Sunday, December 21, 2008

Raceway fill Calculator application

from
electrician2.com
I have started working on a new raceway fill calculator application using Visual Basic that will do all the wire insulations in NEC Chapter 9 Table 5 and cables together with auto, 60 percent, 25 percent, and a custom raceway fill percentage. This is a daunting task, but after doing a similar program in Excel in 1996, then a JavaScript calculator that is now online, the methods are quite clear, but the coding is different. This project is the winter/spring event of the year and today being the shortest day of the year with about 3 hours of sunlight makes for a great time to do this kind of thing.

Saturday, December 13, 2008

Created Visual Basic 2008 Voltage Drop application

from
electrician2.com
I finally got around to downloading Microsoft's Visual Basic express 2008 net version and created a new .exe voltage drop application. I used to program in Basic and then learned JavaScript, HTML, and some Perl, but I have to say, Visual Basic is about the neatest thing since sliced bread. It combines Basic, JavaScript and HTML features, and C# and is about the easiest programming application that I have ever used. Dang, I wished this stuff had been around when I was a kid! It also builds the executable exe file application for deployment from the Internet or from a CD with about 6 clicks of a mouse. I put a link to the vd calculator at both the electrician2.com and electriciancalculators.com sites for a free download. I am already building the full version with tabs so all the calculators can be accessed within one windows application using tabs at the top. This will include a print preview and print to printer buttons. I may even created a help menu. Since it is about 10 below with a foot of snow and dark about 20 hours a day here in North Pole visual basic programming is about the only exciting thing to do. There was a bull moose walking across the lake today with a nice rack. I filmed him from the upstairs balcony. He stopped for a while and looked a me then walked on to the bank and started feeding.

Thursday, November 27, 2008

Plastic Conduit now allowed in Class I Division 2 areas

from
electrician2.com
A new change in the 2008 NEC allows the use of plastic conduit in Class I Division 2 areas. It is at Section 501.10(B)(1)(7). There are some provisions that state PVC and RTRC conduit are only allowed when metallic conduit does not provide enough corrosion protection, the areas have restricted access by the public, and only qualified persons service the installation. I thought plastic coated rigid metal conduit that Robroy and KorKap make provided protection when corrosion is a problem. I inspected an installation where RobRoy was used where a company maintained its vehicles used for pumping acid down oil wells at Prudhoe Bay and it seemed to do the job. However, the plastics people are always trying to expand their domain. In the 1987 or 1990 NEC Metal Clad cable got approved for Class I Division I locations and that was a major blow to the people that sell their labor installing electrical systems in classified areas. Metal Clad cable often called industrial rope reduces the labor bill substantially when wiring in classified areas. But let us not fool ourselves; metal clad cable and plastic conduit are no substitutes for the real McCoy, Rigid Metal Conduit! You can’t climb and walk on metal clad cable like you can rigid conduit and after 20 to 30 years of people working in these industrial facilities the conduit or cable will be walked on, used for climbing, and in some cases for holding ladders and scaffolds . Plastic is worse. Plastic has a problem in cold climates. In 40 to 50 below zero F, plastic becomes very brittle and shatters with a minimum impact. Plastic also expands too much. For a climate with -50 degree F to plus 90 degree F temperatures an expansion joint is required for as little as 10 feet of plastic conduit. Carlon, a manufacturer of plastic conduit, boxes, and fittings said in 1993 that making a plastic product for cold temperatures was not cost effective so in cold climates we are out of luck.

