Electrical Fire 6.3

A leading cause of electrical fires is loose conductor terminations to electrical equipment. Take a moment to watch as Mike and a panel of Industry experts discuss the dangers of a loose electrical termination can have and what you can do about it.
Want to learn more about this topic? This video clip is extracted from Mike Holt's Understanding Electrical Theory Library, click here www.mikeholt.c... to see the full program.
For almost 50 years Mike Holt Enterprises has been creating quality products that help electrical professionals master their craft. Our products help electricians understand the National Electrical Code requirements needed for safe electrical installations, learn the skills needed to confidently pass electrical exams, and gain the technical knowledge that will take their careers to the next level. We would be honored to help you with your studies. Visit www.MikeHolt.com for exam preparation tips and training, instructor and curriculum support, continuing education options and much more. Need additional help? Call us at 888.632.2633.

[@jlopez97122]

I believe our biggest enemies in electrical work are loose terminations, heat, and arcing which all boils down to toqrquing new installations to spec! Make sure you know how to do it and how to identify the specs on any given piece of equipment you are installing. Also for the newer apprentices, I highly recommend going to a torque and clean if your company does them. It's a perfect chance to learn how to use different torquing tools and how to identify torque values in main lugs, breakers, and any other type of termination.

[@mahadihasan93]

Tightening torques are now a days mentioned by the manufacturer. There are very good tools in the market for tightening according to required torque.

[@aurorian1634]

This clip captured an excellent discussion on electrical fires. Many reminders flooded my thoughts of my past installations. As factory electrician, I have yet to follow the torque requirements that are now written in new component manuals. I do get direct feedback from installers of our manufactured Boilers. Some techs say they hand- tight every terminal before startup. I will rummage your archives for fires with smart meters since I have had my mother's house burned down with unknown cause. I have pictures of the conductor's jacket burnt off all the way to the street transformer, under ground. I noticed a lot of censorship on this concern. I may bring this up in one of your live stream Q and A. Thanks guys.

[@trespire]

Who would be censoring this information, the smart meter installer contractor / utilities company ?

[@aurorian1634]

You can call me a tin foil hatter but I have read alternative news articles that say reports of these causing fires are ignored. It just happens that PG&E is the same company Erin Brocovich sued for cancer claims. My theory is that had the meter been an old style resistor-type, the utility surge would not continually burn the new electronics resin causing the combustion of the canopy. These new digital meters have brought a new danger that was not addressed during public discovery. I may propose a building code change that requires meter boxes a further clearance from combustibles. So far I am only sharing my thoughts here.

[@trespire]

@@aurorian1634 I'm not in the States so I had to look up who PG&E are. Seems to me like a nightmare recipy. Not only are they a private company with stock holders to please, they have public stock so are exposed to the whimsical whimes of public perception. To boost, as a utilities company, I may presume PG&E leaver the benifits of a near monopoly. I will hang my tin hat foil beside yours, in stating I have no doubt they have corrupt bad players within their ranks, and wouldn't hesitate to supress information. As customers can not install anything before the meter, including surge protectors, and the meter is not the customers property or resposibility, it should be located at the propertys edge, or in an enclosure seperate from the building.

[@aurorian1634]

@@trespire Well said, friend. I would wish to see the ugliest looking safety barriers around all smart meters. Maybe then the general public will ask why this fire-hazard was ignored during the mass change-over.

[@garbo8962]

Years ago I worked at a busy newspaper that decided to have a company come in and perform IR scan on service and panels in a 10 year old building. I was the only person that objected to them performing it starting 5 AM on a 50 degree Sunday morning when only load was some lightning. Told them it should be done after everything was running awhile.

[@TimPerfetto]

Good discussion thank you for sharing

[@mathman0101]

Great content and discussion on a very very important issue so glad you brought in NFPA70B standard for electrical equipment maintenance most electricians are familiar with NFPA70E but much less with 70B the torquing insights in there is excellent and so glad you discussed it so well. Well done👏🏾

[@RobPainless]

Good stuff, Mike. Very important.

