Yesterday I passed SFS6002 electrical safety course and got SFS 6002 käytännössä book. SFS 6002 electrical safety training is for all electrical work in Finland engaged in compulsory education, which must be renewed every five years. Now I know somewhat more than before on electrical safety related to electrical installations.
SFS6002 is a Finnish standard how electrical work should be performed safely. It is based on European general standard EN 50110-1 (Operation of electrical installations – Part 1: General requirements) plus Finnish national additions to it.
If you want to get your hands on the original European EN 50110-1 standard, you need to buy it. There are also free information on standard available: British edition of the standard BS EN 50110-1:2004 can be found on-line.
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Tomi Engdahl says:
Technology available today can slash the risk of grid-induced fires, reducing or eliminating the need for PG&E’s “public safety power shutoffs.”
How Tech From Australia Could Prevent California Wildfires and PG&E Blackouts
https://spectrum.ieee.org/energywise/energy/the-smarter-grid/breaking-pges-cycle-of-blackouts-and-wildfires
Equipment to slash grid-related fire risk isn’t cheap or problem-free, but could be preferable to the most commonly-advanced solutions: putting lines underground or equipping California with thousands of “microgrids” to reduce reliance on big lines. Widespread undergrounding and microgrids will be costly.
The power diverters—known as Rapid Earth Fault Current Limiters (REFCLs)—react to the surge of current unleashed when a power line strikes the ground or is struck by a tree. When this happens on one of Victoria’s 22-kilovolt distribution circuits, the REFCL instantly begins collapsing the faulted line’s voltage toward 100 volts, and can get there in as few as 40 milliseconds (ms). “If it can do it within 85 ms, you won’t get fires,” he says.
REFCLs employ a resonating coil to neutralize all but a few amps of the current in a faulty line, then use power electronics to squelch the rest.
Victoria’s 22-kV distribution circuits consist of three parallel lines. While voltage is collapsing on a faulted line, the REFCL temporarily diverts its power to the circuit’s other two lines. The customer never knows there has been a fault.
REFCL producer Swedish Neutral originally developed the device to maintain throughput in underground power lines, where faults can be hard to fully quench.
IND Technology. The hypersensitive detection system combines electromagnetic frequency sensors, which track 1-megahertz to 130-mhz signals, and algorithms that match signal patterns to the condition of the lines. With sensors placed every 4.8 kilometers on distribution lines, the system is so sensitive that it can detect vegetation within 80 millimeters of a line, and so precise that it can locate trouble spots with 10-meter accuracy.
the idea is to identify problems such as weakened lines and faulty transformers so they can be fixed before they cause sparks.
Home-grown analogs to Australia’s devices are also coming to the fore. San Diego Gas & Electric is already deploying a rapid fault detection and line shutoff system that can beat gravity, squelching current in broken distribution lines before they hit the ground.
Tomi Engdahl says:
Hurja testitulos: Valtaosassa kodin sähkölaitteista puutteita – vain joka kuudes täysin kunnossa Tukesin testissä
https://www.iltalehti.fi/asumisartikkelit/a/d0548c11-d52e-4dd8-b6d0-b708806d491d
Turvallisuus- ja kemikaalivirasto Tukes poisti viime vuonna kivijalkaliikkeistä ja verkkokaupoista 170 vaarallista sähkölaitetta.
Eniten puutteita oli latureissa, muuntajissa ja erilaisissa led-valaisimissa. Tukesin mukaan samat tuoteryhmät toistuvat vuodesta toiseen vaarallisimpien tuotteiden listalla.
–Tämä osoittaa, etteivät valmistajat ja maahantuojat aina varmista riittävän huolellisesti laitteiden turvallisuutta
Viime vuonna testatuista sähkölaitteista 41 prosenttia osoittautui siinä määrin vaarallisiksi tai puutteelliseksi, että niiden myyntiä jouduttiin rajoittamaan erilaisilla kieltopäätöksillä. Lievemmin puutteellisista tuotteista annettiin vastuuyrityksille huomautuksia, ja vain 16 prosenttia sähkölaitteista oli testatuilta osin kunnossa.