Tuesday, November 25, 2008

New Article 708 Critical Operations Power Systems

High Impedance Grounded Neutral Safety Observations

from
electrician2.com


High Impedance grounded systems as covered in Section 250.36 of the 2008 NEC are common in industrial installations where continuity of service is a priority. A phase to ground fault in these systems does not take the systems down and allows the maintenance personnel time to find the anomaly and correct it. A ground fault alarm may be energized for some time before the fault is cleared. This causes a rather unusual safety hazard while the ground fault is in effect. Since the ground fault places the grounding conductors at the same potential as the phase voltage the voltage between the other phases to ground remains at the phase to phase voltage until the fault is cleared. For older systems this is an added liability to insulations that may have been fine at the phase to ground fault potential but are now subject to a greater potential. It is something like a long endurance low potential high pot test for these conductors. I have seen a 480 volt system in a ground fault status for months at a time. In harsh out of door climates where snow grows to 24 feet in depth it is was not uncommon to wait until spring to clear ground faults. Unfortunately, this very situation existed in a classified area near large crude oil storage tanks that was a Class 1 Division 1 area until a second ground fault occurred on another phase causing a phase to phase bolted fault through the equipment grounding conductor material that existed at this site. Unfortunately, during the initial build of this facility 14 miles of cable tray called rigid cable support system in the 1975 NEC was installed using cables that had no equipment grounding conductors in them. This error was made with not only the 480 volt cables but in the 5 KV and 13.8 Kv cables as well. To compensate for the error the steel metal of the cable tray and conduits were bonded to form a compensatory equipment grounding system which in the case cited here had high enough impedance to prevent the 400 overcurrent device from tripping and caused arcing, sparking and smoke that set off quite a commotion amongst safety personnel. The conclusion to this little story which is true because I was there, is to clear ground faults ASAP especially when 800,000 barrels of highly volatile crude oil is flowing through the facility.


The second safety problem can be seen in Figure 77 below. In this diagram only one high impedance resistor is used and it is at the service. A neutral connection has been made from the grounding resistor XO side to the neutral point at the standby generator. The problem is that when the generator is off line and the service is online there is a potential of phase to neutral voltage between the de-energized generator windings and neutral point to the grounding conductors. A mechanic that may think the generator is off line may well find himself severely shocked if he works on the generator without having the interconnecting neutral disconnected. It might be a good practice to install a switch on the neutral for this purpose so the generator can be serviced without having to disconnect a hot neutral from the generator neutral point. Also signs should be used to warn workers about the possible hot neutral and windings.

Friday, November 21, 2008

Comments about bonding on the supply side of services

from
electrician2.com
I have been reviewing Section 250.92 of the 2008 NEC. This is one of my favorite sections that covers bonding on the supply side of services. Services are unique in that the supply side is supplied from a utility transformer that has no secondary protection. The only protection, in most cases, are the fuses on the pole for the primary side of the transformer and these are set substantially high at 300 percent in some cases. This means that if there is a ground fault or short circuit on the supply side of the service sufficient current must be conducted to blow the primary fuses and in some cases this never happens. Of course such faults are rare and this design is practical if not practicable. Therefore the bonding on the supply side of services is the most stringent found in the NEC and does not allow the use of double locknuts or sealing locknuts to be the sole method of bonding. Bonding locknuts are acceptable if there are no concentric or eccentric knockout rings left in place. But the best bonding technique is to use a grounding bushing equipped with set screws with a properly sized bonding jumper. The UL standard that addresses the stringent test for these types of bonding fittings is UL 467. I wrote an article that references UL 467 at http://www.electrician2.com/electa1/bond.html if anyone is interested.
When the bonding requirements are delineated in classified areas in Sections 501.30, 502.30, 503.30 and for the installation of intrinsically safe systems in Section 504.60 the requirements in Section 250.92 are referenced as meeting the requirements in these areas. Now one might ask, “ Why on earth does an intrinsically safe circuit raceway require the same bonding as the supply side of service?” Section 504.60 refers to Section 250.100 that sends us right back to Section 250.92(B)(2) through 250.92(B)(4). The reason is as I found out many years ago was that when a fault occurs on a power circuit that may be in the vicinity of the Intrinsically safe circuit the fault current takes many paths and one of those paths may be the raceways used for the intrinsically safe circuits. Additionally, the bonding insures less arcing and sparking from static electricity. It should be noted that the NEC is not written to fully address static electricity or lightning either. For static electricity UL standard NFPA 77-2007 is referenced and NFPA 780-2008, for lightning is referenced in Section 504(B) Fine Print Note 3.

The bonding in a hazardous location must be installed all the way back to the source of supply although the supply may not be in the hazardous location. This requirement is often overlooked at gasoline dispenser installations when the raceways, boxes, gutters, and panelboards that are located in nonhazardous locations between the service and the dispensers are not bonded according to section 250.92. The stringent bonding used for the supply side of services is required all the way from the dispenser to the service for most installations. Since 250.92(B)(4) does not permit the use of standard locknuts or bushings as the sole means for bonding, EMT connectors with standard locknuts do not satisfy the bonding requirements of this section.

