General Electrical Talk Discussion http://ecmweb.com/taxonomy/term/19691/more en VFD Transformer sizing http://ecmweb.com/forums/general/general-electrical-talk-discussion/vfd-transformer-sizing <div class="node-body forum-body"><p>&nbsp;</p> <p> <span>We propose to install two 12-pulse, AC VFD drives for two 690V, 3Ph AC motors of rating 500KW each. (Total load = 1,000KW). Both the VFDs are fed by a common 3 winding phase shifting transformer. The harmonics generation may be less because of 12 pulse configuration.</span></p> <p> &nbsp;</p> </div><div class="og_rss_groups"></div><p><a href="http://ecmweb.com/forums/general/general-electrical-talk-discussion/vfd-transformer-sizing" target="_blank">read more</a></p> http://ecmweb.com/forums/general/general-electrical-talk-discussion/vfd-transformer-sizing#comments General Electrical Talk Discussion Mon, 18 Aug 2014 00:53:26 +0000 51341 at http://ecmweb.com tap conductor sizing and fusing http://ecmweb.com/forums/general/general-electrical-talk-discussion/tap-conductor-sizing-and-fusing <div class="node-body forum-body"><p>I have a question in regards to tap conductors and protection. I understand the tap conductors as per the NEC, however, I&#39;m having trouble with understanding the sizing allowed. I have a 400A distibution panel with no more fuse or breaker space available. I would like to tap its bus to feed another panel. What I need to know is what the maximum amperage is that I can tap to? For example, can I tap the bus bar and feed a 125A disconnect?<br /> Any help understanding this section of the Code would be greatly appreciated.</p> </div><div class="og_rss_groups"></div> http://ecmweb.com/forums/general/general-electrical-talk-discussion/tap-conductor-sizing-and-fusing#comments General Electrical Talk Discussion Sun, 22 Jun 2014 17:37:34 +0000 48081 at http://ecmweb.com Single Phase to three phase power conversion http://ecmweb.com/forums/general/general-electrical-talk-discussion/single-phase-three-phase-power-conversion <div class="node-body forum-body"><p>Please, can anyone clarify how to arrive at the total power consumption from the below details?<br /> <span>400V, 3ph+N, total load is 17.92kW</span><br /> 230V, 1ph+N, total load is 16.06kW</p> </div><div class="og_rss_groups"></div> http://ecmweb.com/forums/general/general-electrical-talk-discussion/single-phase-three-phase-power-conversion#comments General Electrical Talk Discussion Fri, 13 Jun 2014 10:51:30 +0000 47711 at http://ecmweb.com Multi-conductor THHN one reel http://ecmweb.com/forums/general/general-electrical-talk-discussion/multi-conductor-thhn-one-reel <div class="node-body forum-body"><p>I am looking for input on using the simpull system (or equivalent). I am bidding a project to R/R a set of 480V feeders in excess of 1,000 ft and would like to know the pros and cons from fellow tradesmen.<br /> Cost v. single conductors installation?<br /> Maintenance: good/bad?<br /> Ever delt with a single failed feeder with this system?<br /> Anything else you can think of?<br /> <span>A second set of eyes on this would help greatly. Thanks in advance for the input.</span></p> </div><div class="og_rss_groups"></div> http://ecmweb.com/forums/general/general-electrical-talk-discussion/multi-conductor-thhn-one-reel#comments General Electrical Talk Discussion Sat, 07 Jun 2014 17:03:09 +0000 47381 at http://ecmweb.com cable labels at terminations and junction boxes http://ecmweb.com/forums/general/general-electrical-talk-discussion/cable-labels-terminations-and-junction-boxes <div class="node-body forum-body"><p>I&#39;m reposting this in an effort to get some feedback on whether identification labels are required at the termination points and at junction boxes where fire alarm cable is being installed.</p> </div><div class="og_rss_groups"></div><p><a href="http://ecmweb.com/forums/general/general-electrical-talk-discussion/cable-labels-terminations-and-junction-boxes" target="_blank">read more</a></p> http://ecmweb.com/forums/general/general-electrical-talk-discussion/cable-labels-terminations-and-junction-boxes#comments General Electrical Talk Discussion Fri, 06 Jun 2014 21:09:05 +0000 47371 at http://ecmweb.com plfa cable label requirements http://ecmweb.com/forums/general/general-electrical-talk-discussion/plfa-cable-label-requirements <div class="node-body forum-body"><p>The requirement of 760.10 seems pretty straight forward: label all PLFA circuits where they terminate or are installed in junction boxes. But one fire alarm contractor is telling me that its only required where it might cause confusion for other trades such as at a duct detector on a large air handler. Using the line from the NEC, &quot;in a manner that will prevent unintentional interference with the fire alarm circuits during testing and servicing,&quot; I agree it needs to be done in a manner that prevents unnecessary interference.