Panel ran in Series

[iwire]

Maybe i miss used the word 'main' in this context. Im talking about a breaker in panel 'A" that would feed panel 'B"

I understand that. :smile:

In that case you could work in panel B without PPE.

But the line side of the breaker in Panel A will still be hot so the PPE rules would still be required ..... in my opinion.

So what I am saying is that a panel with a main breaker in the same enclosure as the panel never relieves you of the hot work rules, you would have to shut off the feeder back at the source.

I can see your point about it being a poor design in a hospital situation as shutting off 84 or 126 circuits at any time of day will be more difficult then 'just' 42 circuits.

But still it comes down to money, less main breakers = less cost at the time of construction, I agree with you in the long run it may end up costing more.

For what it's worth the CEC (Canadian Electric Code) requires the line side of the service disconnect to still be totally enclosed when you open the normal panel cover. I am not sure if this only applies to dwelling units or service panels.

Nice rule in my opinion, means you can shut off the main in a residential panel and be entirely guarded from live parts. For me dealing with bare grounds in a live dwelling unit panel always made me nervous.

 

[brian john]

In 35 years of performing maintenance with schedule power outages (three this week end) I have never seen this as an issue. Now if you want to install a main as you perform your work I am sure the end user would appreciate it.

The point is and will always be (unless the NEC addresses this). The cost (in most cases) is not justified by an occasional outage.

If you read my post you will see I said COMMERCIAL BUILDINGS........

Additionally I would think (but I could be wrong) that in hospitals, data centers and the like this issue is weighed, cost versus convenience.

Lastly with stricter realizations about working hot you may see more mains in panels. BUT the dollar did, does and will rule unless codes dictate otherwise.

 

[brother]

In 35 years of performing maintenance with schedule power outages (three this week end) I have never seen this as an issue. Now if you want to install a main as you perform your work I am sure the end user would appreciate it.

The point is and will always be (unless the NEC addresses this). The cost (in most cases) is not justified by an occasional outage.

If you read my post you will see I said COMMERCIAL BUILDINGS........

Additionally I would think (but I could be wrong) that in hospitals, data centers and the like this issue is weighed, cost versus convenience.

Lastly with stricter realizations about working hot you may see more mains in panels. BUT the dollar did, does and will rule unless codes dictate otherwise.

I understand your point, but in this scenerio, i believe it would have been more PRUDENT and COST$ effective to have the main (feeder breaker) installed. No disrespect toward your 35 yrs of experience but it seems like the FEW times ive run into this scenerio, it was always cheaper to have that feeder breaker than all this 'scheduled' shut down.

When I add up the cost$ of having to shut off everything in the other panel just to work on panel being fed off the buss, its actually lot more. People dont seem to count all the 'phantom' cost of having to rearrange/schedule and sometimes move employees (the cost of this time doing this overhead etc) and to look at more lost of production in some scenerios. Im not even adding the labor for the electricians to actually do the work, just the overhead and production/employees.

Just for grins, i checked to see how much it would cost for the most expensive type of breaker i could find even though the actual one(westinghouse) for this panel is less. It was found at grainger and it was for 3,800 est 3 pole 225 amp 480v. Well when (in a hospital) you get a head nurse involved so they can be sure the patients are not affected adversely due to the power outage, and the other employees and their time involved that per hour scale (remember they get paid benefits too)adds up. Not to mention the paper work involved.

Even in non hospital enviroments it just doesnt seem people count up the costs involved to make sure that proper safety precautions are tallied. TIME is money and there will be 'phantom costs.

So yes, the dollar does and will rule unless codes dictate otherwise, but people need to know what the REAL dollar$ are. Because i really dont think do.

 

[brian john]

Weight the few times against the 1000's maybe 100,000's of riser systems out there that have never been shut down. I think the scales would tip towards the risers. Just my opinion I have been wrong before (I think).

 

[jim dungar]

It is very easy to build a panel with a main breaker at one end of the bus and a set of feed-through lugs at the other end.

It is very expensive to build a panel with a 100-200A main breaker that can accept multiple sets of conductors for "in and out" sub-feeds.

Now, maybe this is just because of "supply and demand", but it is what it is.

You are, of course, free to design your multi-tub panels which ever way you want and are willing to pay for. I have seen a single trim designed to cover a triple tub flush mount panel.