Monday, November 17, 2008

New information about Disconnects for Multiwire Branch Circuits and GFCI, AFCI, and ground fault protection

from electrician2.com
Today I went to a local electrical supply house and bought the square D handle ties for QO circuit breakers labeled QO1HT. The instructions for these handle ties state that they can only be used for two single pole circuit breakers, not three.

I am in process of upgrading the change video for this change in the 2008 NEC in Section 210.4(B) that now requires that multi-wire branch circuit have a simultaneous disconnecting means located at the origin of the circuit.

While discussing the requirements that dwelling unit 15- and 20- ampere 120 volt circuits must all be protected by either a AFCI or a GFCI, the use of handle ties with these types of single pole circuit breakers appears to be forbidden. The GFCI single pole breakers definitely cannot be used for a multiwire branch circuit, but there is no concrete rule that I can find for the AFCI circuit breaker. Using two single pole AFCI circuit breakers with a handle tie for a multi-wire branch circuit is definitely a practice that should be avoided unless there are manufacturer’s instructions that state that it is acceptable.

Another comment brought out something that should be addressed. The statement that all 15- and 20- ampere 120 volt circuits in a dwelling unit must be either AFCI or GFCI protected except for the heating cables used on roofs or permanently installed fire alarm panels needs some qualifications.

The exception for the snow melting or deicing equipment is at 210.8 (A)(3). This exception states: receptacles that are not readily accessible and are supplied by a dedicated branch circuit for electric snow-melting or deicing equipment shall be permitted to be installed in accordance with 426.28. 426.28 states: Equipment Protection. Ground-fault protection of equipment shall be provided for fixed outdoor electric deicing and snow-melting equipment, except for equipment that employs mineral-insulated, metal-sheathed cable embedded in a noncombustible medium.

Therefore this receptacle still requires ground fault protection, but in this case the ground fault protection could be a 30 ma Class B ground fault protector instead of the Class A 5 ma protection.

The other exception for burglar or fire alarms is in 210.8(5) for unfinished basements. The is exception states: A receptacle supplying only a permanently installed fire alarm or burglar alarm system shall not be required to have ground-fault circuit-interrupter protection.

Summarizing, then the only receptacle in a dwelling unit that is not required to be either AFCI or GFCI OR ground fault protected is a receptacle supplying only a permanently installed fire alarm or burglar alarm system located in an unfinished basement.

Thursday, November 13, 2008

Update in November

from electrician2.com
I finally got around to updating this blog. I am not much into blogs, but after 9 months.... I have completed some new courses for Washington satisfying the 24 hour requirement and Alaska for the sixteen hour requirement and am still waiting on the approval from Alaska for the last two courses. I am still wanting to develop a Part 2 2008 NEC Change course especially for Article 600 on signs. I also made some 2008 NEC Change videos for the top 15 significant changes and may add more later. Making videos is now easier than ever because I have at last learned how to do it without wasting a great deal of time.
I remember in 1996 when I made my first computer generated video and put it on a DVD. It took three weeks to make a 5 minute video. The hard drives weren't big enough and the maximum file size back then with Win 95 was about 2 gigabytes. Actually it is fun to do now with the 500 gigabyte hard drives and the 4 gigs of memory and the software that is available, but I wish I had a studio where I could get dressed up and do the podium teleprompter thing.
I have been getting a lot of email about people using my calculators from engineers, etc. One person asked why I don't sell them. That is a good idea, but I would have to rewrite them using something like the Visual Basic developer's kit and then market them. Now they are in JavaScript and that is not a marketable type of software since it is source code dependent with no compiler. By the way, I have two other sites: http://www.alaskavirtualtour.com/ - this is my multi-media play around site, and http://www.electriciancalculators.com/ where all my calculators are also found.
The weather in North Pole is freezing and will remain freezing until the end of April. The snow came in September and will remain until April. It stays at about minus 10 to plus 20. Later we will see 50 or 60 below for sure.