</p> </div><div class="og_rss_groups"></div><p><a href="http://ecmweb.com/forums/general/general-electrical-talk-discussion/plfa-cable-label-requirements" target="_blank">read more</a></p> http://ecmweb.com/forums/general/general-electrical-talk-discussion/plfa-cable-label-requirements#comments General Electrical Talk Discussion Thu, 22 May 2014 20:34:47 +0000 46811 at http://ecmweb.com HFT conduit design service life http://ecmweb.com/forums/general/general-electrical-talk-discussion/hft-conduit-design-service-life <div class="node-body forum-body"><p>Hi!<br /> I am asking for help if anyone can advise the service life of the HFT conduits in exposed environment. To my understanding HFT conduits use inhibitors for sunlight radiation protection and is suitable for 5-10 years service life. I am not sure whether the quoted service life is under direct sunlight or not. The project I am working on requires a design life of 15 years. The application for the use of the proposed HFT conduit run is not in direct sunlight, but under the eave of a building. Just wonder if the use of HFT conduit is able to meet the 15 years requirement.</p> </div><div class="og_rss_groups"></div><p><a href="http://ecmweb.com/forums/general/general-electrical-talk-discussion/hft-conduit-design-service-life" target="_blank">read more</a></p> http://ecmweb.com/forums/general/general-electrical-talk-discussion/hft-conduit-design-service-life#comments General Electrical Talk Discussion Wed, 14 May 2014 05:03:42 +0000 46061 at http://ecmweb.com Worker Dies at Oil Sands Development After Earning Electrician License http://ecmweb.com/forums/general/general-electrical-talk-discussion/worker-dies-oil-sands-development-after-earning-el <div class="node-body forum-body"><div class="node-body article-body"> <p>A worker died at the Suncor oil sands development in Alberta, Canada, this week after just earning his electrician&#39;s ticket. Shane Daye, 27, was killed while working near electrical panels on the site.</p> <p>Suncor is a sustainable energy company that recovers bitumen form oil sands through its mining and in situ operations. The bitumen from both operations is then upgraded to refinery-ready feedstock and diesel fuel. The oil sands development is near Fort McMurray, where Daye had grown up.</p></div></div><div class="og_rss_groups"></div><p><a href="http://ecmweb.com/forums/general/general-electrical-talk-discussion/worker-dies-oil-sands-development-after-earning-el" target="_blank">read more</a></p> http://ecmweb.com/forums/general/general-electrical-talk-discussion/worker-dies-oil-sands-development-after-earning-el#comments General Electrical Talk Discussion Mon, 28 Apr 2014 13:55:12 +0000 45401 at http://ecmweb.com Test your electrical smarts! http://ecmweb.com/forums/general/general-electrical-talk-discussion/test-your-electrical-smarts <div class="node-body forum-body"><p>Year the term &ldquo;electricity&rdquo; was first coined:</p> <p>A. 1600<br /> B. 1773<br /> C. 1901<br /> D. 1872</p> <p>&nbsp;</p> <p>Post your guess below!</p> </div><div class="og_rss_groups"></div> http://ecmweb.com/forums/general/general-electrical-talk-discussion/test-your-electrical-smarts#comments General Electrical Talk Discussion Mon, 28 Apr 2014 13:46:06 +0000 45391 at http://ecmweb.com Announcing EC&M's 2014 Top 10 Electrical Design Firms http://ecmweb.com/forums/general/general-electrical-talk-discussion/announcing-ecms-2014-top-10-electrical-design-firm <div class="node-body forum-body"><p>It&#39;s that time of year again -- when <em>EC&amp;M</em> unveils the highly anticipated Top 40 electrical design firms in the country, ranked specifically by electrical design revenue. Although we&#39;ve been presenting this list and comprehensive article for more than a decade, this year we wanted to highlight some additional information on the top-ranking firms. This <a href="http://ecmweb.com/design/announcing-ecms-2014-top-10-electrical-design-firms" target="_blank">photo gallery</a> offers a sneak peek at the companies making it into the Top 10 spots, listed in descending order.</p></div><div class="og_rss_groups"></div><p><a href="http://ecmweb.com/forums/general/general-electrical-talk-discussion/announcing-ecms-2014-top-10-electrical-design-firm" target="_blank">read more</a></p> http://ecmweb.com/forums/general/general-electrical-talk-discussion/announcing-ecms-2014-top-10-electrical-design-firm#comments General Electrical Talk Discussion Wed, 23 Apr 2014 18:40:33 +0000 45181 at http://ecmweb.com