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#174635 02/10/08 04:17 AM
Joined: Oct 2000
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Scott35 Online Happy OP
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Subject: Commercial Installation #1
Creation date for this scenario: February 9th, 2008

*** Please refer to the topic: "Design / Install discussions", at the Electrical Theory and Applications area, for a description of this and other scenario design / installation
threads, via the following link:

Design and Installations Discussions - Main Page

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Topic of discussion:

* Commercial Electrical Installations - Existing Occupied Building, Adding Load Equipment Only - Panels, Service And Transformers Existing.

*** Scope Of Work ***

Customer wants to add:
* Three (3) 1 Horsepower 460V 3 Phase Motor Loads - indoor, non classified area,
* Two (2) 10 Horsepower 460V 3 Phase Motor Loads - indoor, non classified area,
* One (1) 25 Horsepower 460V 3 Phase Air Compressor - outdoor,
* Two (2) 2 Horsepower 208V 3 Phase Motor Loads - indoor, non classified area,
* One (1) 208V 1 Phase 6KW Load - indoor, non classified area,
* Seven (7) 120V Loads; each drawing 10 amps - indoor, non classified area,
* Ten (10) new General Purpose Receptacles.

The new indoor loads will be located no less than 150 feet from the closest available Panelboards, and at least 200 feet from the Service Equipment / Switchgear.
The Air Compressor's run is at least 300 feet from the nearest Panelboard, and over 400 feet from the Service - but is only 50 feet from where the new indoor loads are
located.

Panelboards are:
* Square D type NF (480/277) using EDB frames,
* Square D type NQOD (208/120), using QOB Bolt-On frames.

Service / Switchgear is Square D type QED, 480/277V 3 Phase 4 Wire, 800 Amps max (Service disconnect rating = 800 Amps, no GFPE).
Switchboard section has 3 available unused spaces.
Existing maximum load on service peaks out at 230 Amps non-continuously, 145 Amps continuously.

Available Fault at the Service is quoted at 30,000 Amps - and the Utility has set a 300 KVA Transformer, where this customer is the only connection to the Secondary side.
Service feeders are 4 sets of 750 MCM Aluminum. Total distance - Transformer to Service: 50 Feet.

Closest existing Panelboards and Transformer to the proposed loads data:
* 480/277V Panelboard is fed with #2 copper, protected by a 100/3 at the switchgear. Total available free spaces = 10 single pole positions (five on each side, ability to install one 3 pole + one 2 pole frame per side),

* 208/120V Panelboard is fed with #2 copper, contains an internal 100/3 main, and is fed from a 30 KVA Transformer, which the Primary side is fed from the 480/277V Panelboard above.
208/120V Panelboard is located no more than 5 feet from Transformer, and Transformer is 5 feet from 480V Panelboard.
Available fault current at the 208V Panelboard is less than 10,000 Amps.
This Panelboard has only 6 available free spaces - two on the left side, four on the right side.
Only 1 pole breakers may be installed on the left side, without altering existing circuitry. The right side may use one 3 pole + one 1 pole breaker, two 2 pole breakers, or all
four may be 1 pole breakers.

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Building Construction:

* Concrete Tilt-Up Building,
* Height to Building Ceiling: 20 feet from inside slab to roof sheathing,
* Roof Structural: Main supports = 10" x 36" Laminated beams ("Glu-Lams"), Perlins = 6" x 8" solid wooden beam members, Sub Perlins = 2" x 4" wooden members.
* Flame Spread Partitions installed at 40 foot intervals across ceiling space: 48" wide Gypsum board, supported by steel studs.
* Seismic restraints must be applied accordingly.

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Part 1: Preliminary tasks:

This customer has contacted you, and arranged to meet on site to discuss the proposed new load installations.

The customer wants you to suggest design options, and ultimately design the project as would best serve the customer's current and future needs.

You will be responsible for Engineering the proposed installations as needed, and to do the installation as well.

You are also responsible to verify if Plan Check is required, and to perform all the necessary tasks involved with Plan Check + obtaining the Permit (along with paying the necessary fees).

The customer requests a single quote for the work (you are the only bidder), and the scope of work definitions are what was agreed upon during the preliminary job walk.
This is covered in some detail within the proposal document, along with the appropriate exclusions.

You can use markups of 20% and 10%, and still get the job.