Thursday, February 21, 2008

2008 NEC Changes

from
electrician2.com
I have been working on the 2008 NEC Changes since January and have finished 70 of the 200 that I will do. I placed them in a practice test page and put a link at electrician2.com. This time I am doing the illustrations with the test questions because I think this is a better method to get people to read the changes and not just do the tests alone. I should have this course complete by April 15, 2008 if all goes well.

Monday, January 07, 2008

Removal of multimedia

from
electrician2.com
I removed the audio and flash video clips and shut down my Playstream account because the traffic was just not there. There was no commercial value in this at all and it was another 3 month/$2000 experiment that failed. Over the last 13 years I have done many such experiments in website design to find what is successful. I am content at providing continuing education for electricians, web page calculators, and maybe some journeyman test prep courses but that is about it. As a one person business there is only so much you can do. It is apparent that concentrating in the few talents I have is where I should stay and that is providing electrical computer programs and continuing education for electricians. This requires a knowledge of graphic design, web page design, JavaScript and Perl programming, and knowledge of electrical theory and the National Electrical Code. That is essentially all I have to offer and at this stage of the game that is enough.

Thursday, December 20, 2007

Microsoft new IE 8 comments

from
electrician2.com
The news is Microsoft is ready to release IE 8 that conforms to international standards and passes the Acid 2 test just like Opera. I am wondering now if all the javascript calculators that run in IE 6 and 7 will run in IE 8. I will wait and see. If necessary I will revise them to run in Netscape. I used to do this but it took about two weeks for a program that took 6 weeks to write.
I have learned there is a plugin for Firefox for the windows media player that should also run in Netscape. It is a never ending task to create late model pages.

Saturday, December 15, 2007

Netscape compatability

from
electrician2.com
Microsoft has stopped supporting Netscape plugins so the windows media player will not run in Netscape. Flash does run in both browsers. The software for windows media player comes with the windows operating system and is basically not an extra cost if you know the coding. However, the Flash software comes from Adobe who has expertly bundled their software into an expensive package making the production of Flash videos and audio juke boxes about a $1000 to $2000 investment in software plus a rather complicated learning curve. About 85 per cent of the users are using the Internet Explorer version 6 or later browsers. JavaScript programs that run in IE also are not always compatible with Netscape. These incompatibility problems are because Microsoft will not adhere to the International Standards but instead goes off on a tangent that puts competing companies out of business. Presently the company that developed the Opera Bowser, a Norwegian company, is suing Microsoft over this very issue.
Perhaps individual web pages are going to be placed in a noncompetive environment using these tactics so that service providers such as Facebook, Ning, Nexo, YouTube, Yahoo, MSN, Google, Metacafe, and AOL can control the Internet. The new Internet that is evolving is the big guys with big sites and lots of ads. What really gets me is their videos do not have a mute button for turning off the advertisements!

Sunday, November 25, 2007

Update

electrician2.com
So much has happened in my web world since the last entry. I bought the Adobe Creative 3 Production Premium suite and wow things started happening. It makes processing and making movies a reality. In 1996 I spend three weeks, yes, three weeks, making a five minute video. The rendering time was 5 hours. I turned it on, went to bed, and got up in the morning to find if my video made it through. Now that time is almost one for one, or five minutes for a five minute video. Anyway I have gotten up to speed and now can concentrate on content instead of the learning curve. Today I made the video page and inserted five flash videos into it. I am going with flash because I can get about one megabyte for one minute of video with sound and with good quality. Flash is also more flexible than windows media files and allows one to build transparent figures talking in a web page as found in the rovion.com site. I have duplicated all they can do there using off the shelf software. I do not know how this can be done with windows media or if it can be done. For an 8 hour course flash videos come to 480 megabytes which is affordable. It is my own style and I like it better than the stuff I see in so many pages. So many web developers are using boilerplates from the software they use that I think they forgot how to really develop from scratch.

