220.52 A&B

[jwelectric]

These have already been sent but though I would post them here for comment.

1. Section and Paragraph:
220.52 (A)
2. Proposal Recommends:
X revised text
3. Proposal
Small Appliance Circuit Load. In each dwelling unit, the load shall be calculated at 1500 volt-amperes for each 2-wire small-appliance branch circuit ?re-qu-ir-ed- installed by 210.11(C)(1).
4. Statement of Problem and Substantiation for Proposal:
As worded it could be misunderstood that only two circuits are to be used in the service or feeder calculation due to the fact that 210.11 (C) (1) could lead one to believe that only two circuits are required by the wording ?two or more?. By changing the word required to installed it would make it clear that any and all circuits being installed as outlined by 210.11 (C)(1) would be required to be included in the service or feeder calculation.
See attached statements from inspectors and contractors from around the nation.


And


1. Section and Paragraph:
220.52 (B)
2. Proposal Recommends:
X revised text
3. Proposal
Laundry Circuit Load. A load of not less than 1500 volt-amperes shall be included for each 2-wire laundry branch circuit installed as ?re-qu-ir-ed- installed by 210.11(C)(2).
4. Statement of Problem and Substantiation for Proposal:
As worded it could be misunderstood that only one circuit is to be used in the service or feeder calculation due to the fact that 210.11 (C) (2) could lead one to believe that only one circuit is required by the wording ?at least one additional?. By changing the word required to installed it would make it clear that any and all circuits being installed as outlined by 210.11 (C)(2) would be required to be included in the service or feeder calculation.
See attached statements from inspectors and contractors from around the nation.


I attached this insert from the NEC Handbook:
Using the information found in the National Electrical Code Handbook published by the National Fire Protection Association following 220.52 (B) as outlined below I base my belief that the word ?EACH? means to include all in the service and feeder calculation.

from NEC Handbook
?In each dwelling unit, the feeder load is required to be calculated at 1500 volt-amperes for each of the two or more (2-wire) small-appliance branch circuits and at 1500 volt-amperes for each (2-wire) laundry branch circuit. Where additional small-appliance and laundry branch circuits are provided, they also are calculated at 1500 volt-amperes per circuit. These loads are permitted to be totaled and then added to the general lighting load. The demand factors in Table 220.42 can then be applied to the combined total load of the small-appliance branch circuits, the laundry branch circuit, and the general lighting from Table 220.12.?

Attached to each proposal is the following post from this site:

I copied and pasted this entire site.

 

[iwire]

Re: 220.52 A&B

I feel your proposed wording would (or could be understood as) only require two small appliance branch circuits to be included in the service calculations.

Why not go with this?

The computed load shall not be less than 1500 volt-amperes for each 2-wire small-appliance branch circuit installed.

Forget about the reference to 210.11(C)(1) as that only requires two circuits.

Remember you are trying to make it bulletproof from assaults from people like myself.

 

[luke warmwater]

Re: 220.52 A&B

To say it is 'installed by 210.11(C)(2)' implies that 210.11(C)(2) installed it. Who is 210.11(C)(2)?
So for that fact alone, I don't like the wording ,and would agree with Bob. Drop the 'by 210.11(C)(2)' part.

 

[George Stolz]

Re: 220.52 A&B

Originally posted by jwelectric:
These have already been sent but though I would post them here for comment.

Why would you send them before bringing them here? [/b][/quote]That's cool.

Maybe Charlie can give us some insight on that.

 

[peter d]

Re: 220.52 A&B

Originally posted by jwelectric:
By changing the word required to installed it would make it clear that any and all circuits being installed as outlined by 210.11 (C)(1) would be required to be included in the service or feeder calculation.

Why do we need to include more than 2 SA BC's in the feeder or service calculations?

 

[iwire]

Re: 220.52 A&B

Originally posted by peter d:
Why do we need to include more than 2 SA BC's in the feeder or service calculations?

Originally posted by georgestolz:
I flat out totally disagree with this proposal. But I will still make every attempt to help you bulletproof it before you send it off.

That is how I feel also.

 

[jwelectric]

Re: 220.52 A&B

I have heard it said many times in my 420 months of learning the electrical system that the best way to get an explanation of a section in the code is to make a proposal to have it changed.

Through all of these 8400 or so days I have been taught that any and all small appliance and laundry circuits are to be included in the service and or feeder load. Through all of these 67,200 or so hours the first time I heard a dispute to this was here in the Mike Holt Code Forum. One of the text books that I have used in my few years of teachings was published by him and even he teaches this (count one and all circuits that are installed).

