I have said it many times but the silliest thing in the NEC process is the 3 year code cycle. By the time half of the country adopts a release of the codes proposals are closed, comments are closed and the new release is at the printer. We are writing a new code without ever test driving the old one. We were just told Florida will adopt the 2011 NEC as part of the 2013 Florida building code in March of 2014.
Of course you are also buying all of the various code documents every 3 years and having to pay for update classes and all of the other burdens that brings to the trade.
I think that money stream is the main reason NFPA does it. "Codes" has become a big business.
Stretching that cycle out to at least 6 years and maybe even 10 years would make a whole lot more sense. Bureaucrats who feel they need something new to do on a regular basis would still have TIAs to evaluate and adopt.
I also think no new equipment should be added to the code as a requirement until it has actually been functioning in the field for a while. They already make accommodations for new listed products as something that is allowed but not required. Let the market drive the desire to buy these things, not a government gun.
The CEC is the same way but it isn't just about the money. By the time they get a book to the printer, it's already 3 years out of date.
Decisions made by a large committee take an incredible amount of time. Everyone has a comment, a comment on everyone else's comment, and a response to everyone's comments about their own comments. About 10 years ago I got on a mailing list for a proposed change to the CEC. They took a year to decide to do nothing, and I thought that doing nothing was better than some things that were discussed.
The CEC has a section for interpretations for the previous code book. We need to get our new code books just to learn what we should have been doing for the last three years.
I would like to see Article 450 addressed more completely - in particular, more details for Isolated Transformers of 600VAC and less (Section 450.3).
One Specific Design Issue:
Dry-Type Transformers re-energizing, due to Utility Outage (i.e.: Drunk Driver hitting Primary Distribution Pole; Affected Primary Circuit isolated, Power restored).
Primary Inrush Current Levels (involving mainly KVAR) will average the following:
25x rated Primary FLA for 0.01 Second,
12x rated Primary FLA for 0.1 Second,
3x rated Primary FLA for 10.0 Seconds.
With most of the Transformers / SDS's in my typical Projects, the SDS will be a 4 Wire System; OCPDs will be placed on both sides (Primary OCPD and Secondary OCPD).
Secondary OCP will be set at 1.25 x the Secondary FLA for the Transformer; and the Secondary Conductors are sized to conform to the Secondary OCPD rating.
On the Primary side, the OCPD will be set anywhere from 1.75 to 2.50 x the Primary rated FLA. This helps reduce Non-Selective Coordinated Primary Trip issues for Inrush and Secondary Faults.
If the Primary Feeders were allowed to be sized per the Primary FLA - instead of the OCPD, this would assist in reducing the Inrush level without increasing the length of the Feeders.
The Primary Feeders would be limited by the Maximum value found on the Secondary side - as the total load allowed would equal up to the rated Secondary FLA per the Transformer's rated KVA. For Designs where Two Panelboards are fed from a Single Transformer, the combined OCPDs equal no more than 1.25 X the rated Secondary FLA.
The concept is similar to Article 430 - allowing for the Temporary Over Currents of Motor Starting.
In the past, I have Designed some Projects around this idea - with Approval by the local DBS (Plans Examiners plus Electrical Inspectors).
Last edited by Scott35; 04/06/1301:02 AM. Reason: typical spelling blunders!
Scott " 35 " Thompson Just Say NO To Green Eggs And Ham!
I have said it many times but the silliest thing in the NEC process is the 3 year code cycle.
That's a great one, something that has always rubbed me the wrong way.
My main rant... WHY do they "think" it needs to be updated so often? It's not like it's encyclopedic content where there's large amounts of new information in each consecutive edition. Why not take, say, 5 or even 10 years for a code cycle?
There's also something to be said about the history of electrical "code" in general, too. It has become much more strict and "safety-fied" in the last ~40 years than it had been from the first edition in 1897 to the 1970's...
Polarized prong plugs weren't a "commodity" until the 80s... appliances had largely been without them for more than 75 years. It just makes you WONDER how much of new code is legitimate improvements and how much is "just because we can".