Thursday, November 15, 2007

Latest news

from
electrician2.com

Time does pass quickly when you are busy. I have been doing a lot of learning about flash and making those transparent movies you see in web pages. I purchased the Adobe full package and have set up a blue screen and in process of putting those transparencies in power point slides for the 2008 NEC change course. This is a lot of work and I don't know if it is worth it, but it is now an obsession with me and I am doing it.
I started some radio transmission type broadcasts with music and code changes. I will see how they work out with the logs. I think there still is not enough bandwidth liberty for the music and will probably go with just the code changes and leave the music out.
I also have redone the electrical safety film and put it in to a flash video. The new electrical accident film was also done in flash video format and windows media format at the bottom of the page.
Weather is about 10 below zero (F) here in North Pole, Alaska with about 6 inches of snow so far. It has been a very mild winter so far.

Sunday, October 14, 2007

Latest news from your host, Gerald Newton

from
electrician2.com

After doing a lot of research I have reached the conclusion that AFCI's provide protection against electrical fires. They are relative new and tripping problems may occur, but they are incidental compared to the safety these devices provide. When installed in old wiring they have found many problems that could have caused fires.

I have started the 2008 NEC online Change course and a study of cascading style sheets or css.
CSS have been around for some time and I just haven't had time to learn them. Javascript will do many of the same things, but CSS seems to be the way to go. They provide much more control over a webpage than the plain hypertext Markup Language.
I have also done a lot of work with embedding video and sound into PowerPoint html pages using the various object tags. I would like to improve the 2008 online course by using video since most people now have high speed connections. It appears the Internet is finally ready for video. I tried this in 1997 but software, hardware, and the Internet were not ready.

Friday, September 14, 2007

Hot information about AFCI's

from
electrician2.com

This is a copy of a post from alt.engineering.electrical newsgroup:

The real problem with rushing all of this into the code is this is an evolving technology that still can't detect a series arc (the one from a loose plug, cracked wire and all of those "aluminium" problems). They already have millions of obsolete AFCIs out there mandated in the 1999 code and enforced in the 2002 code that can't detect the bad power cord they scared us with when these were first proposed. The original AFCI only detects shorts in the wall. Finding a short in a power cord is what the "combination" unit is supposed to do. None can find a loose connection or partially broken wire. Then you have a bunch of Square D units that don't work at all and have been recalled but there is no tracking on this recall so most still remain in the customer's home. The technology is so proprietary that the industry can't agree on what a tester should inject in the line to see if the product works. An arcing short that trips a Square D might not be seen by a Cutler Hammer and vice versa. It is clear this is a product that is not ready for the public yet but has been jammed down our throat by NFPA and Cutler Hammer, the inventor and who proposed in in 1997. It is being tested in our homes, by force of law and the customer is paying for it.
by
gfretwell@aol.com

Thursday, September 13, 2007

AFCI change in 2008 NEC

from
electrician2.com
I have just attended the Northwest IAEI Section meeting in Anchorage Alaska where the 2008 NEC and Analysis of Changes were taught. A new rule is requiring that all 120-volt, 15- and 20- ampere branch circuits supplying outlets installed in dwelling unit family rooms, dining rooms, living rooms, parlors, libraries, bedrooms, sunrooms, recreation rooms, closets, hallways, or similar rooms or areas shall be protected by a listed arc-fault circuit interrupter, combination-type , installed to provide protection for the branch circuit. The combination-type means that the AFCI provides series and parallel circuit protection.
Also, the AFCI provides protection from bad arcs that cause fires but does not provide GFCI protection because the ground fault tip is set at 50 ma.
Now what came up with a Code making panel member during break was does anyone make a AFCI/GFCI that provides both the 5 ma GF protection and the AFCI protection and if they do, why not just go the whole course and require both?
It turns out that Cutler Hammer does make such a device, but Square D does not.
So now what should we do? Wait for the 2011 NEC or jump the gun and put these Cutler Hammer AFCI/GFCI devices in now?

Changes that need to be made for the next 2011 NEC

from
electrician2.com
Hopefully, someone or I will get these in by November of 2008 for the 2011 NEC.

1. Motors for R/V's need to have overload protection and disconnects regardless of voltage. Presently these RV electrical systems' low voltage circuits escape the NEC by being part of the automobile electrical system. Motors used for tip outs are now burning up at a rapid rate and sometimes they take the wiring harness with them. Something needs to be done.

2. R/V manufacturers should be required to provide an electrical diagram with the R/V's. Presently they are not all doing this and it is a nightmare to try to work on these electrical systems.