Tomi Engdahl says:
How an Australian State Fought Back Against Grid-Sparked Wildfires
https://spectrum.ieee.org/energywise/energy/the-smarter-grid/how-an-australian-state-faced-devastation-from-gridsparked-wildfires
Tomi Engdahl says:
Video Shows The Moment The Getty Fire Sparked In Los Angeles
https://www.forbes.com/sites/rachelsandler/2019/10/30/video-shows-the-moment-the-getty-fire-sparked-in-los-angeles/
Authorities have determined the cause of the Getty Fire in Los Angeles: a tree branch falling onto a power line, which officially makes the cause of the fire accidental.
Tomi Engdahl says:
Flame-Throwing Drones Are Being Used To Clean Power Lines
Whether or not this Chinese company’s idea is practical, it looks incredibly cool.
https://www.popularmechanics.com/flight/drones/a25282/flame-throwing-drones/
Tomi Engdahl says:
Mysterious Dangerous Vintage Device
https://www.youtube.com/watch?v=IMKU5S_TdHk
This dangerous mysterious vintage device is an adapter from an E27 light bulb base to a double power socket. Yes – this allows you to power any appliance (actually two) from a lamp or light. So you can load the light circuit or a table lamp with up to 2x 2kW appliances, while the light circuit is heavily overloaded, socket pins are partly exposed and the light bulb melts the appliance’s cable.
By pulling the cable, your lamp falls from a table and the light bulb breaks, starting a fire or exposing bare live electrodes.
Tomi Engdahl says:
Tiny $2 Multimeter with 1000V Range! Test with Smoke
https://www.youtube.com/watch?v=AK02JakVVPY
Testing a tiny Chinese $2.20 analog multimeter with 1000V AC / DC range. This little thing has very small probes, thin cables and loose plugs. There are tiny SMD resistors in it, about 0.6mm spacing between PCB tracks and no fuse! And this has to handle 1000V AC / DC.
Tomi Engdahl says:
$3 multimeter test & teardown
https://www.youtube.com/watch?v=R693vS09hoo
Today I test a cheap multimeter from Ebay for 3 USD including shipping (DT830B knock-off). Does this thing work? Is it safe to use? What’s inside? Let’s see in this video :).
$3 multimeter – high voltage & overcurrent test (smoke and explosion)
https://www.youtube.com/watch?v=iGUiZT6kLDk
high voltage test and overcurrent test of the 3 USD multimeter from my previous video. This video includes some smoke and explosion :). I also talked about the dangerous probes of this multimeter.
Tomi Engdahl says:
Dangerous Multimeters (+ Explosion, Smoke & Fire)
https://www.youtube.com/watch?v=AjtoIRclid8
Sharing my explosive experiences with dangerous multimeters and recreating the explosion of the probe that originally exploded inside my hand. Some multimeters can’t handle mains voltage on some ranges, despite the manual claims they should. They often claim maximal voltage to be 500 to 1000V, despite the fuse is rated only 250V. The cables have very thin copper core, despite being rated 10 or even 20A. In use, they get very hot. As the cables of the multimeter are frequently used and are exposed to bending, the copper core slowly breaks, until just few hairs remain. This mostly happens where the cable leaves the probe. Then you measure a high current (like 10A) and the cable just EXPLODES!!!
Tomi Engdahl says:
Deadly Lantern Fan – There’s 230V AC in my iPhone !!!
https://www.youtube.com/watch?v=wX5YdbyYNGk
The problem is that the circuitry is not isolated from the mains. Including the USB port. This is one of the most insanely dangerous products I’ve seen so far.
Tomi Engdahl says:
Chinese automatic house ignitor. (also available in pink)
https://www.youtube.com/watch?v=vivbspvywKo
They’re handy little desk heaters with a heating element in the form of a quartz U-tube surrounded by a metal cage. The wattages are fairly low at 200 to 300W and they give off a decent radiant heat.
These contain no safety devices at all. No tilt switch to detect if they have been knocked over, and no thermal fuse as a last resort if they are covered. As such they pose a significant fire risk unless firmly anchored down
Tomi Engdahl says:
Electrical disruptions caused by squirrels
https://en.wikipedia.org/wiki/Electrical_disruptions_caused_by_squirrels
Tomi Engdahl says:
Cable size Circuit breaker amp size How to calculate What cable
https://www.youtube.com/watch?v=KBvyX80Pdec
This video shows how to calculate cable and circuit breaker (fuse)for the design current. Bigger size cable is always better but cost much more. Hope it will help in your DIY projects.