You are able to use an average labor price of $49.65, and still get the job.

Installation difficulty may be taken off as "Standard", and raceways will be typically EMT with Steel Compression fittings.

Motor and other load equipment termination (makeup) is done by you.

Coordination with equipment vendors + related trades is required.

Field crew persons must be Certified (hold General Electrician's Certification), and qualified (experienced + ability) to perform the installations on this project.

Customer has an established Safety Program, which must be observed by anyone on the premises.

Customer requested an As-Built markup plan - in CAD format, to be submitted at project completion. The customer has the most recent version of the Project's "Base Templates" (AKA "Backgrounds"), and gives to you on a CD-R.
As-Builts to be submitted as follows:
* 2 sets of Blackline Prints - on 30" x 42" Bond Media (ARCH E),
* 1 copy of the CAD files on CD-R, saved as AutoCAD 2004 version .DWG files,
* 1 copy of the AutoCAD set, saved in .PDF format (for use by people that do not have CAD)

As-Builts to contain:
* Floor Plan(s) showing new circuitry, connections and circuit numbers / panelboard names,
* Panelboard Schedules for Panels used for new circuits,
* Details of special installations or items.

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Discussion Time:

Let's get some ideas of what to propose for installations, along with all the administrative, estimation, code compliance and other task areas involved.

I will check back later to see the progress, and add some ideas.

Scott

Last edited by Scott35; 02/10/08 04:40 AM. Reason: fixed a few paragraphs format

Scott " 35 " Thompson
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Joined: Jan 2005
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Fantasy project? Steady customer? Repeat business? Well, here's what I would do:

First of all, I'd document the bejezus out of the existing building, mapping out every utility, and tracing every circuit. Why? So it's easier next time to add to or move things ... like walls.

Second, I'd look at providing some 'infrastructure' with the job. Things like rows of strut, larger than needed (right now) trapezes, cable tray, etc.

Third, I'd invest in improving access. That mainly means providing a way to work at the ceiling level. Height apart, you often have something in the way of placing your ladder or lift ... and lift rental adds up.

Fourth, I'd make a 'workshop' or 'office' area for me ... maybe atop the office area. Speaking of which ... I'd put down permanent decking over the office area. Straddling trusses costs time.

Finally, with the distances involved, I'd use BIG pipe, with large, deep pull cans maybe every 50 ft. This is to enable you to pull additional circuits in the same pipe later.

Joined: Oct 2000
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renosteinke

Thank you for starting things out!

Great items to discuss, and I will address them each below:

Quote

First of all, I'd document the bejezus out of the existing building, mapping out every utility, and tracing every circuit. Why? So it's easier next time to add to or move things ... like walls.


Very good idea.
This documentation will make things in the future easier to contend with - and will assist in this initial project, as the Customer requests As-Builts.

We can apply these items to the proposal under "As-Builts and Record Drawings"

Since we want to get a well-rounded scenario, let's say the Building Department has requested Plans to be submitted for this Project.
We asked about this _BEFORE_ applying for the Permit, so it was not a "future surprise"

We are the Electrical Contractor doing the Installations, and Business & Professions codes allow us to perform the Electrical Design for this project - since we will be installing ("Design / Build").

Our Electrical Company has Two very experienced Electrical Engineers, which are CAD fluent, plus we have the latest version of AutoCAD and a wide format laser printer, which may print upto 36" wide media.

We propose to spend Eight Hours on site performing the actual Survey work.
Two people will do this survey.

The survey crew will identify all existing Electrical equipment - along with ratings, equipment types, free / used spaces and other relevant information.
They will also trace existing circuits via an Amprobe brand Circuit tracer, and label Circuit Directories (+ Panel Schedules) accordingly.
Along with circuit ID, they will read Amperage on feeders, heavy used circuits, and lighting circuits.

Additionally, they will identify outlets, hard wire points of connections, and building criteria - such as draft stops, framed offices, points of egress, structural data, existing conduit runs & trapezes.

Per the Utility stuff, verification and notation of size, number and type of Service Entrance Feeders, length from Transformer to Service UGPS, size of Transformer, and existing fault current.
Let's say for ease of understanding, the Utility's Transformer has nameplate information on it, and minimum SCA per service size is available in their ESR Manuals (Electrical Service Requirements).

