If it's OK, I would like to add my comments to this thread, regarding my personal experiences in the subject of Power Engineering + Electrical Construction (applied to Commercial and Industrial Projects, as the Residential stuff I have dealt with would not include the same criteria).
First off, I am merely an Electrical Systems Designer - part of a Design/Build approach, Employed by an Electrical Contractor.
In a nutshell, I am nothing more than a glorified Draftsperson - one who compiles a Project's Design Concept into a workable reality, by performing Electrical Engineering to the system(s) and designed loads, then Drafts the compiled Engineered ideas to a Plan Set, which gets Plotted (Printed) in Hard Copy form.
Through the Engineering of the Electrical systems, I compile a set value to each and every Load, Circuit, Panelboard, Transformer, etc., which is a balance of many factors:
* Safe Installations,
* Trade-Specific / Common to the Trade,
* Adequate Capacity,
* Abilities for future loads or expansion,
* Most efficient and lowest losses, with the minimal expense possible,
* Specifically applied to the Client's needs (per specific equipment demands),
* Designed to accommodate the Client's needs, not my feelings (Engineering Ethics),
* Oriented around + related to local codes and ordinances:
Compliance applies to many codes - not just the NEC, but the California version - the CEC, per "Title 24, Part 6 Energy Conservation" codes, per Title 24, part 2 - California Building Codes, per California Mechanical, Plumbing and Fire Codes, along with Local Power Utilities Electrical Service Requirements, sometimes the Local Building Department's Planning Division, and finally - but most specifically, the AHJ and that Local Building Department's requirements for a given Project.
As I said before, I am a glorified Draftsperson that applies Electrical Power Engineering techniques to a design concept, compiles the data to related documents, then produces a visible + workable version of this stuff on hard copy documents, for use in real world applications.
Re: P.E. Certification...
The California version of the "EIT" (Engineer In Training) for Electrical Engineering Discipline, did not contain any NEC references at all.
The "Morning Section" was 4 Hours of "Everything" - all related Engineering principles, some Nuclear Physics, Ethics, etc.
The "Afternoon Section" was Discipline Specific, which was 4 Hours of Electrical Engineering calculations and figures for Power, Signal and anything else related to the field of Electrical Engineering.
The only thing related to the NEC was Ampacity Tables, Voltage Drop, and SCA.
I have not applied for the PE Exam (and I am wondering if I will do in the next 10 years!, but this is another story!),
but have heard that there is little - if any - NEC related stuff involved.
From what I know (and have witnessed many times over the past 25 years), an EIT holding "Green-EE" learns Code related stuff during their Internship with an EE Firm.
Back to my Work Experience:
My Designing experience + applications, is a very unique blend of "In-Field" Work Experience, coupled to Electrical Project Design and Engineering work.
I know of a few, and am sure there are many more Electrical Designers and EEs, whom also have come from the field into the Office, for which the same may be said of them, as well.
Being in the Field at Journeyman and Foreman level for many years, has given me the basis of code compliance, plus trade common design ideals, of which I use during every design task.
In addition to these experiences, having been involved in Management, Estimation and Consultant positions, along with working in conjunction to Communications, Data, Security, CCTV, Mechanical, Plumbing, Structural, Framing Contractors + Vendors, and Architects, has contributed to my designs.
The most basic consept is to design for ease of use and installation, for _ALL INVOLVED_
Re: Engineering Supervision:
The only time Article 310.15 (A)(1) and (C) have ever been applied (or considered) in my designs, were to address something which was _FACTORY ASSEMBLED_, and an Inspector had issues with something in that Equipment.
These issues were between the AHJ (Building Department and/or the Utility Department's Service Engineer), and the Manufacturer - I was only the one granted the lovely task of passing documents back and forth, along with hunting down the responsible personnel of design, following up on things, and all that baloney!.
For example, the most common occurrence was related to Switchgear (Service Equipment) and Factory Installed Conductors which were smaller than expected to see per Table 310.16 or 310.17.
Documentation supplied by the Manufacturer assumed liability per the design (and other disclaimers, which assured Engineered Supervision compliance per the AHJ involved), so the Equipment was finally accepted.
If I had known of the possibility for those issues prior to specifying / ordering the questionable equipment, it would have never been done! (one of those "Learn By Sample" things!).
One other issue involved an UPS Inverter, which had a HUGE label across the front stating:
"Not To Be Used On Systems Having Greater Than 5KAIC RMS SYM. Available", on a system with a listed Fault Value of 35KA at the Service, and 20KA at the UPS - and to make things even more exciting, on a Series Rated System!
The Foreman on the Project accepted the delivery of a non-spec'ed UPS Inverter (the one delivered was not the one specified in the contract documents - not even the specified manufacturer), which was the first mistake.
The Project was a Public Works job, with extreme specifications and little -if any allowed substitutions.
I was given the Project to both Manage (Project Manager) and to work as a Foreman, in order to "Put out the many, many fires lit by the previous Foreman".
The way we got the UPS to be compliant, was by installing a 60KAIR rated Circuit Breaker inside the unit, and terminate the Line Input through it.
Documentation from the Manufacturer, along with an on-site acceptance + certification by an NRTL (CSA to be exact) was required, and was sufficient for the AHJs (Building Department and the Q.C. Inspector for the Client).
These particular scenarios are some great examples of "How to work with everyone" discussions, I commonly discuss with personnel wanting to become either Forepersons, Project Managers, or Designers.
Nevertheless, I would only plan to apply Engineering Supervisions per Conductor Ampacities on something extremely specific - and believe me, just because I compiled documentation supporting it, I would _NEVER_ assume it to be anything definite - UNTIL ACCEPTED BY PLANCHECK + ACCEPTED BY THE INSPECTOR!!!
That just goes without saying!
Sorry, but I just do not have a high enough level of Testosterone, which would be required to tell a Building Department and/or Inspector to simply accept my design data, and forget everything else!
I have heard a few EEs attempting to do this, and the results were heated debates, followed by endless documentation, and eventually complying to the AHJ's NEC based requirements!
But then again, I am only speaking from the viewpoint of a glorified Draftsperson, with around 25 Years trade + Design experience, relating to Commercial and Industrial based Design/Build Projects.
One who not only creates the Plans (drafting and plotting), but submits them to Plan Check, obtains Permits, Meets with Inspectors, deals with Clients + Vendors, Subcontractors, Architects, other Engineers, General Contractors, Equipment Suppliers, Field Personnel, and related documents (faxes, "nasty-grams", E-mail status & discussions, cutsheet searching, yadda-yadda-yadda).
I can't think of anything else to add, as this message is wayyyyyy overblown right now!
Responses would be greatly appreciated!
Departing the proverbial Soapbox...
Scott35
edited after finding sum spelin airrorrs (corrected spelling)
[This message has been edited by Scott35 (edited 02-11-2007).]