Tomi Engdahl says:
Fail Of The Week: Thermostat Almost Causes A House Fire
https://hackaday.com/2020/01/08/fail-of-the-week-thermostat-almost-causes-a-house-fire/
Fair warning: any homeowners who have thermostats similar to the one that nearly burned down [Kerry Wong]’s house might be in store for a sleepless night or two, at least until they inspect and perhaps replace any units that are even remotely as sketchy as what he found when he did the postmortem analysis in the brief video below.
The corner-cutting of the 1980s was nothing new, of course – remember the aluminum wiring debacle? Electrical fires are no joke, and we’re glad [Kerry] was quick to locate the problem and prevent it from spreading.
Failure Mode of a Honeywell Thermostat
https://www.youtube.com/watch?v=1sCz276s_OM
In this video I took apart a failed Honeywell CT410B thermostat and analyzed its failure mode and the potential fire risk.
Tomi Engdahl says:
High voltage line inspection
https://youtu.be/9YmFHAFYwmY
Line building
https://www.facebook.com/106507614031646/posts/160845281931212/
Tomi Engdahl says:
https://www.google.com/search?q=high+voltage+line+inspection&oq=high+voltage+line+&aqs=chrome.1.69i57j0l3.10253j0j7&client=ms-android-samsung-ga-rev1&sourceid=chrome-mobile&ie=UTF-8
Tomi Engdahl says:
Insulation Resistance testing blarney
https://www.youtube.com/watch?v=0GQ4mKy8zRk
25 minutes of jabber on IR testing.
Rubber Flex Insulation Resistance Failure
https://www.youtube.com/watch?v=7p5kUMVRhYk
A short piece of flex which shows unusual behaviour when tested at 500 volts. Also includes a demonstration of cable capacitance when testing insulation resistance.
Tomi Engdahl says:
Insulation resistance and 10kV
https://www.youtube.com/watch?v=kkXCYHHtULA
Insulation resistance testing and breaking down an air gap with 10kV
Tomi Engdahl says:
Insulation resistance and RCDs
https://www.youtube.com/watch?v=s8ALrG8TU5w
Tracing the troublesome tripping of an RCD!
A closer look at how poor insulation resistance on final circuits affects an RCD, and how detecting poor insulation resistance can point you to the problem.
Tomi Engdahl says:
What’s the Difference Between Busbars and Cables?
https://www.electronicdesign.com/power-management/power-delivery/whitepaper/21120604/whats-the-difference-between-busbars-and-cables?utm_source=EG+ED+Analog+%26+Power+Source&utm_medium=email&utm_campaign=CPS200117061&o_eid=7211D2691390C9R&rdx.ident%5Bpull%5D=omeda%7C7211D2691390C9R&oly_enc_id=7211D2691390C9R
Busbars and cables have unique advantages and disadvantages. Familiarize yourself with the differences to use them properly.
Tomi Engdahl says:
https://etn.fi/index.php/13-news/10359-usb-laturit-selvasti-aiempaa-turvallisempia
Tomi Engdahl says:
Viral ‘outlet challenge’ leaves socket fried, kids in trouble at Massachusetts school
https://www.nydailynews.com/news/national/ny-outlet-challenge-massachusetts-tiktok-kids-these-days-smh-20200123-vwv2n5kcmfconkafz3gq2nmm44-story.html?outputType=amp
Tomi Engdahl says:
Can you die from testing a 9V battery on your tongue?
Vicious voltage
https://www.theregister.co.uk/2006/07/28/the_odd_body_death_by_battery/
Tomi Engdahl says:
Electrocution in Water
https://www.youtube.com/watch?v=dcrY59nGxBg
How Dangerous is it to swim in a pool when there is live wire in the water? What are the chances of
electrocution? Take a look and you may get some ideas!
Tomi Engdahl says:
How to Replace a Power Outlet
https://www.youtube.com/watch?v=on6VxMLd9HY
It is not too hard to replace a power outlet socket, if you are willing to risk it!
Tomi Engdahl says:
Electrical Lockout Tagout Equipment
https://www.youtube.com/watch?v=3fMueAINzcI
Looking at a selection of circuit breaker locking equipment and how it is used.