It is in my heart that all that will happen with this proposal is, the fact that the wording is already clear will be reaffirmed with the comments to the proposal. Time will be the educator of one or the other of us due to this proposal. I hope that you can handle the pressure (or me if the case may be).

 

[iwire]

Re: 220.52 A&B

Mike check out this recent post at another forum from an inspector.

But, gradually we will have to change. The IRC (International Residential Code) now has us calculating all 20a appliance circuits at 1500va. Previously we only counted 2 small appliance kitchen circuits and 1 laundry circuit. (Assume only one kitchen) Under the '03 IRC if they have 5 small appliance circuits- they count all of them at 1500va. each.

NEC Demand Factor Dilemma

Wasn't the IRC largely based on the NEC?

 

[peter d]

Re: 220.52 A&B

When evaluating code rules, and changes to code rules, the one and only one question I ask myself is, "Does this rule meet the NEC's goal of insuring a safe electrical installation?"

It appears there are two separate issues here. One is the language of the code itself, and the other is the debate between those who believe the NEC only requires 2 SA BC's in the load calculations, and those who don't.

So Mike, can you really tell those that disagree with you that there is a safety hazard by using 2, and only 2 BC's, in a load calculation? How is safety in any way compromised? By insisting that all installed BC's be included in load calculations, what are you actually gaining, other than an unnecessarily large load calculation? If you can answer these quesions seriously, I will change my mind and come over to your side of the fence.

If this passes, it will be another step in the NEC becoming a design specification. I hope the CMP prevents that.

[ August 26, 2005, 11:15 PM: Message edited by: peter d ]

 

[George Stolz]

Re: 220.52 A&B

Well, I don't see this ending any different than the 15 page debacle linked above.

And since we have no effect whatsoever on the outcome of this proposal, I'm picking up my toys and going home.

 

[bphgravity]

Re: 220.52 A&B

I spoke with an engineer from Florida Power and Light a while back and got into a discussion about consumer usage and typical residential demand. The engineer claimed that they estimate at any given time during the day, the typical single family house demands less than 100-amperes of electrical service. This is supported by average energy usage statisics which are tracked by FPL. I proceeded to ask him if I were to install 4 kitchen circuits verses 2 kitchen circuits, if he would conclude demand usage would go up. He said unless the homeowner plans on using their appliances twice as much or are going to also double the number of appliances used, there would be no reason to expect higher demands by simply adding more circuits. That's what I expected to hear.

Customer energy usage
Average monthly energy usage per customer (in kwh)

Year Residential
2004 1,168
2003 1,220
2002 1,189

 

[jwelectric]

Re: 220.52 A&B

Over the past six months I have heard some good points on both sides of this debate. There have been some good analogies offered as to why these extra circuits don?t need to be added.

Let me try to use one here and see if maybe some will think a different way. If it is okay with everyone I will use the state of Florida as Florida Power and Light was used above.

Interstate 95 runs north to south and south to north through the state of Florida. In most places the speed limit is set at; let?s say 65 miles per hour. Now during the rush hour traffic the area around where Interstate 4 merges if you can hit 45 miles per hour things are moving through in fine order. At 3:00 AM when there is no traffic a person could get through there at 90 miles per hour with out much of a problem.

As you can see that the time of day would dominate the amount of speed that a person could navigate this part of the world.
At 3:00 AM when there is no traffic this part of Interstate 95 is designed where a person could navigate this section at a hundred MPH or better with out much of a problem, EXCEPT the speed is set by the law of the state of Florida at a lot less. The fact that a person COULD drive through this part of Florida has nothing to do with what the laws says.

Therefore I have sent in a proposal to clarify (for me) just what the NEC is saying as where I live it is adopted as part of our laws and anyone?s opinion would have no bearing on the law. To me it has nothing to do as weather I think it is needed or not it is only a matter of what is written in the book. As I read it as well as what every test book I can find including the NEC Handbook states that if more than two are used then all of them are to be calculated.

So now I am asking, what say ye Code Panel Two?

 

[iwire]

Re: 220.52 A&B

Mike as much as you I disagree on this issue I whole heartedly respect your sending this in to the NFPA.

We might not ever get a official interpretation of this section but you should get some sort of response to your proposal.

Bob

 

[bphgravity]

Re: 220.52 A&B

Originally posted by jwelectric:

Interstate 95 runs north to south and south to north through the state of Florida. In most places the speed limit is set at; let?s say 65 miles per hour.

Your not going to do 65 through Miami today, its under a foot of water!