Accept 4-144: Services to be Outside

[George Stolz]

This proposal would force all service disconnects to be mounted outside.

A main outdoor disconnect also creates a security issue where criminals could interrupt service to defeat security and communication equipment. A requirement to install a disconnect outside with the meter would present difficulties in inner-city environments where underground service conductors enter a building from underground distribution systems. The meters are in the basement, or in recessed enclosures on the front wall of the building. There is limited space on building walls in row home neighborhoods to add a main switch ahead of the meter. This would also present difficulties for facilities served at voltages over 1,000 Volts. The submitter has not presented any technical data to support such a change. Unqualified persons should never remove electric meters nor should they intentionally expose themselves to electrical hazards. Overcurrent devices installed outdoors where they are subject to corrosive environments many times fail or become inoperable for emergency situations.

1.) Comment on Proposal No.: 4-144
2.) Recommendation: Accept the proposal.
3.) Substantiation: To rebut each of the panel's ostensibly contrived statements:
1. All service disconnects I have seen have a means for locking the disconnect closed with a padlock, which is permissible by code. To claim that there is a security risk involved is misleading. Security and communication equipment often have means for continued use after power loss; security systems have battery backup, and POTS does not require local power to operate.
2. An exception can be added if the panel feels that inner city environments would be adversely affected by this change.
3. An exception can be added for services over 1000V.
4. Data was presented to the panel in the last code cycle (Proposal 4-132 2010 ROP) detailing two separate incidents which resulted in property damage explicitly because the service disconnects were allowed inside. It was remarkable in both incidents that there were no loss of life.
5. In the cases mentioned in item #4 above, no covers were removed by unqualified personnel - but covers were removed by arc blasts that could have claimed the lives of several people.
6. 240.24(D) already prohibits overcurrent devices from installation in corrosive environments, and this section does nothing to add to that concept.

Billions will be spent on AFCI breakers that may or may not make an impact on electrical safety. This proposal has no appreciable cost impact yet would make an indelible difference in safety to both workers and occupants. The panel should reconsider it's decision.

 

[kwired]

This is because of two incidents where property damage occured where service equipment was indoors??

Accidents never happen with outdoor service equipment??

Limitations on where it can be located indoors makes more sense than banning indoor locations altogether. We have banned locating this equipment in bathrooms and clothes closets in dwellings we could put more limitations on proximity to combustable materials and maybe should.

 

[iwire]

There are literally tens of thousands of buildings both dwelling units and non dwelling units in the cities around me with no place for an outdoor service disconnect.

I see you show and exception but the exception would become the rule making the need for the rule itself in question.

 

[jim dungar]

Probably the most common arc flash incident energy mitigation method I see, is to have a protective device 'remote' from the main service equipment.

But, what do we do when the utility transformer is inside an 'indoor vault'? How about when the utility requirements are to close couple their metering equipment to the customers service equipment?

 

[George Stolz]

I thought this might get a couple replies.

 

[kwired]

You might start to see services be inside a vault if this was the rule. Surely the vault will be considered outside for the purpose of this application.

 

[jim dungar]

You might start to see services be inside a vault if this was the rule. Surely the vault will be considered outside for the purpose of this application.

Utility vaults usually have restricted access by the customer.

 

[hurk27]

A few years ago a proposal like this was implemented here in Indiana, it was submitted when a local inspector/fire marshal tried to require the samething and found out they didn't have the authority to do so without the state amending the requirements for the whole state, when they were told no by the state AHJ they went over his head to the legislation members and had a bill drawn up, the whole requirement was based upon making it safer for firemen to turn off power to an involved structure, while it was brought up that many of the firemen had the training to use hot sticks to pull out the primary fuses they pointed out it wasn't in wide enough use that a disconnect would be better.

Many of the contractors and inspectors in Indiana banded together and flooded the state with opinion of why too or not too allow this bill to go through, most were against it because of the security issue you mentioned, others was because of the cost it would add to each and every service installed, even a 100 amp fused disconnect is pricey over a main breaker panel which around here is cheaper then a main lug panel of the same size, and for larger services it can get very expensive.