Tomi Engdahl says:
Building an eBay power filter kit (with schematic).
https://www.youtube.com/watch?v=uItTnwgY8Ok
This is a very common kit on eBay intended for use with audio amplifiers to filter out mains borne noise. It looks as though it’s been copied from another design, but with the usual flaws introduced during the interpretation. Particularly with regard to separation, current carrying path, pad sizing for mechanical strength and a possible swap of MOVs for class Y filter caps.
It’s quite easy to build with basic tools but will need mounted in a suitable enclosure (often the amplifier itself) with insulated pillars due to a slight design issue with live to ground clearance.
Keep in mind you can buy fully compliant inline filter modules for equipment from local electronic suppliers for professional applications.
Tomi Engdahl says:
Tiktokin hurja outlet challenge on Suomessa erityisen vaarallinen – räjähtävä pistorasia voi aiheuttaa tulipalon tai kovan sähköiskun
https://yle.fi/uutiset/3-11221080
Mobiilisovellus Tiktokissa leviää vaarallinen haaste, joka kantaa nimeä outlet challenge tai penny challenge. Haasteessa laitetaan pistoke puoliväliin pistorasiaa ja väliin jäävään aukkoon tiputetaan kolikko. Tämän seurauksena pistorasia räsähtää.
Tomi Engdahl says:
https://www.edn.com/mistakes-were-made-even-in-a-simple-3-wire-ac-hookup/?utm_source=newsletter&utm_campaign=ad&utm_medium=EDNFunFriday-20200313
Tomi Engdahl says:
Maanalainen sähköverkko vaatii tarkkuutta rakentajilta
https://www.caruna.fi/ajankohtaista/maanalainen-sahkoverkko-vaatii-tarkkuutta-rakentajilta
Tomi Engdahl says:
https://auton.fi/kaapelin-mitoitus/
Tomi Engdahl says:
Why you are so freaked on series connected extension cords?
In countries with proper electrical safety several series connected is not a big issue (although not recommended) even without any overload protection on the cords itself.
Let mains fuse to be 10A or 16A and demand extension cords to be made at least with 1.5mm2 wire and 16A rated connectors. Connect as many loads as you want, if you connect too much fuse blows before any wire starts to melt (unless tightly coiled). Demamd that extension cords with coiling mechanism that can take lots of cable to have over heating detecting breaker. Biggest issue in series connection in that plug/jack connections are not 100% reliable, more connections more risk of bad connection on some wire.
Tomi Engdahl says:
Is An Isolation Transformer A Safety Measure Or Death Trap?
https://sound-au.com/articles/iso-xfmr.htm
Use of an isolation transformer should be limited only to equipment (or test procedures) where it’s essential. The rest of the time, equipment should always be connected to the mains in the same way that it is when being used normally. While this means that there will be some parts at hazardous (mains) voltages, these are generally inaccessible in a lot of gear. The exception is switchmode supplies of course, but it’s common for them to be treated as exchange items only, and most are not designed to allow repairs.
Tomi Engdahl says:
“We used to call it the “left-hand rule” where you always used your left hand, because you needed your right hand to fill out the forms after the accident.”
Tomi Engdahl says:
Electrician exposed to 10,000 kilovolt live electric cable awarded €83,000 damages for nervous shock
https://www.independent.ie/irish-news/courts/electrician-exposed-to-10000-kilovolt-live-electric-cable-awarded-83000-damages-for-nervous-shock-39254015.html
Tomi Engdahl says:
Dangerous Device – Neon Mains Testing Screwdriver
YouTube · John Ward
Feb 8, 2014
https://youtu.be/wLAJ-keFmpk
Tomi Engdahl says:
Can you die from testing a 9V battery on your tongue?
https://www.theregister.com/2006/07/28/the_odd_body_death_by_battery/
Tomi Engdahl says:
Electrocution in Water
https://www.youtube.com/watch?v=dcrY59nGxBg
How Dangerous is it to swim in a pool when there is live wire in the water? What are the chances of electrocution? Take a look and you may get some ideas!
Inside a heated shower head. (suicide shower)
https://www.youtube.com/watch?v=cNjA0aee07k
This device is apparently quite common in countries where electrical standards are more relaxed and the climate is a bit milder. It’s basically a chunky shower head that has a heater built into it. If you do a search for suicide shower on the Internet you’ll find various pictures and videos of these things installed badly.
If you do find one of these in your travels then be very aware that there are often badly insulated mains voltage connections in the vicinity of the unit, possibly right next to a metal tap. Some have an earthing/grounding facility, but this may not be attached, or if it is it may not be electrically intact.