 

[brother]

It is very easy to build a panel with a main breaker at one end of the bus and a set of feed-through lugs at the other end..

I do not dispute this.

It is very expensive to build a panel with a 100-200A main breaker that can accept multiple sets of conductors for "in and out" sub-feeds..

I do not dispute this either, but i failed to see the point of it. since I was suggesting that this panel 'A" just have a 'branch' circuit breaker installed that would feed panel 'B"

Now, maybe this is just because of "supply and demand", but it is what it is.

You are, of course, free to design your multi-tub panels which ever way you want and are willing to pay for. I have seen a single trim designed to cover a triple tub flush mount panel.

Interesting comment.

 

[Pierre C Belarge]

Just Reading Thru....

Just Reading Thru....

What peaks my interest here is how the industry is going to move forward from here.

Most people in our industry are aware of OSHA. Most people in our industry have never seen OSHA on a jobsite.
Most are not fully aware of the requirements or the changes headed our way.
One statistic that stands out when discussing this and I think has a profound impact on this situation for the present is, AGE.

The age ratio in our industry is such that many, many of the electricians really never had to deal with PPE or safety in the manner it is being discussed. Because of that, there is a pervading feeling that the consequences are not as severe and most of them think that the results of all the conversation/discussion of safety will not directly affect them before they retire. Hence, the lack of action towards implemetation.


One other thought.
The actual use of PPE and safety training is fairly constant and growing in two segments of our industry.
1. larger companies

2. industrial plants, etc...

but most of the electricians in this country work for smaller companies.
So...cost and enforcement become another aspect of the reasons why this is such a monster to deal with presently.

 

[brother]

What peaks my interest here is how the industry is going to move forward from here.

Most people in our industry are aware of OSHA. Most people in our industry have never seen OSHA on a jobsite.
Most are not fully aware of the requirements or the changes headed our way.
One statistic that stands out when discussing this and I think has a profound impact on this situation for the present is, AGE.

The age ratio in our industry is such that many, many of the electricians really never had to deal with PPE or safety in the manner it is being discussed. Because of that, there is a pervading feeling that the consequences are not as severe and most of them think that the results of all the conversation/discussion of safety will not directly affect them before they retire. Hence, the lack of action towards implemetation.


One other thought.
The actual use of PPE and safety training is fairly constant and growing in two segments of our industry.
1. larger companies

2. industrial plants, etc...

but most of the electricians in this country work for smaller companies.
So...cost and enforcement become another aspect of the reasons why this is such a monster to deal with presently.

Well like one person said, its not gonna change until we in the industry make it change.

 

[iwire]

I do not dispute this either, but i failed to see the point of it. since I was suggesting that this panel 'A" just have a 'branch' circuit breaker installed that would feed panel 'B"

This will often be expensive.

The panels will be designed for 42 circuits of 100 amp or less frame size.

To provide a 225 breaker for the next panel requires the panel shop to build the panel with a 225 amp sub feed spot and you also lose three more spaces for a breaker that is not really required.

My suggestion is you stop thinking of it as separate panels but just one large panel as that is how it is designed. :smile:

Keep in mind I did see your point and agree with you about this not being a great design for a hospital. :smile:

But change the location to an office building with lots of modular office furniture (Office cubes) and the double or triple tub is an excellent choice.

 

[jflynn]

This will often be expensive.

The panels will be designed for 42 circuits of 100 amp or less frame size.

To provide a 225 breaker for the next panel requires the panel shop to build the panel with a 225 amp sub feed spot and you also lose three more spaces for a breaker that is not really required.

My suggestion is you stop thinking of it as separate panels but just one large panel as that is how it is designed. :smile:

Keep in mind I did see your point and agree with you about this not being a great design for a hospital. :smile:

But change the location to an office building with lots of modular office furniture (Office cubes) and the double or triple tub is an excellent choice.

Bob is right on here,the double tub set up is very common.Also,- as far as having the ability to shut down panels in lieu of scheduling shutdowns may in fact put your customer(s)or even worse YOU in a situation that need not be.We all to often think we have taken the correct measures to insure we have a circuit/feeder locked out to safely work on it,only to forget one vital step and then its to late-customers in my opinion when educated about the risk of working on systems that can potentially do more harm to there operations then in-convience them...