Disconnect in Subpanel Feed to Garage?

[wallyblackburn]

In the interest of full disclosure, I'll start off by explaining *why* I want a service disconnect. It's a sad tale that's been told before... I ran 2-2-2-4 MHF out to my new shop. Trenched it in, risers on sides of shop/house, conduit down to over 18 inches. Pretty proud of myself...until I figured out I was about 4-5 feet short of my breaker box in house! Not even gonna go into how I think it happened - it did so it's my fault. It's already covered - I am not replacing it.

Here's my setup:

House: 200A Square-D Homeline panel
Shop: 100A Square-D Homeline panel
Feeder: *Supposed* to be 120' of 2-2-2-4 MHF Al

2 ground rods at shop, ground and neutral separate in shop.

So, I figured I could do a junction box, but why not do a service disconnect in basement? It could be nice to be able to lock out power to garage - and it would even look like I planned it that way! So, I'm looking at something like:

http://www.homedepot.com/p/GE-100-Amp-240-Volt-Fusible-Indoor-General-Duty-Safety-Switch-TG3223/202978655?N=5yc1vZbm0hZ1z11za5

I will switch the 2 hots, put a ground bus inside disconnect box, and splice neutral with a barrel splice with white shrink wrap.

Is this workable? Ideas for improvement?

Really appreciate any advice,
Thanks, Wally

 

[Stuart in MN]

You can use a disconnect switch, no problem. Just keep the neutral and ground wires separate.

edit: that particular disconnect switch is fused, which you don't need. You can use a non-fused disconnect switch as well, although it will depend on what you can find at your local store and for what price.

edit x2: you should also be able to get a neutral kit for that disconnect, so you'll have separate termination points for the ground and neutral. That way you don't have to mess around with a barrel splice. They're shown on page 4-24 of this GE catalog. http://www.geindustrial.com/catalog/buylog/04_BuyLog2013_SafetySwitches.pdf

 

[Mustang51js]

I would just use a junction box,you have a disconnect 5 feet away in your panel and could buy a lock out for the breaker if you had to. Just seems like a waste of money for the disconnect

 

[PRH44]

First things first you are using this as a feeder not as service entrance conductors. #2 AL MHF cable in this application is good for 90 amp at 75 degree Celsius. Not 100 amp as the specification sheet states. So you need a 90 amp breaker in the house panel.
You can use a box to splice the conductors and save your self the cost of a disconnect.
However if you are set on using a disconnect, you do not need a fused disconnect you can use a non fused style and save the cost of fuses. Use an insulated neutral bus kit in your disconnect.

 

[wyliesdiesels]

I would just use a junction box,you have a disconnect 5 feet away in your panel and could buy a lock out for the breaker if you had to. Just seems like a waste of money for the disconnect

My thoughts also. Why waste the money.

BTW OP did u breaker the MHF at 90a?

 

[wallyblackburn]

First and foremost: A SINCERE THANKS TO ALL FOR YOUR REPLIES!

I appreciate the comments and advice more than you can imagine. So, here is what I am taking away:

- I can do this
- I don't need a fused disconnect - non-fused is cheaper
- I could even just use a junction box to save $$$
- *** I should breaker this at 90A or less in my main panel ***

Thanks again,
Wally

 

[wallyblackburn]

Back again...

Let's say I did just splice in a junction box. What type of splices could I use to get a good job without buying $200 special crimpers or similar?

The GE neutral kit shown in one reply - lowest price online is $66! What am I missing? The whole disconnect I am looking at is only $85.

Thanks again,
Wally

 

[brewchief]

Back again...

Let's say I did just splice in a junction box. What type of splices could I use to get a good job without buying $200 special crimpers or similar?

The GE neutral kit shown in one reply - lowest price online is $66! What am I missing? The whole disconnect I am looking at is only $85.

Thanks again,
Wally

You can use split bolts and tape or a polaris or burndy connector, the polaris or burndy will be more expensive then split bolts but is easier to use and quicker.

If you use a metal junction box don't forget that it needs to be grounded as well.

 

[Mustang51js]

Split bolts and rubber tape prob cost you $20 tops,they do have barrel style lugs with set screws on each side also but normally they want a non reversible style crimp