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.
760 Comments
Tomi Engdahl says:
Difference Between Grounding, Earthing and Bonding
https://www.electricaltechnology.org/2020/07/difference-between-grounding-earthing-bonding.html
What is the Difference between Earthing, Grounding and Bonding?
There is unusual confusion to understand the basic concept and main difference among grounding, earthing and bonding even some professionals interchanged the word for earthing, grounding and bonding such as earthing bond, bonding ground etc. In addition, electrical bonding is a totally different thing other than grounding and earthing.
To the point, Grounding and Earthing is the same concept expressed by different terms used for them. There is a small difference between earthing and grounding which we will discuss in detail
Tomi Engdahl says:
https://www.electricaltechnology.org/2020/07/electrical-wiring-color-codes-nec-iec.html
Tomi Engdahl says:
Why are Stones laid in an Electrical Substation?
https://www.electricaltechnology.org/2020/07/stones-in-substation.html
Tomi Engdahl says:
Electrical safety
Information to help organisers and others plan, use and manage electrical equipment at an event safely.
https://www.hse.gov.uk/event-safety/electrical-safety.htm
Tomi Engdahl says:
Keeping Festival Goers Safe From Power Equipment
https://www.trinitypower.com/keeping-festival-goers-safe-power-equipment/
From the performances to the ambiance, music festivals can be electrifying. But a lot of work goes on behind the scenes to ensure that electric feeling is never the result of an encounter with electrical gear.
For a closer look at the planning involved in keeping festival goers safe from temporary power equipment, we spoke with Garett Lumley, owner of Down to the Wire — the electrical contractor behind the stages, lights and art installations of the Shambhala Music Festival.
A major concern with power cables in crowded places is the tripping hazard. “That’s probably the biggest hazard that we try to mitigate,” explains Lumley. Not only can exposed cables trip people up, but with 600 volts on site, the high voltage of the cables represents another level of risk.
That’s why Lumley buries them. “Everything’s underground,” he explains. “We’ll put a little trench in there about half a foot wide by half a foot deep, put the wires in there and then backfill it, so it looks like we were never there. And a week later, [when the festival is over], we pull them up.”
Trenches for the temporary power cables aren’t very deep — only 6 to 8 inches — but it’s enough to prevent any foot traffic from making accidental contact with the cabling.
While cables can be buried, the other power equipment — generators, transformers and stage wiring — has to be managed differently.
“All the transformers for the stages are backstage,” explains Lumley, “So that restricts most access, which is the biggest thing.”
The cables are run underground into secure areas where outdoor-rated generators and transformers await, protected from the elements and from the general public.
Tomi Engdahl says:
What’s inside a mechanical socket timer + modification
https://www.youtube.com/watch?v=arSndtfrlaU
Tomi Engdahl says:
Failed Hexagon USB Socket Extension Lead
https://www.youtube.com/watch?v=wneFtZ755wE
An extension lead with 4 outlets and 4 USB sockets. A total failure straight out of the box. Inside – more fail.
Tomi Engdahl says:
Hexagon Socket tests – USB, Current, Overheating and Flames
https://www.youtube.com/watch?v=yuZjxIEvP2A
Tomi Engdahl says:
When designing an internal #PowerSupply into a system, the #safety, thermal & #EMC implications of the installation must be considered TT Electronics #PCB #ground https://buff.ly/31dGyqh
Installation considerations for internal power supplies
https://www.edn.com/installation-considerations-for-internal-power-supplies/?utm_content=buffer61f7e&utm_medium=social&utm_source=edn_facebook&utm_campaign=buffe
AC/DC power supplies can be classified into one of two primary families: internal or external. Internal power supplies are those which will be installed within some end device as a component; external power supplies accompany an end device as a stand-alone sub-assembly. Internal and external power supplies vary greatly in the degree of engineering effort required to successfully implement the power source as an element of the final system.
When designing an internal AC/DC power supply into a system, several factors must be considered surrounding the safety, thermal, and electromagnetic compatibility (EMC) implications of the installation. This article outlines the caveats associated with utilizing an internal power conversion solution in opposition to an external one and provides guidance on achieving a proper installation.
