Feeder Neutral Disconnection

[iwire]

Wow, have never heard of that around here. I have never checked but it seems I have heard the power company was aware of the issue of going over 10,000 on a residence so they don't

There are areas around Boston and Cambridge where single family homes are supplied with 208/120 single phase from a three phase network and because the utility parallels sources on these networks the AIC can be quite high. Also requires a 5 jaw meter socket be used.

 

[jap]

I was just asked about this 4-pole disconnect switch that switched both the 3? ungrounded conductors and the neutral conductor. My comment was that as long as there was no fuse in place the neutral is permitted to be opened when opening all of the ungrounded conductors, others disagreed but could say where to find it in the NEC. Isn't this permissible? BTW an engineer designed this way (4-pole switch) for an unknown reason.

What is this? Is this a disconnect or is it actually a Tranfer switch? Looks like there's 4 conductors on the neutral on the top,,,, cant see what's on all of the others.
Heck I can't even see the blades of the switch unless they're behind the front panel somewhere.

If this has been there a while what's if feeding ? since the handle is down and there seems to be no fuses present ?

 

[GoldDigger]

What is this? Is this a disconnect or is it actually a Tranfer switch? Looks like there's 4 conductors on the neutral on the top,,,, cant see what's on all of the others.
Heck I can't even see the blades of the switch unless they're behind the front panel somewhere.

If this has been there a while what's if feeding ? since the handle is down and there seems to be no fuses present ?

Are those bolts and nuts on the vertical tabs intended for attaching lug type fuses? If not, what are they there for?
Are the breaking contacts for the disconnect behind the red plastic pieces in the upper section? I also cannot see anywhere else that they could be except behind the "fuse" space, which in that case would not be intended to hold fuses. Otherwise the fuses and the switch contacts would be in parallel.

 

[jim dungar]

Looks like there's 4 conductors on the neutral on the top,,,, cant see what's on all of the others.

It looks like a 200% neutral application. There are definitely 4 neutral conductors and only 2 line conductors (look at the terminal screws and openings at the bottom lugs).

 

[Smart $]

What is this? Is this a disconnect or is it actually a Tranfer switch? Looks like there's 4 conductors on the neutral on the top,,,, cant see what's on all of the others.
Heck I can't even see the blades of the switch unless they're behind the front panel somewhere.

If this has been there a while what's if feeding ? since the handle is down and there seems to be no fuses present ?

Not a transfer switch. Top and bottom back of enclosure have been cut out for wire entry/exit.

Appears to be only two ungrounded conductors per Line. Probably an implementation of 200% neutral, slightly downsized.

Are those bolts and nuts on the vertical tabs intended for attaching lug type fuses? If not, what are they there for?
Are the breaking contacts for the disconnect behind the red plastic pieces in the upper section? I also cannot see anywhere else that they could be except behind the "fuse" space, which in that case would not be intended to hold fuses. Otherwise the fuses and the switch contacts would be in parallel.

Blades are behind the red plastic arc shields. You can see part of the tips exposed through the slots in the red plastic pieces.

Bolts/nuts are for bolt-in fuses.

 

[infinity]

It's a 4 Pole fused disconnect with 200% neutral.

 

[kwired]

while we are questioning such things - why are there 8 EGC's? Probably 4 raceways with one per raceway, what are the other 4? Bonding jumpers?


I think I see a grounding bushing in the top left area.

 

[infinity]

while we are questioning such things - why are there 8 EGC's? Probably 4 raceways with one per raceway, what are the other 4? Bonding jumpers?


I think I see a grounding bushing in the top left area.

There are two per raceway, each raceway also has a bonding bushing. I believe that initially this was setup for an IG system and then the IG idea was scraped after the extra "IG" conductors were installed. If I remember correctly this fed a distribution board for a theater.

 

[jap]

Not a transfer switch. Top and bottom back of enclosure have been cut out for wire entry/exit.

Appears to be only two ungrounded conductors per Line. Probably an implementation of 200% neutral, slightly downsized.


Blades are behind the red plastic arc shields. You can see part of the tips exposed through the slots in the red plastic pieces.

Bolts/nuts are for bolt-in fuses.

I'm just curious what this is mounted over since they cut the back out of the disconnect on top and bottom and lined the cut out with what looks like a split black hose.
That was my question of "What is this?" its definitely a 4p fused switch without the fuses.... just wondering what it was mounted over.??

JAP>

 

[infinity]

I'm just curious what this is mounted over since they cut the back out of the disconnect on top and bottom and lined the cut out with what looks like a split black hose.
That was my question of "What is this?" its definitely a 4p fused switch without the fuses.... just wondering what it was mounted over.??

JAP>

Given the fact that the load conduits entered on the top and the line entered the bottom the installer used a large box (size of switch) behind the switch and cut windows to allow the conductors to enter in the correct line/load orientation. They used an edge-guard material on the cut metallic edges. I might be able to dig up a side view photo.