Posts Tagged ‘benchmark test’

Fault Levels Calculation Workflow and Time Comparison

Wednesday, April 4th, 2012

DraftLogic Electrical Versus Traditional Methods

Calculating fault currents for a transformer circuit

Situation description:

Project has 10 dry type transformers feeding panels. System voltage is 347/600 as service entry, transformers are feeding a variety of panel loads at 120/208 volts and one 277/480 volt panel. All panels and transformers are in a plant like building environment so sizes, locations and feeder sizes and lengths are varied.

Panels and transformers are located on the drawings and the designer has been requested to calculate fault levels at the panels downstream of each transformer to ensure that the appropriate breakers are selected for this project. Loads have been assigned to each panel but feeders and transformers have not been sized.

Using traditional methods where a designer is using an on line app to check voltage drop and some form of calculation spreadsheet to assist with the fault level calculations here is an analysis of the tasks and estimated time needed.

Typical workflow using traditional methods

1. Size transformers based on panel loads (loads are known). Estimated time 15 minutes

2. Size 20 feeders from code tables. Estimated time 45 minutes

3. Scale length of each feeder (20 ) on the drawings and check voltage drop based on expected load and selected conductor. Estimated time 40 minutes

4. Change conductor size if needed to satisfy voltage drop tolerance. Estimated time 15 minutes

5. Use fault level spread sheet to calculate fault levels for each component of each feeder, typically this will require calculation of three segments per feeder, the section from the transformer feeder breaker or fuse to the transformer, the transformer let though and finally the last segment from the transformer to the downstream panel. An estimated 70 combined mouse clicks and key strokes per transformer circuit. For 10 such circuits an estimated 700 keystrokes mouse clicks and keystrokes needed (each one an opportunity for error). Estimated time at only 10 seconds average per entry = 116 minutes

6. Collate results and prepare report for review. Estimated time 10 minutes.
Summary; Many steps needed, extensive human input for each step resulting in many opportunities for errors to creep into the process. Estimated total cycle time 241 minutes or 4 hours.

If a change is needed because of load variations the whole or part of the process must be repeated.

Same task using DraftLogic Electrical

Assumes panels were placed on the drawing using DraftLogic Electrical software which will automatically draw the single line and calculate all loads, conductor sizes based on voltage drop settings and will also calculate fault levels automatically at all critical points in the system from MDP to all downstream devices.

1. Select “single line” from report dialogue box and click ‘ok’. Estimated time 30 seconds.

2. Wait for automation to perform all calculations, size feeders and generate fault levels. Estimated time 2 minutes.
Summary; Only two steps needed, that take a couple of minutes to execute all required calculations and prepare a report for review in the form of a completed single line diagram. Estimated total cycle time 5 minutes. Using these tools all power tree objects are dealt with not just transformer circuits, the entire power tree from MDP to all downstream devices are sized, voltage drop is calculated and feeder sizes adjusted, all lengths automatically entered with adjustment factors vertical drops and connections within panels allowed for and fault levels calculated for all objects.

If changes occur, make the adjustments to whatever parameter is altered and re-run the process.


DraftLogic Electrical vastly decreases the time taken to do this task the first time around, taking only a few minutes versus four hours for the traditional method!

Not only does DraftLogic Electrical provide this incredible productivity gain, it also minimizes the opportunity for error. As you can guess from the number of manual actions and calculations being made in the traditional method, it is highly likely that errors will creep in to the manual process.

Lastly, these gains in productivity and accuracy only multiply as the work needs to be done over and over to accommodate for change requests and ‘what if’ design scenarios.

Gerry Stebnicki, President
DraftLogic Inc.
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Productivity Shoot-Out: DraftLogic Electrical vs. AutoCAD vs. Revit MEP

Monday, November 14th, 2011

In speaking with electrical engineering companies and design build companies about DraftLogic Electrical, we are asked time and time again about whether there is a version of DraftLogic Electrical that runs within Revit.


Just Like Your Dentist: You Have to Go There From Time to Time but it Always Hurts

The vast majority of those who are asking are not doing so because they like designing in Revit, they are asking because they are forced to work in Revit on certain projects. Without fail, those same folks tell us that working in Revit is costing them design productivity…and not just a little bit! Their estimate of the electrical design productivity drop is 30-40%, no small thing in a world where we need to become more productive rather than less.

All of the electrical design firms we have spoken with about Revit have experienced the same thing. The industry is forcing us all in that direction and we are developing strategies to help us still be productive, profitable and at the same time give the clients the deliverables they are requesting.


Productivity Shoot-Out to See What the Affect Is

Since we were curious about exactly how much productivity was being lost, we decided to run a productivity shoot-out. The same project would be designed in AutoCAD with the typical ‘corporate tools’ to help out, Revit MEP, and DraftLogic Electrical (which runs on top of AutoCAD).

We had some interesting results.

Here is the summary of the “production hours for the design and drawings” on this example of a multi-use 26,000 sq. ft. two story building. Production times were from experienced software users in all three production time records. The results will vary from project to project depending on size and complexity, this is just one typical example, but reflects what we are hearing from clients across North America on productivity. Producing design and drawings in 3D takes longer, always.


Design Time Required to Complete the Project

Standard ACAD = 130 hours

Revit MEP= 177 hours (a 36% increase in production cost!)

DraftLogic Electrical = 21 hours ( an 84% increase in productivity over ACAD and 88% increase over Revit)

DraftLogic Electrical with Revit output of devices only (estimated) = 37hours (net 79% increase in productivity for 2D, 3D combined output over full 3D)

This clearly outlines the potential gains by keeping the 2D elements in the 2D environment from a production standpoint. Even when doing the design in DraftLogic Electrical and then going into Revit to place the devices therein to meet the project’s Revit deliverable requirement, DraftLogic Electrical is still almost five times faster than doing everything just in Revit!


Is your goal to slavishly work in a single platform that you would not work in if you had the choice?  We don’t think so!

As designers, the goal is to get the job done with the utmost of professionalism and in reasonable time–you want a good design on a timely basis, the software you use is just a tool to get you to a completed design.

As electrical engineering firm & design build firm executives & owners, you want the work done accurately, error free, to meet client requirements, and at lowest reasonable cost to your company.  If this means that there is some deliverable in some format (a Revit model, for example), well that is just part of the job and doesn’t necessarily mean that you want or need to do the job completely in that format.

This productivity shoot-out has clearly demonstrated, as have all our benchmark tests, that DraftLogic Electrical drastically increases design productivity.  In this case, DraftLogic Electrical still vastly accelerates productivity even when one of the project deliverables involves looking at the completed DraftLogic Electrical design in order to place required devices into a Revit building model as one of the electrical design deliverables.

Prudent and intelligent use of tools available can make a huge difference to your bottom line, call or email us to discuss your situation and we’ll discuss how DraftLogic Electrical can benefit you.

Gerry Stebnicki & Dean Whitford
DraftLogic Inc. /