Tomi Engdahl says:
The Revolution of Electrical Infrastructure is Starting
https://www.eetimes.com/the-revolution-of-electrical-infrastructure-is-starting/
There is plenty of opportunity to make old residential electric infrastructure more efficient. The residential represents an attractive market for companies that offer intelligent control systems.
Startup Amber Solutions has created a series of solid-state electrical control solutions for smart sockets, circuit breakers, and more, providing an intelligent control base within the electrical wiring endpoints of buildings for use by security and automation providers.
The company announced it has signed a letter of intent and six memoranda of understanding with leading global electronics manufacturers. It also announced it has completed and/or is building complete solid-state demonstration models and pre-production products across a range of categories that include intelligent multi-function capacitive dimmer touch switches, 2-wire dimmer switches, intelligent sockets, and retrofit programmable and intelligent circuit breakers Din Rail (Europe) and NEMA (United States).
“So Amber has the opportunity to directly impact this electricity space and bring real benefits and fix real problems. We are the modern architecture in the breadth of electrically powered equipment itself in the outlets where you plug into, the lighting switches, every electrical end point in buildings — even in the circuit breaker itself — to give you complete, the whole building protection with more modern, intelligent and cost-effective energy management and delivery.”
“Amber’s main innovation is a programmable solid-state power management system that uniquely controls the current flow digitally, offering integrated control intelligence — essentially our breakthrough is we control electricity, digitally,” said Casey. The solution introduces a much safer, more reliable, and significantly smarter functional alternative to the electromechanical components of the 1970s that are standard in electrical infrastructure products.
Today’s standards can still lead to electric arcs and fires. The combined intelligence to manage energy dynamically with the digital solid-state structure provides new opportunities to eliminate nuisance AFCI and GFCI trips, support flicker-less LED lights, and provide embedded surge protection in every electrical endpoint powered by Amber’s technologies
“In this case, it’s the 6,000-volt surge protection, which some of our partners want and we already have this completed. And, yet other companies that we’re talking to want to go a bit over that, for very specific reasons — like 10,000-volt surge protection, for example. So we are working on that now. And, because we can dynamically manage electricity, 10,000 volts is not a problem. Our technology supports a wide range of such requirements. Do we need 10,000 everywhere? I don’t know. But at the end of the day, we can fully support market requirements like this and that’s one of the reasons we are getting so much interest from all of these major companies. We can support the specific requirements that they feel are important, competitive and disruptive” said Casey.
Amber’s solid-state solutions are compatible with a wide range of existing automation and control systems and can disconnect live power up to 3,000 times faster than a physical switch can trigger. “By managing electric without moving parts, the risk of fire is dramatically reduced — practically eliminated, as there is no possibility of an electric arc (common with power switches and light switches),” said Casey.
He added, “We can actually be 3,000 times faster than a typical breaker. Why? Because it’s solid-state, and we control the AC switching digitally. Therefore, we can sample and test on the first cycle of the sine wave and determined if this was an arc. And then we can wait. We can wait at zero crossings, and then we can see if that’s going to repeat itself or not. And then if it repeats itself, it’s an arc, we will make a decision to shut it off.”
Tomi Engdahl says:
https://en.wikipedia.org/wiki/Distribution_transformer
Tomi Engdahl says:
When designing an internal #PowerSupply into a system, the #safety, thermal & #EMC implications of the installation must be considered TT Electronics #PCB #ground https://buff.ly/31dGyqh
Tomi Engdahl says:
https://www.electricaltechnology.org/2020/08/electrical-power.html
Tomi Engdahl says:
Photos of Hanoi Power Transmission Company cleaning live-line porcelains with high-pressure water
https://en.evn.com.vn/d6/news/Photos-of-Hanoi-Power-Transmission-Company-cleaning-live-line-porcelains-with-high-pressure-water-66-163-1628.aspx
This method makes it easy to clean the devices on the grid without power outage, reducing the discharge incidents due to contamination, improving the reliability of power supply to customers, especially during the up-coming hot season of 2019. Photos taken by evn.com.vn at Kim Dong 220kV Substation (Hung Yen province), 6 March 2019.
