What 50 amp disconnect should I use for a garage?

[dhalleron]

I'm a licensed Master and haven't posted here for quite a while. I only did electrical work part-time for the past 33 years. I mostly do fire alarms.

I am helping someone install a 50 amp underground feeder to a garage in Indiana. I understand they are still on 2008 NEC and we probably don't need a disconnect outside the building. We installed a main lug-only panel, so I decided on a disconnect anyway. The disconnect I had lying around was 60 amp, but it only had 2 terminal screws for the ground and no place to terminate the ground rod GEC or the neutral.

I don't use a supply house much anymore, since I rarely do this work. I've been looking at Home Depot, Lowes, and Menards websites. They mostly don't show enough detail to tell if a particular disconnect is suitable for my use. Also, prices are all over the board from 20 bucks to 200 bucks.

Am I thinking this through correctly? Suggestions anyone? Thanks.

Dale

 

[roger]

The neutral can feed through straight to the panel and you can buy a ground bar that will accommodate the EGC and GEC if you need more terminals.

 

[ptonsparky]

I would back feed a 60 in the MLO panel. You would need a tie down for that breaker. 4 wire feeder with GES to the EG bar that is bonded to the enclosure. Neutral would float.

 

[dhalleron]

The neutral can feed through straight to the panel and you can buy a ground bar that will accommodate the EGC and GEC if you need more terminals.

Thanks Roger. I thought about feeding the neutral straight through. There doesn't seem to be much room to add a terminal to this disconnect I had on the shelf. I know we are supposed to use the one listed by the manufacturer. Square D disconnect at Lowes

 

[dhalleron]

I would back feed a 60 in the MLO panel. You would need a tie down for that breaker. 4 wire feeder with GES to the EG bar that is bonded to the enclosure. Neutral would float.

I thought about that too. I was thinking it would be best to have an outside disconnect, but if it's not required...

 

[ptonsparky]

Not required but it should be close to the point of entry into the building. The MLO would be on a perimeter wall. Inside.

 

[roger]

If you feed the neutral straight through the existing two terminals will be all you need

 

[dhalleron]

Not required but it should be close to the point of entry into the building. The MLO would be on a perimeter wall. Inside.

That's the other thing, I wasn't sure about. I don't remember what the older codes said about distance inside the building. This panel is on the rear wall maybe 20 feet from the door. I'm still thinking I want a disconnect outside.

 

[dhalleron]

If you feed the neutral straight through the existing two terminals will be all you need

Don't I need to terminate my ground rod GEC at the disconnect? Or are you saying it could be terminated at the panel? I thought it had to be at the first means of disconnect.

 

[ptonsparky]

A 2 pole 3R enclosure containing a 60 amp breaker.

 

[roger]

Don't I need to terminate my ground rod GEC at the disconnect? Or are you saying it could be terminated at the panel? I thought it had to be at the first means of disconnect.

Yes you can land it at the panel

 

[ptonsparky]

A 60 amp AC disconnect. Let the neutral float.

 

[wwhitney]

The neutral can feed through straight to the panel

Since the interior panel is MLO and has no disconnect, I believe that would be a violation of 225.38(C). From the 2017 NEC:

"(C) Disconnection of Grounded Conductor. Where the building or structure disconnecting means does not disconnect the grounded conductor from the grounded conductors in the building or structure wiring, other means shall be provided for this purpose at the location of the disconnecting means. A terminal or bus to which all grounded conductors can be attached by means of pressure connectors shall be permitted
for this purpose."

The outside disconnect is the only disconnecting means provided, so means for disconnecting the grounded conductor must be provided at that location, rather than just at the interior MLO panel.

Cheers, Wayne

 

[ptonsparky]

Since the interior panel is MLO and has no disconnect, I believe that would be a violation of 225.38(C). From the 2017 NEC:

"(C) Disconnection of Grounded Conductor. Where the building or structure disconnecting means does not disconnect the grounded conductor from the grounded conductors in the building or structure wiring, other means shall be provided for this purpose at the location of the disconnecting means. A terminal or bus to which all grounded conductors can be attached by means of pressure connectors shall be permitted
for this purpose."

Cheers ,Wayne

A Blue wire connector on the neutral would suffice.

 

[roger]

Since the interior panel is MLO and has no disconnect, I believe that would be a violation of 225.38(C). From the 2017 NEC:

"(C) Disconnection of Grounded Conductor. Where the building or structure disconnecting means does not disconnect the grounded conductor from the grounded conductors in the building or structure wiring, other means shall be provided for this purpose at the location of the disconnecting means. A terminal or bus to which all grounded conductors can be attached by means of pressure connectors shall be permitted
for this purpose."

The outside disconnect is the only disconnecting means provided, so means for disconnecting the grounded conductor must be provided at that location, rather than just at the interior MLO panel.

Cheers, Wayne

I guess I should have spliced and fed through to the panel

 

[dhalleron]

Since the interior panel is MLO and has no disconnect, I believe that would be a violation of 225.38(C). From the 2017 NEC:

"(C) Disconnection of Grounded Conductor. Where the building or structure disconnecting means does not disconnect the grounded conductor from the grounded conductors in the building or structure wiring, other means shall be provided for this purpose at the location of the disconnecting means. A terminal or bus to which all grounded conductors can be attached by means of pressure connectors shall be permitted
for this purpose."

The outside disconnect is the only disconnecting means provided, so means for disconnecting the grounded conductor must be provided at that location, rather than just at the interior MLO panel.

Cheers, Wayne

Good catch. I see that verbiage is in the 2008 edition as well.

 

[dhalleron]

A Blue wire connector on the neutral would suffice.

I was told by someone I can't use a wirenut on #6 wire and didn't question it. Now I see on the label for the blue Ideal 454 it is suitable for 1 or 2 #6. But to get picky the code seems to require a terminal or bus and says:
A terminal or bus to which all grounded conductors can be attached by means of pressure connectors shall be permitted
for this purpose.

 

[wwhitney]

I was told by someone I can't use a wirenut on #6 wire and didn't question it. Now I see on the label for the blue Ideal 454 it is suitable for 1 or 2 #6. But to get picky the code seems to require a terminal or bus and says:
A terminal or bus to which all grounded conductors can be attached by means of pressure connectors shall be permitted
for this purpose.

The statement "X shall be permitted" does not in any way mean "not X is not permitted."

Cheers, Wayne

 

[ptonsparky]

I was told by someone I can't use a wirenut on #6 wire and didn't question it. Now I see on the label for the blue Ideal 454 it is suitable for 1 or 2 #6. But to get picky the code seems to require a terminal or bus and says:
A terminal or bus to which all grounded conductors can be attached by means of pressure connectors shall be permitted
for this purpose.

Shall does not equal Require.

 

[roger]

Well use polaris lug.