3. Greenhouses. Where receptacles are used in green houses to provide power for auxiliary equipment they should be protected by a Class a GFCI. I have watched at least one worker working on a wet floor with a frayed extension cord dragging in water as they run a vacuum cleaner in a greenhouse. This needs to be addressed.

4. Cathodic Protection. Impressed current cathodic protection systems are not included in the NEC. The Canadian Electrical Code does include them. These systems are used extensively to protect oil industry tanks and pipelines. The conductors are often mistaken as grounding conductors and vice versa. Something needs to be done.

5. Natural Hot Springs. What are they and what do they become when modified with liners, pumps, and electrical lights. I know of at least one such spring that is an accident waiting to happen. We have all heard of swimming pools in Mexico and Puerto Rico electrocuting several swimmers at once. Let us hope this doesn't happen in Alaska at Chena Hot Springs.

Wednesday, September 12, 2007

from
electrician2.com

I finally attended an IAEI Northwest Section Meeting in Anchorage, Alaska after 14 years. This one was a big one and the NFPA hurried their publishing date so the 2008 NEC would be there and for sale. The IAEI also had the Analysis of Changes for sale and given out to paying attendees. We had one half day on the CFR’s and application of NEC70E for employee safe work practices and two days of NEC changes taught by excellent instructors.
Now let’s get real. The seminar cost $340 plus travel and plus housing plus lost wages. Attendees could stay at the Hilton where the seminar took place for $150 a night. That would be 5 nights or $750. Then there is travel to and from Anchorage for those that do not live there. For some that comes to about $400 unless you bring your wife. So now we are up to $340+$750+$400 or $1490. Add to this your shopping and buying a few IAEI books and we are up to about $2000. Of course if you are working add lost wages so we now have about 3 grand into a sixteen hour code class for the 2008 NEC.
This is why I embrace the Internet online learning courses. They simply are the best and the most practical for most of us.
There were several code making panel members at this meeting and that was an enlightenment. I heard such remarks from them as we didn’t have time to really work this change out so we did the best we could and put in what we had, it will need further work. I was appalled. When I think about the number of inspectors and electricians that have put their jobs on the line for this NEC rule or that, and when you learn how casual the code panel members talk about the new rules, I wonder if they realize the consequences of their actions. I for one will never take the NEC to be the ultimate word as I once did. Common sense has to be applied. I have seen inpectors make a contractor tear out and completely rlocate a panelboard over a one inch clearance violation. That is simply wrong! On big projects for big companies I have seen inspectors work relentlessly to enforce the rules in the NEC to the "T" but after a company gets into serious trouble, who do they hire to supersede and intimidate the very inspector that tried to enforce the rules, no one but a distinguished Code Making panel member who comes in for $1200 and day plus per diem and who for that price tries to put the "bad" inspectors in place. I have been there and witnessed the events. That is simply wrong too. What is needed is a code of conduct for inspectors so they learn that the NEC is approximately correct, and in every case of enforcement a practical tolerance must be applied.

Tuesday, February 13, 2007

Improvements made to Motor Circuit Calculator

I made some improvements in the checking of inputs to reply with alert messages. The maximum overcurrent device is 6000 amperes by 240.6(A) but for some larger motors this value is exceeded. I also dressed up the motor nameplate input to test for illegal variables and give alerts. While testing the outputs against the Ulgy's charts on pages 40 and 41 for three phase motors I found several errors in Ugly's. The conductor size for a 100 hp 460 volt motor should be 2/0 in place of 1/0. Also the conductor sizes in Ugly's are set for a No. 12 minimum while a No. 14 is sufficient in many cases. The small conductor size rules in 240.4(D) of the NEC do not apply to motor circuits. Also the Ugly's circuit breaker sizes do not follow the NEC rules for inverse time ciruit breakers. I do not know the rules they follow if there are any.