Tomi Engdahl says:
https://www.electricaltechnology.org/2020/08/what-is-electricity.html
Tomi Engdahl says:
https://favouritehub.blogspot.com/2020/08/electrical-power-system-types-sources.html
Tomi Engdahl says:
https://www.electricaltechnology.org/2020/08/difference-single-phase-three-phase.html
Tomi Engdahl says:
https://www.asc.ohio-state.edu/physics/p616/safety/more_current.html#:~:text=A.C.%20is%20More%20Dangerous%20than,which%20lowers%20the%20skin%20resistance.&text=The%20frequency%20of%20the%20AC,effect%20on%20the%20human%20body.
More about “The Fatal Current”
Electric current damages the body in three ways:
harms or interferes with proper functioning of the nervous system and heart
subjects the body to intense heat, causing burns
causes the muscles to contract
Remember, it’s the Current that Kills!
It’s the electrical current that does the damage. Current equals voltage divided by resistance (I = V/R), but voltage is not a reliable indication of danger because the body’s resistance varies so widely that it is impossible to predict how much current will flow through the body for a given voltage.
The actual resistance of the body varies depending upon the condition of the skin (moist or dry) at the points of contact . The skin resistance may vary from 1000 ohms for wet skin to over 500,000 ohms for dry skin. However, once the skin is broken through (for example, by the burning away of skin or by a wire piercing the skin) the body presents no more than 500 ohms resistance to the current.
Tomi Engdahl says:
A.C. is More Dangerous than D.C.
A.C. is said to be four to five times more dangerous than D.C. For one thing, A.C. causes more severe muscular contractions. For another, it stimulates sweating, which lowers the skin resistance. Along those lines, it is important to note that resistance goes down rapidly with continued contact. The sweating and the burning away of the skin oils and even the skin itself account for this. That is why it’s extremely important to free the victim from contact with the current as quickly as possible (but without endangering yourself) before the climbing current reaches the fibrillation-inducing level.
The frequency of the AC has a lot to do with the effect on the human body. Unfortunately, 60 cycles is in the most harmful range. At this frequency, as little as 25 volts can kill.
https://www.asc.ohio-state.edu/physics/p616/safety/more_current.html#:~:text=A.C.%20is%20More%20Dangerous%20than,which%20lowers%20the%20skin%20resistance.&text=The%20frequency%20of%20the%20AC,effect%20on%20the%20human%20body.
Tomi Engdahl says:
First Aid Treatment in Electric Shock – Causes, Sources, Severity
https://electricalfundablog.com/first-aid-treatment-in-electric-shock/
Tomi Engdahl says:
China’s MILLION VOLT Energy Superhighway
https://m.youtube.com/watch?feature=share&v=rThkjp-bp8M
Smart grids delivering renewable energy across continents will be a crucial advance, but they will also require extremely long electricity transmission distances. Our existing power lines are becoming more and more inefficient as those distances grow. China is tackling the issue by switching from AC to DC power and ramping up the output to a truly eye-watering 1.1 million volts. An environmental breakthrough or a bid for global energy domination?
Tomi Engdahl says:
Thick, black ribbed overhead power lines. Including ABC termination.
https://www.youtube.com/watch?v=8JFfXZt7QoI
If you’ve ever seen overhead lines and wondered what they look like up close then here’s your chance without being electrocuted in the process.
In this video I look at bare overhead copper wires and their spacers and also the new ABC Aerial Bundled Cable/Conductor lines.
Tomi Engdahl says:
Ten Car Battery Presentation at Calgary Mini Maker Faire
https://www.youtube.com/watch?v=ZxBF7WC0TQk
first presentation in front of live audience!
covered:
- Which one hurts more, AC or DC?
- What kills, current or voltage?
- Can we weld with car batteries?