[@Sparky-ww5re]

I've seen many burned receptacles from high resistance terminations, some nearly on fire. Backstabbed connections and old technology aluminum conductors in homes from the 60s and early 70s. Space heaters are the worst offenders not only because 1500 watts pretty much maxes out the circuit, but because they tend to be used for long periods.

[@tao0ftime]

100% agree. Space heaters = service calls/fires. The high resistance termination risk could be mitigated with a low voltage cutoff switch built into the device.

[@strakspuntnet]

hi again, i’m trying to learn from us late 60’s domestic wiring with aluminum. Since alu has bigger heatexpanse rate it makes sense to cu-pigtail or prescribe how to correct use alu wires and cables. In the Netherlands i notice now a first shift from copper to alu from safe distribution domains to the more free market. And i notice our nec(nen1010(hd/iec60364)) is never updated for alu. So I would sit back and takd notice when you guys discuss all the nec details the installer should take care of not using copper but alu! i know alu is still common in the us and reliefed after the big issues in the late 60’s with the right prescribtions, but i cannot believe it major relief was because of the minor changes of the alu conductor itselfs. Alu is cheaper than copper, but any cent cheaper expanses the conductor loaded at the other metallic connection which therefore will go finally loose… and so spark.. etc for the old alu as well for the now common alu!?

[@trespire]

Some European industrial equipment manufacturers specify that all the high voltage (400vac) / high current (up to 150A) terminals to be checked using the correct torque setting.

[@samwheller]

Mr. Holt (and company), I'm an electrical intern turned drafter (yes, I know, I should go back to school). I want to be the best electrical-intern-turned-drafter. Is there an order or list of playlists you suggest to begin devouring this channel. I'm going digest ALL the videos and might just start from oldest to newest, but I'd thought I'd check in with the master(s) first.

[@strakspuntnet]

hi from Amsterdam, mike and panel, thx for sharing! how about the bigger fine wire ferrule pre-crimp shapes conflicting the shape of terminals! should one in such cases precrimp or not and crimp by ‘torque’n the terminal’?

[@kodfkdleepd2876]

Why would retorquing be a problem? If you torque a bolt and retorque it it should do nothing. If the metal has deformed due to torquing then there should be a retorque value that compensates and one could figure out how much "creep" has happened by determining the current torque. Seems like it would be safer to retorque things properly than leaving be and much less time consuming and less error prone than redoing it all.

[@tao0ftime]

Is there a torque spec for wire nuts? What percentage of electrical fires are started by loose wire nuts? Is there any kind of wire nut torque tool? To pre-twist or not to pre-twist.....

[@jeremymiley6453]

Question about old work and when you are working in an existing panel box and find several terminals that have loosened over then years. Is it ok to retighten or should you remove, cut and retorque the connections?

[@akdisney]

14-50 receptacles are great welding but EV may heat up from long power use Do not know if not torques or the blades

[@Qiktime]

Does adding an extension to the ratchet effect the torque?

[@trope5105]

Torquing is, and possible will be the last thing in the electrical industry, that will leave the installers ego, and finally be excepted and implemented throughout the industry, as sad as it is. i work mainly in the industrial field, and luckily enough for us, many of the corporations representatives and inspectors for the companies, seem to be requiring, or at the least are moving towards the supervision of the torquing of the conductors, which is one step towards proper installation, and in doing so, takes a load of us owners and installers in liabilities concerning said installs.

[@user-dr2pg8fk2i]

Find me an electrician with a torque wrench.

[@livingunderarockunderarock9963]

I use German torque specs: Goodën tight

[@johnkulpowich5260]

Our department all electricain have one

[@cetocoquinto4704]

In my country an electrician cant even afford a torque wrench but our wires are better than china...guess what country.