200A feeder tapped to multiple panels

[greenspark1]

I have a 200A breaker feeding a 200A panel but before the panel it's tapped with 3/0 conductors to another 200A panel (w/o a MCB). Technically this isn't a tap (240.2) because the 3/0 wires are protected by the 200A breaker. I don't like it, but is it a Code violation? I'm not seeing anything in the Code prohibiting it.

 

[infinity]

Just a splice and code compliant.

 

[iwire]

I agree with Rob and will point out that the NEC would allow a 200 amp feeder to supply as many panels as you want. The only limiting factor is the total load as calculated by article 220.

 

[greenspark1]

I agree with Rob and will point out that the NEC would allow a 200 amp feeder to supply as many panels as you want. The only limiting factor is the total load as calculated by article 220.

Great, appreciate the feedback. One of things that looks bad when you see it, but when you dig into it realize no Code restriction. Of course our specs usually say feeders must be continuous and unspliced

 

[kwired]

Of course our specs usually say feeders must be continuous and unspliced

No 400, 600 amp service disconnecting means supplying multiple 100 and 200 amp devices using feeder tap rules? A real common application where a feeder gets "spliced".

A panelboard with "main lugs" and "subfeed lugs" results in an extension of the feeder that supplies the panelboard.

 

[iwire]

Great, appreciate the feedback. One of things that looks bad when you see it, but when you dig into it realize no Code restriction. Of course our specs usually say feeders must be continuous and unspliced

Let me say that there is nothing bad or wrong with feeder splices.

In my personal opinion specifications that require continuos feeders are foolish.

 

[greenspark1]

Let me say that there is nothing bad or wrong with feeder splices.

In my personal opinion specifications that require continuos feeders are foolish.

No offense taken. More electrical issues occur at splices/connections than continuous wire. So the intent is to reduce risk. I don't think taps are necessarily bad, but more complicated and rely on the contractor a bit more. A couple months back at a hospital I saw 3 sets of 750 kcmil 'spliced' into 4 sets of 500' kcmil with polaris blocks rated 500-#4. An example of how even simple stuff can easily get messed up.

 

[jap]

No offense taken. More electrical issues occur at splices/connections than continuous wire. So the intent is to reduce risk. I don't think taps are necessarily bad, but more complicated and rely on the contractor a bit more. A couple months back at a hospital I saw 3 sets of 750 kcmil 'spliced' into 4 sets of 500' kcmil with polaris blocks rated 500-#4. An example of how even simple stuff can easily get messed up.
View attachment 17203

What exactly is that in the picture?
It looks like an open rack splice instead of the inside of a panelboard or J-box.

JAP>

 

[iwire]

No offense taken. More electrical issues occur at splices/connections than continuous wire. So the intent is to reduce risk.

I understand the intent, and with reasonable length conductors that is an easy goal to achieve.

On the other hand requiring long complicated pulls to be done continuous is counter productive. The likelihood of insulation damage becomes a real factor. Either from sidewall pressure or from laying the cable out on the ground at a pull point.

Instead of a specification saying 'no splices' it makes more sense to me to specify the manor used for splicing.

 

[greenspark1]

What exactly is that in the picture?
It looks like an open rack splice instead of the inside of a panelboard or J-box.

JAP>

Yup, splice on a cable rack.

 

[jap]

Yup, splice on a cable rack.

Something about the use of that type of connection as an open splice on a cable rack just doesn't seem right.

JAP>

 

[kwired]

Something about the use of that type of connection as an open splice on a cable rack just doesn't seem right.

JAP>

I would assume this falls under art 392 Cable trays. 392.56 does allow that.

 

[jap]

I would assume this falls under art 392 Cable trays. 392.56 does allow that.

I'm sure it probably does. I'm just not a fan of exposed live conductors in a cable tray.

JAP>

 

[kwired]

I'm sure it probably does. I'm just not a fan of exposed live conductors in a cable tray.

JAP>

They are insulated/covered conductors, isn't such installation limited to areas with qualified persons servicing them to start with?

Different story then if you ran this tray in a readily accessible location in the main corridor in a public access building.

 

[jap]

They are insulated/covered conductors, isn't such installation limited to areas with qualified persons servicing them to start with?

Different story then if you ran this tray in a readily accessible location in the main corridor in a public access building.

The conductors are insulated, but the end of the Polaris connector where the wire goes into the connector is not.
Therefore, the termination is not completely insulated.

Not sure if the OP's picture is in an area where only qualified persons are servicing them or not.

JAP>

 

[petersonra]

The conductors are insulated, but the end of the Polaris connector where the wire goes into the connector is not.
Therefore, the termination is not completely insulated.

Not sure if the OP's picture is in an area where only qualified persons are servicing them or not.

JAP>

however there is an insulated shroud that comes out over the wire. the only place there is access to the energized conductor is between the shroud and the conductor insulation. given it is in a controlled area, one would think it is pretty safe. you would have to almost deliberate stick something conductive between the shroud and the conductor to access the live part of the connector.

 

[jap]

however there is an insulated shroud that comes out over the wire. the only place there is access to the energized conductor is between the shroud and the conductor insulation. given it is in a controlled area, one would think it is pretty safe. you would have to almost deliberate stick something conductive between the shroud and the conductor to access the live part of the connector.

It is still an uninsulated connection and deliberate or not, that's how most accidents happen.
The picture just happens to show the connection on a grounded conductor but it could be a phase conductor just as easily.

I wouldn't use a splice in a cable tray that wasn't completely insulated regardless of whether it was a controlled area or not.

A lot of human intervention takes place when pulling conductors into an existing cable tray, which leaves much more opportunities for something to get into the connection that is not completely insulated.

JAP>

 

[petersonra]

It is still an uninsulated connection and deliberate or not, that's how most accidents happen.
The picture just happens to show the connection on a grounded conductor but it could be a phase conductor just as easily.

I wouldn't use a splice in a cable tray that wasn't completely insulated regardless of whether it was a controlled area or not.

A lot of human intervention takes place when pulling conductors into an existing cable tray, which leaves much more opportunities for something to get into the connection that is not completely insulated.

JAP>

you are of course free to add some electrical tape around that tiny gap between the shroud and the conductor.

 

[jaggedben]

I don't agree that the polaris block is an uninsulated connection. However the fact that the incorrect size block was used and a band-aid was put on in the form of (apparently) taping over exposed metal conductor is violating the listing of the terminal block and poor workmanship. If the block was correctly sized then the conductor insulation would fit inside the block insulation and would be effectively insulated.

 

[petersonra]

I don't agree that the polaris block is an uninsulated connection. However the fact that the incorrect size block was used and a band-aid was put on in the form of (apparently) taping over exposed metal conductor is violating the listing of the terminal block and poor workmanship. If the block was correctly sized then the conductor insulation would fit inside the block insulation and would be effectively insulated.

I don't think so. Those blocks can accept a wide range of conductors. sometimes down to #10 or so. There is always going to be some space where if you really tried you could get to the hot stuff.

In any case, there is nothing wrong with taping over the exposed metal conductor. It is a perfectly acceptable way of insulating the end of the conductor. It is maybe not as attractive as some other method but that does not mean it is unacceptable.

I don't think the block is the wrong sized block either. i think someone just stripped off too much insulation.