My main argument was the fact that so many older service would still be in existence, and the hot stick training would still be needed for years to come that would not out weigh the cost added to new services as the money would be better spent to train firemen to use the hot stick method to kill the power to an involved building.

We had a discussion on here back then when this went on, I'll try to find it.

 

[hurk27]

I found the old post about the above when this was tried to be put through Indiana

Click Here

 

[hillbilly1]

I can see this at possibly minimizing damage if the customer can shut off the power in an emergency instead of waiting on the fire department or poco to arrive. Not everybody lives within 5 minutes of a fire station.

 

[iwire]

I can see this at possibly minimizing damage if the customer can shut off the power in an emergency instead of waiting on the fire department or poco to arrive. Not everybody lives within 5 minutes of a fire station.

Can you describe a realistic scenario where this could help?

In my opinion service disconnects are not intended to be EPOs.

 

[cadpoint]

Jezz George, If your only comment is to state Accept or Reject and drop a statement, what's the point.

Put a poll on everything and let us vote.

 

[jim dungar]

I can see this at possibly minimizing damage if the customer can shut off the power in an emergency instead of waiting on the fire department or poco to arrive. Not everybody lives within 5 minutes of a fire station.

Then it becomes a design issue, not an NEC mandate.

 

[cadpoint]

OK, look up "design" in merriam-webster! OK, here's the link instead.

Fine let's go with intransitive verb...

 

[George Stolz]

Jezz George, If your only comment is to state Accept or Reject and drop a statement, what's the point.

Put a poll on everything and let us vote.

Not everything is a poll, Jude.

I'm mostly looking for arguments either way, which will sway the outcome of the comment.

 

[cadpoint]

Not everything is a poll, Jude.

I'm mostly looking for arguments either way, which will sway the outcome of the comment.

Fine, it also took me three readings of three differnet Dropped NEC's to understand that point. Don't get me wrong, I read and re-read, I'll stay with my statement.

If your's in nothing more than your comment of ... and nothing else but only " Accept or Reject ", than you haven't done nothing for those playing alone at the House. JMO.


Your own comment of accept or Reject is built in to the OP, Why Argue with George...

 

[hurk27]

I have a different angle to this idea that would not only give you the safety for fire personnel to remove power to a building but also make it much safer in pulling a meter to change out a meter.

My idea is to require meter bases with a line side disconnect built in to cold sequence the meter, some POCOs already require this for services, what if we were able to get a requirement that would require only 400 amp and below meters to have a built in feature that would allow the service entrance conductors to be disconnected, this would also increase the safety for POCO employees changing meters, as well as giving a place to kill the power to a building in an emergency.

One. there would be no requirement of relocating the service main disconnect point to the outside of the building because it would not have any OCPD so 4-wire feeder would not be required as an added cost.

Two. it would be a standard available meter base so the cost over a separate disconnect with OCPDs would be minimal.

Now we are offering safety to a wider group of people with a much less cost fiscal impact that can block many codes from being accepted, the exception to this requirement would be if a disconnect with OCPD's were installed.

I'm all for safety but lets keep the cost down when we implement it?

now I would say this approach would require any CT-ed services to be exempt so this would limit this to light commercial under 400 amps single phase or 200 amp 3-phase as these are the largest metered services we can get before our POCO requires CT metering.

I would believe that the design could be very similar to the by-pass meter bases where instead of connecting the line and load together it would just isolate the line lugs from the top meter stabs.

I'm sure that the manufactures of meter bases would jump on this requirment if they think they would make a buck, H'mmm sounds like the AFCI story

 

[kwired]

Utility vaults usually have restricted access by the customer.

Why would it have to be a utility controlled vault?

 

[Dennis Alwon]

What are the odds that a proposal gets put back after the CMP rejected it?

 

[iwire]

Why would it have to be a utility controlled vault?

If it was customer controlled we would be talking about feeders not service conductors.