If you get too close to the shower head in use you may get an electric shock conducted through the water. This is made a bit more awkward by the fact these units are generally mounted quite low down.
Tomi Engdahl says:
Why do you never see birds on high-tension power lines?
https://www.edn.com/why-do-you-never-see-birds-on-high-tension-power-lines/?utm_source=newsletter&utm_campaign=link&utm_medium=EDNWeekly-20200625
We very often see flocks of birds perched in trees, on rooftops, on local power line wires, and even on radio antennas.
However, I have noticed that I never see birds coming to rest on high-tension power lines.
Tomi Engdahl says:
Mandatory Test of House Wiring. Which test is mandatory after house Wiring before connection supply?
https://m.youtube.com/watch?v=uegAr-xHCl8&feature=youtu.be
This video for mandatory Test of the house Wiring after house Wiring before give the Electricity Supply
Tomi Engdahl says:
http://www.ols-consult.fi/artikkelit.html
Tomi Engdahl says:
https://www.edn.com/why-do-you-never-see-birds-on-high-tension-power-lines/
Tomi Engdahl says:
https://www.electricaltechnology.org/2020/05/hvdc-high-voltage-direct-current.html
Tomi Engdahl says:
https://www.electricaltechnology.org/2020/06/types-of-hvdc-system-mtdc-configurations.html
Tomi Engdahl says:
https://electricalenergyworld.org/what-is-oil-circuit-breaker
Tomi Engdahl says:
https://electricalenergyworld.org/difference-between-ac-dc-transmission-line
Tomi Engdahl says:
Why I Was Almost Shocked – in Two Ways – by a Small Home AC Appliance
https://www.eetimes.com/why-i-was-almost-shocked-in-two-ways-by-a-small-home-ac-appliance/
Tomi Engdahl says:
Electrical Wiring Color Codes for AC & DC – NEC & IEC
https://www.electricaltechnology.org/2020/07/electrical-wiring-color-codes-nec-iec.html
There are multiple colors used for different wires and cables in different regions for AC (alternating current) Single-Phase , Three-Phase and DC (Direct Current) for design and installation based on the local codes, rules and regulations. Some of the well known are NEC “National Electrical Codes” followed by US and Canada while IEC “International Electrotechnical Commission” codes followed by UK, Most of the European Countries Argentina etc.
In this tutorial, we will discuss the different wiring color codes for AC (Single Phase & Three Phase), DC Power followed by NEC and IEC (Most countries (including Europe) adapted the IEC wiring color codes such as UK, China, Russia, Hong Kong, Singapore, Ukraine, Belarus, Kazakhstan, Turkey, Israel, South Africa, Argentina, Malaysia, KSA, UAE etc.) In addition, we will be showing the wiring color codes used by US, Canada, UK, EU, Australia, New Zealand, Russia, China, Japan, India, Pakistan and South Africa.
Tomi Engdahl says:
Should Stab-in Receptacle Connectors be a Home Inspection Defect?
https://icaschool.com/2017/09/27/stab-receptacle-connectors-home-inspection-defect/
They’re legal, at least in most parts of the country, but should they be? Back-wired, push-in electric receptacles were designed for one reason, and that’s convenience. If wired incorrectly, which is easier to do than you might imagine, or after years of shifting around, they can leave the home with a home inspection defect.
In your career as a certified home inspector, you’ll probably find many examples of wiring with the push-in method. Here’s why they’re not always safe, even if they’re legal.
Not All Push-in Receptacles are Created Equal
If you’ve done any residential electrical work in recent years, you’re probably familiar with receptacles that have back-wired, push-in or stab-in connectors as an option in addition to terminal screws.
Unfortunately, residential receptacles might only be designed to accept 14-gauge wire. What happens if the electrician or homeowner uses 12- or 10-gauge? Firstly, the person wiring the outlet might force the wire, which could loosen the connector clamp or break it. Secondly, if the wire does squeeze into the opening, the connection won’t be as reliable as it would with manufacturer-recommended 14-gauge wire.
Back-Wired Receptacles Make Less Contact with the Copper
Tomi Engdahl says:
AC or DC – Which One is More Dangerous And Why ?
https://www.electricaltechnology.org/2019/08/ac-dc-which-is-more-dangerous.html