We will say the Transformer is 13,200 V Primary Delta x 480Y/277V 3 Phase 4 Wire Wye Secondary - with a rating of 300 KVA, and an Impedance of 5.0 % Z.

The Service is rated at 800 Amps.

The Utility Company's ESR denotes a Fault Current level of 30,000 Amps at the Service Equipment, for 800 Amp, 480Y/277V 3 Phase 4 Wire Services.

All this data will be documented, then included to the Hard-Copy Plan Sets, as need be applied.


Quote

Second, I'd look at providing some 'infrastructure' with the job. Things like rows of strut, larger than needed (right now) trapezes, cable tray, etc.


Great.

We know the Customer is intent on planning for the future, so this is of high concern.

We shall install Conduit runs on the Trapeze system, so as not to exceed 50% of the maximum allowable design weight.

In other words, we build the trapezes to handle twice what we will put on them, so there will be some future capacity left over, and so the trapeze racks are not hazardous.

Per these trapeze racks, we need to brace them for seismic activity, which means "Kickers" and "Braces" mounted at given intervals.

Fortunately, our on-staff Engineers have experience for this, and the software necessary to plot out points of restraints, and the necessary materials to use.



Quote

Third, I'd invest in improving access. That mainly means providing a way to work at the ceiling level. Height apart, you often have something in the way of placing your ladder or lift ... and lift rental adds up.


We shall plan on renting at least One wide platform Scissor Lift, for the duration of the "High Work" - including the exterior and interior equipment makeup.

If Draft Stops are encountered, we will penetrate through them as described below:
* Drill holes in the Drywall (or Metal), no more than 1" larger than the size of Conduit passing through it - for sizes above 1-1/2",
* Drill hole of 1/2" larger than the conduit passing through it, for sizes 1-1/4" and less,
* Install trapeze racking on each side of the Draft Stop, within 36 inches of the partition,
* Patch or repair as necessary, any segment of the partition damaged by our Installation,
* Bring to the Customer's attention, any existing damage found during installation,
* Identify Draft Stop partitions on plans.

(BTW: Draft Stops are non combustible partitions, which are mounted at ceiling height in large open warehouse areas.
Please feel free to ask about Draft Stops if anyone does not know of them).



Quote

Fourth, I'd make a 'workshop' or 'office' area for me ... maybe atop the office area. Speaking of which ... I'd put down permanent decking over the office area. Straddling trusses costs time.


Not quite sure of what is being proposed here, maybe you could explain with details.



Quote

Finally, with the distances involved, I'd use BIG pipe, with large, deep pull cans maybe every 50 ft. This is to enable you to pull additional circuits in the same pipe later.


OK, here's a good design suggestion.

Let's all discuss the pros and cons of this approach.

For me, I would definitely go with oversized Conduit runs - along with some spare conduits, and keeping the number of Circuits to 6 maximum per run.
Of course, we may need to increase the conductor sizes for long runs, so that's an additional thought.

As to pull cans, I would suggest to place them strategically along the intended runs, in locations where they are easier to access; mounted nice and secure, and where they may eliminate a 90 - like in place of a 90.

FYI, here is some additional criteria, from the "Main Page":

Quote

Thanks for participating!

Fantasyland is a nice place to work - and one would certainly love to live there!

I chose the Project's location in Fantasyland - and the Heavenly Customer, so the discussions may be more widely accepted + easier to understand by all viewers and posters.

Having said this, let's address the items you stated:

Quote:

What about local ordinances and different adapted codes


Excellent item to post!

Being that I am in California, _MOST_ of the time, the Electrical Codes will be relevant to the CEC (California Electrical Code) - AKA Title 24, Part 3.
The "Model Code" for the CEC is the NEC.
We are currently on the 2007 CEC, Modeled from the 2005 NEC.

In Southern California, there are some local amendments, along with "listed preferences" - such as:
* Gray for 277V Grounded Neutral Conductors,
* Black, Red, Blue for 208Y/120V 3 Phase 4 Wire,
* Brown, Orange, Yellow for 480Y/277V 3 Phase 4 Wire,
* No Aluminum for sizes #2 and smaller,
* No NM Cable in Commercial installations,
* No Aluminum Grounding Electrode Conductors or Equipment Grounding Conductors.

City of LA has additional requirements.

I would like to toss around a few examples with people, and derive a fixed set of "Local Codes" to apply on our design scenarios.