from
electrician2.com

Saturday, February 10, 2007

Motor circuit Calculator quality check

I have begun a thorough quality check of the motor circuit calculator. First I am checking all the NEC table entries in the program to make sure they are correct. Next I am creating an Excel Spreadsheet that duplicates many of the critical calculations. Then I plan to check the calculator against the spreadsheet. This project will take several weeks. Quality control is a major time consuming process with computer programs and is probably why so many programs require that you sign a no fault agreement before using them. Quality control and quality assurance are obiviously major expenses for large software corporations, but give the small guy an advantage. Small guys can always call it a "beta copy" and hope for the best.
from
electrician2.com

Sunday, January 14, 2007

Range Calculator now Online

It is 167K and about 4000 lines of code and appears to do the job of finding demand loads for up to 1000 ranges and more. It was a humdinger to write, but after breaking it down into doing just what the NEC does and not trying to make an all in one program it became easier. It has 9 examples taken from books, NEC, and some of my own. It is under the calculator menu or go to:
http://www.electrician2.com/calculators/rangecal_REV1.html


from
electrician2.com

Monday, January 08, 2007

Range Calculator status report

I am continuing work on this calculator. There appears to be some holes in the NEC application rules for Table 220.55. For instance, what do we do with ranges, cooktops, and ovens when they are supplied by the same feeder or service and they vary in values from about 3 KW to 27 KW of unequal ratings? This project is attempting to find the feeder or service load for up to 1000 ranges, ovens, and cooktops including any combination of these for ratings of 1 3/4 KW to 27 KW allowing up to 10 unequal ratings. The input is by mouse selections using 0.1 increment values for KW. A separate calculator is being created for branch circuits.

from
electrician2.com

Sunday, December 31, 2006

Starting another calculator for ranges

I have begun the tasks of making sense out of the rules for ranges in Section 220.55 and Table 220.55. Again, 95 per cent of the time the rules are simple, but a computer program is suppose to be able to do all the problems. For instance how about 25 each 15 kw ranges, 6 stove tops at 3 kw, 10 ovens at 5 kw and 45 ranges at 12 kw, 14 ranges at 6 kw and one range at 20 kw? Now we are talking about some lines of code.

from
electrician2.com

Monday, December 25, 2006

Bug in Online Dwelling Unit Calculator at electricalknowledge.com

I went to the electricalknowledge.com "single family dwelling Calculator" and tried it with the NEC Annex D example D1(A) and found it has an error in it. The name alone should tell a person an amateur wrote the program. It should be dwelling UNIT calculator. Anyway, for the 70 per cent calculation for the range neutral load they use 12 KW instead of the demand load of 8 KW. You would think that these people would at least try the examples to debug their programs. This tells me that they aren't good code people, but probably are programmers trying to do code programs.
Merry Christmas!
from
electrician2.com

Motor Branch Circuit Calculator

Motor Branch Circuit Calculator
Branch Circuit Conductor Sizing Calculator
Voltage Drop Calculator
Conduit Fill Calculator
Cable Tray Pulling Tension Calculator
Electrical Calculator
Ohms Law Calculator
Power Calculator
All at:
electrician2.com
under the calculator menu
or try:
Calculators

from
electrician2.com

Saturday, December 23, 2006

Thoughts about some really great electricians

I wonder where they are tonight. Duke Kennedy, Adolph Ike, Pat Harrington, and Gene Gilbert. These weren't just electricians they were giants in the trade. They were the geniuses that I have met over the years, real champion mechanics. I wish we had a club where we could meet, but it is not that way. Just like the military, we all met and did our job and then went our ways, and now they have retired in different parts of the country. I guess I miss the camaraderie, the coffee break shacks and all the bull we talked about mainly politics, sex, and unions. I am into my second month of retirement and I must say it is an adjustment. I miss working, to be honest.

Friday, December 22, 2006

A day of research

I spent the day doing research. I searched and searched at Google. I was surprised that a search for electrician.com comes up with electrician2.com. What's up with these Google guys? As a matter of fact a search for electrician does not come up with electirican.com at all! It was in the top two links for several years. Evidently, Google is on to the Click for Cash marketers and is weeding them out, since electrician.com that I sold is now a click for cash site. My search for electrician2.com now has 2600 pages and is a rising star. It should be with a $100,000 worth of online free calculators readily available. I sure wish I could have had those calculators at my disposal when I was a foreman on several jobs. I had to do all that math by hand and never knew if it was right or wrong. Nothing like being out in a remote part of Alaska in the middle of winter in the cold and blowing snow and having to figure out what size wire to use then drive to a snow banked dock and seeing if you can find it or a substitute. Those were the days, my friends, those were the days. Now the Internet is availble at almost every job shack in Alaska!

