charles (in GA)]

You could also have a disconnect outside the building, it doesn't have to be on the building. A large weatherproof disconnected that is "service equipment" rated is OK and you could use the main lug panel.

Buy a large enough main breaker panel, such as a 20 space/30 breaker panel with a 100 amp main breaker, and you will be ready for later when you run a large cable, if you ever do.

Lots of options, look at prices and size and also at combo packs that come with breakers in them. As noted, the best selling will be the better price for what you are getting.

Charles

 

[1500hd]

The sub panel main breaker can be 100 amp. The feeder wires are protected by the 60 amp breaker in the house.