Ground rod at detached garage?

[cobragrover]

I plan on putting a 60 amp breaker in the box in the house and run 2-2-2-4 AL URD underground in conduit to my detached garage. I had to upsize the wire size because it is an 85 ft run to the panel in the garage. I'm going to have my ground attached to the ground in the house and the ground in the garage panel. My question is do I need to add a ground rod at the garage? I've been reading varied opinions.

Thanks

 

[theoldwizard1]

NO! The reason there are 4 conductors is one of them is for ground.

Also, you don't want URD, you want MHF ! It is also cheaper.

 

[Stuart in MN]

YES! A ground rod is required, see NEC article 250.32, parts A and B.

 

[walrus]

yes you need ground rods

 

[wyliesdiesels]

I plan on putting a 60 amp breaker in the box in the house and run 2-2-2-4 AL URD underground in conduit to my detached garage.

URD is not permitted inside a structure.

Are you transitioning to another cable type on each end?

MHF would be easier as its permitted inside...

I had to upsize the wire size because it is an 85 ft run to the panel in the garage.

85' is not that long of a run.

you could put #2 al on a 90a breaker and not have issues with voltage drop.

I'm going to have my ground attached to the ground in the house and the ground in the garage panel. My question is do I need to add a ground rod at the garage? I've been reading varied opinions.

Thanks

You are confusing 2 different things. An EGC aka ground wire, that goes between the panels, is NOT the same thing nor has the same function as a grounding electrode. DO NOT confuse the 2.

The EGC between panels is to provide a low impedance fault current pathway.

Grounding electrodes do not and cannot do this. They are for grounding lightening, limiting voltage to earth, and shunting higher voltage primary lines when they contact secondary lines.

YES! you definitely need grounding electrodes. code requires 2 unless you can prove 25ohms or less resistance to earth with one.

Also, not sure why or where you're getting varied "opinions" on this as this is a VERY clear topic. I'm thinking you're getting info from people who don't understand basic concepts and differences between EquipmentGroundingCconductors & grounding electrodes.

NO! The reason there are 4 conductors is one of them is for ground.

Also, you don't want URD, you want MHF ! It is also cheaper.

Completely WRONG. Come'on. youve been here long enough to know this.

The EGC between panels is not for shunting lightening.

you are confusing 2 different things.

 

[ard]

The EGC between panels is not for shunting lightening.

No, thats why we have an Ethernet cable....



(jk)

 

[firedudetl1]

sticking my nose into this....
do yourself a favor and either get an electrician friend to help you out or bite the bullet and hire someone to get it done right
no offense to anyone here, but this is one of those times that getting the "right guy" involved could keep you from burning down your house or your shop.....or getting yourself killed....
if anyone on here is an electrician, they could probably help you out since NFPA 70 is the national electrical code but you should still have someone local help you

 

[Kaizen]

While we are in the topic. Two rods six feet apart I get. Does the first one have to be any specific distance from the panel? Is bare copper used or is it better to use sheathed wire and strip it at the ground attachments? How does it get from an inside panel to the ground? Should it be in conduit? Or just stapled to building?


Sent from my iPhone using The Garage Journal mobile app

 

[cobragrover]

Sorry, my bad. I was thinking the ground rod at the house might serve as ground to earth. So I should put 2 ground rods at least 6 ft apart at the garage. I should use MHF wire from box to box. As far as wire size I plugged the distance into a Southwire voltage drop calculator and I think it told me to upsize because of the 85 ft run. That's why I said 2 gauge AL.

 

[wyliesdiesels]

What are your loads?

 

[cobragrover]

I don’t have much planned for the garage. Just lights outlets, air compressor, contractors table saw, miter saw. Maybe a wire welder in the future. No a/c or furnace.

 

[wyliesdiesels]

whats the HP rating on the compressor motor?

 

[wyliesdiesels]

While we are in the topic. Two rods six feet apart I get. Does the first one have to be any specific distance from the panel? Is bare copper used or is it better to use sheathed wire and strip it at the ground attachments? How does it get from an inside panel to the ground? Should it be in conduit? Or just stapled to building?


Sent from my iPhone using The Garage Journal mobile app

no minimum distance from panel

bare solid copper is usually used. If #6 then no protection is required ie conduit. If #8 then it needs to be sleeved in conduit.

Can attach to building. you would drill a hole to exit it from the building. Or do you have a hole for conduit where it can exit?

Sorry, my bad. I was thinking the ground rod at the house might serve as ground to earth. So I should put 2 ground rods at least 6 ft apart at the garage. I should use MHF wire from box to box. As far as wire size I plugged the distance into a Southwire voltage drop calculator and I think it told me to upsize because of the 85 ft run. That's why I said 2 gauge AL.

the ground rod at the house would not be sufficient. and code requires 2 rods regardless.

the southwire calculator is not always accurate.

 

[cobragrover]

I don't remember the hp of the compressor. It's a standard 110volt 30gal compressor from Tractor Supply. Not the oil free. Learned the hard way on those.

 

[Falcon67]

I don’t have much planned for the garage. Just lights outlets, air compressor, contractors table saw, miter saw. Maybe a wire welder in the future. No a/c or furnace.

I run my 960 sq/ft shop off 2-2-2-4 MHF, 130' run, 70A breaker. Dual AC units, 5kW heater, two lathes, mill, welder, 60 gallon 3.5HP compressor, lift, etc, etc. No issues. Use the MHF, it's plenty and cheaper. I used a 70A breaker vs a 90A because HD had the 70A on the shelf, had to order the 90. Nah.