Thursday, December 21, 2006

Today is the shortest day of the year in North Pole

It was dark for most of the day and -21 degrees F. I got the Christmas and New Year’s cards online and running. Now I need to put the links in at the main page. I am listening to the music juke box at the Christmas card as I type. I sure like that Yanni guy. His music is comforting especially when it is so cold and dark out. I think the dogs like him, too. Other than that it has been a wasted day. I did absolutely nothing of value. Well not quite, the car wouldn't start this AM and I spent about an hour looking for the battery charger. So I hooked up the space heater and the battery charger and waited an hour and it started. The truck is in the repair shop because the heater fan quit two days ago. And it is only 20 below! I don't know what is going to happen if it gets 50 below. Cold weather takes a lot out of people and equipment. Day after day, cold and dark. Why I stay in this forsaken place is beyond me. Oh yes, my parents are buried here, and everyone I know in the world lives here. It is home for me; anyway it is the only home I know. I guess it is like that for lots of people. When you drive through some small town and wonder what keeps it going, I suppose just being a home is a lot of it.

Wednesday, December 20, 2006

New site for calculators

I have started a new site at http://www.electriciancalculators.com that is already the premiere site for free online electrician calculators. Why premiere? Because no one else is doing it and I was first. My simple voltage drop calculator that I wrote years ago and placed at my old site electrician.com is all over the Internet because I allowed persons to use it. Well they used it and forgot where it came from. I can look at the source code at so many sites and see that they did not even bother to change the variable names. Talk about plagiarism! After writing my article on the mathematics of the offset bend and developing a calculator using my original equations, I started getting email from the Palm guys wanting to sell me their new calculator that allows you to pre cut pipe to 1/16 of an inch and do offset bends and come out right. They practically stole my words word for word. They seem to follow me around and steal my ideas and programs. Anyway, the new site is in the works and has as an index page with a fairly detailed description of the programs and links to them. I need to get back to writing programs and checking out the motor branch circuit program more. These programs do hundreds of thousands of combinations and it takes a lot of time to gain confidence that they work right all the time. I think I will do a load calc program for a single family residence, motor compressor, transformer, RV Park, Mobile Home Park, or welder program next. I wrote an RV Park program that did the sectionalized voltage drop many years ago in MBasic. I wish Webpage calculators could be written in Mbasic, but Mbasic does not work well with forms so I guess I am stuck with JavaScript. I like JavaScript because it so portable and readily available. The Internet changes so fast that by the time you get a program out on a CD or marketed online, it is almost obsolete. The Internet is humming faster and faster and JavaScript allows me to keep up with the hum.

Thursday, December 14, 2006

electrical calculators for electricians

http://www.electrician2.com now has 24 free online electrical calculators for conduit fill, voltage drop, power, ohm's law, Table 310.16 for wire size, OCPD, and continuous and noncontinuous loads, and parallel conductors and a motor circuit calculator. 23 of these calculators are written in JavScript and one is in Excel. The 2005 NEC Code is followed with these calculators.

Wednesday, December 13, 2006

Parallel Conductor Calculator uploaded

I finished the Table 310.16 parallel conductor calculator. It is full of suprises. I also wrote another voltage drop calculator that finds the maximum distance for a given conductor size, per cent voltage drop, and load.

Sunday, December 10, 2006

Starting work on Parallel Conductor Calculator

I have begun work on a calculator that finds the amperage, OCPD, equipment grounding conductor size and voltage drop for parallel conductors No. 1/0 AWG and larger. I plan to use this calculator to build a Table for conductor sizes and OCPD's to 2000 amperes that will include the raceway sizes. Of course of even more interest is how cost effective are the different parallel configurations. I have always wanted to know which pipe and parallel configuration for a fixed load is the least expensive and would like to see a comparison chart. I may take it that far. This would require using the Means estimating book to find the labor costs, and of course the material costs vary every day with the price of copper fluctuating like it does.