My suggestions are to begin with the basics, as found in the 2005 NEC (I will include this to the first discussion thread tonight).

Quote:

Location cost factors would be an issue


Since our scenario project is located in Fantasyland, we will figure the project is somewhere on the Equator, yet still in USA.
There will be no snow, rain, wind, frost or extreme heat; and it is always the Vernal or Autumnal Equinox (12 hours daylight, 12 hours night).

Crews will commute no more than 15 miles one way, to get to the project.



Quote:

material cost is around 50% higher of the national average. With rising fuel costs, it will most certainly go up. Labor costs are 36%.


If possible, we could arrive at a National average - as determined by a consensus, or by NECA, and adjust it according to certain locations - such as yours.



Quote:

These higher averages means someone out there is running below averages which equates to more the just a few dollars different in the price.


These are exactly the things I want to discuss, as this will help shed light on the vast differences experienced across the Country.

One important note:
I plan to run takeoffs of an agreed upon (to be proposed) installation quote, through the estimating application at work, as to arrive at a given price, estimated hours, and material listing.

Would be doing that for each scenario discussion.

Prior to compiling the takeoff, everyone may contribute as to what will be included, used, paid, and such.

I would also like to draw up a few rough E sheets, and maybe some proposal documents, and add these to the thread.

Thanks for the message - hope to see you in the discussions!

Scott


We have the ball rolling now! Everyone, please toss some words in!

If you want me to begin the basic scenario, let me know. I will provide the scope and some relative details.

Thanks for contributing!!!

Scott

Last edited by Scott35; 02/14/08 06:14 AM. Reason: forgot to add SCA quote!

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
Joined: Oct 2000
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Scott35 Online Happy OP
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Post #1: Project criteria

Project design criteria has been determined, and the proposed scope of work is as follows:

  1. One new 225 Amp, 42 Space 480Y/277V 3 PH. 4 Wire Panelboard to be installed at location of new loads,
  2. New Panelboard fed with 225 Amp Feeder, derived from Service Equipment,
  3. One new 75 KVA Transformer - 480 x 208Y/120V 3PH 4W, set next to 480V Panelboard,
  4. New 225 Amp, 42 Space, 208Y/120V Panelboard with main breaker, fed from 75 KVA Transformer,
  5. New loads to be fed by these new Panelboards,
  6. New Trapeze Rack from Service to new Panels location - 24" long channel, suspended 24" below framing members,
  7. One spare 2" Conduit + Two spare 1" Conduits on Trapeze,
  8. 2" Conduit from MPOE / MDF to new area , for Comm / Data runs,
  9. Circuits and connections for new loads as listed previously.


The Proposal includes site survey and documentation labor, as well as the CAD work for the Plans for Plan Check and As-Builts.

Roof line is + 20 feet above finished floor, and the total length of run from Service to first Panelboard figures out to be 320 feet.

The new Panelboard Feeder will be protected by a 225 Amp 3 Pole Breaker in the Distribution Gear Section.
For Voltage Drop, we figure the Feeder to draw 225 Amps, and target the Voltage Drop to maximum of 2% at the Panelboard.

These items will comprise Post #2 - as described below:

I will compile a proposal, which includes all the previously listed scope items, and post it here later.
This will include the proposed scope of work items, exclusions, and such, as would be listed on a typical proposal document.

Along with this, the estimation take-off summary items will be posted.
This will include such items as Materials, estimated hours, non-productive labor, misc. items, rentals, and other items which do not get listed on the bid quote document.

With the posting of the bid documents, the Customer will accept the proposal, sign it + give a P.O. number, and send back - ready to begin work.
This will be described in light detail as an additional posted message (Post #3).

The next step will be Post #4, and will address the Plans + Building Department tasks.

Post #5 will deal with the actual installations, and may run across additional Posts. If necessary, these will be listed as "Post #5a", "5b", "5c" etc.

Post #6 will cover Inspections, billing, and other mid to near end project items.

Post #7 will cover Closeout and final commissioning stuff.

Post #8 will deal with As-Builts and other records items, as well as final Inspections and related Customer items.

Post #9 will cover files completion, job closing, and Project Manager reviews (profit/loss)

Let me know if there are any questions or comments.

Scott

Last edited by Scott35; 02/19/08 06:08 AM. Reason: revised some paragraphs for clarity

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

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