Tomi Engdahl says:
https://electricalfundablog.com/equipment-earthing-works-types-applications/
Tomi Engdahl says:
https://www.electricaltechnology.org/2020/09/difference-single-phase-three-phase-induction-motor.html
Tomi Engdahl says:
Electrical safety testing
https://en.wikipedia.org/wiki/Electrical_safety_testing
Tomi Engdahl says:
Electrical Safety Tests
https://www.ebme.co.uk/articles/electrical-safety/electrical-safety-tests
Tomi Engdahl says:
Myrsky voi aiheuttaa jopa hengenvaarallisen nollavian – näin tunnistat sen
https://www.iltalehti.fi/kotimaa/a/1628447a-e304-46f6-95dc-3e9786875eb6
Sähköverkkojen vaurioituessa voi esiintyä hengenvaarallinen nollavika.
Nollavika ilmenee, jos nollajohdin katkeaa. Tämä voi pahimmillaan aiheuttaa jännitteen nousun, joka voi rikkoa kodin sähkölaitteita sekä saattaa aiheuttaa sähköisku- ja tulipalovaaran.
– Nollavika voi aiheuttaa sähköiskun vaaran etenkin piensähkölaitteissa, kuten latureissa tai laitteissa, joissa on jo valmiiksi heikkous
Näin tunnistat
Jarmo Ström kertoo, että nollavian voi havaita monin eri tavoin.
– Nollavian näkee selkeästi hehkulampuista valojen toistuvana himmenemisenä ja kirkastumisena. Uuden tyyppisissä valaisimissa on vaikea huomata himmenemistä. Valojen voimakkuus vaihtelee etenkin muiden sähkölaitteiden käynnistyessä tai sammuessa.
–Toisaalta sähkölaitteiden, esimerkiksi jääkaapin kummallinen toiminta voi olla myös merkki nollaviasta, hän sanoo.
Strömin mukaan nollavikaa voi esiintyä etenkin rakennuksissa, joissa ei ole rakennuskohtaista maadoitusta.
– Jos talossa ei ole maadoitusta, nollavian näkee selkeämmin. Uusissa kiinteistöissä se on harvinaisempaa.
Hänellä on selkeät ohjeet siihen, miten kannattaa toimia, jos epäilee nollavikaa.
– Ihan ensimmäisenä soitto sähkönsiirtoyhtiöön, josta saa tarkemmat ohjeet. Pääkytkimeen ei kannata koskea, jos keskus on metallia.
– Jos tulee käryä ja tilanne vaikuttaa vaaralliselta, kannattaa olla suoraan yhteydessä hätäkeskukseen.
Tomi Engdahl says:
Aluminum will become defective faster than copper due to certain qualities inherent in the metal. Neglected connections in outlets, switches and light fixtures containing aluminum wiring become increasingly dangerous over time. Poor connections cause wiring to overheat, creating a potential fire hazard.
https://www.nachi.org/aluminum-wiring.htm
Tomi Engdahl says:
What are the basic electrical safety issues and remedies in solar photovoltaic installations?
https://site.ieee.org/clas-sysc/files/2012/11/What-are-the-basic-electrical-safety-issues-and-Version-2.pdf
Tomi Engdahl says:
Advantages of Three Phase System Over Single Phase System
https://www.electricaltechnology.org/2020/09/advantages-three-phase-over-single-phase.html
Tomi Engdahl says:
https://electricalfundablog.com/high-voltage-transmission/
Tomi Engdahl says:
What to Know About Protective Relays
The successful operation of an MV distribution system depends on the proper selection and setting of switchgear relays.
https://www.ecmweb.com/content/article/20896993/what-to-know-about-protective-relays
Tomi Engdahl says:
https://electricalenergyworld.org/what-is-indoor-substation
Tomi Engdahl says:
https://www.electricaltechnology.org/2020/09/difference-conventional-addressable-fire-alarm.html
Tomi Engdahl says:
https://www.controleng.com/articles/your-questions-answered-arc-flash-mitigation/?oly_enc_id=0462E3054934E2U
Tomi Engdahl says:
Cost-effective explosion protection for industrial wireless networks
Wireless Ethernet in hazardous areas is on the rise with integration of explosion-proof enclosures for wireless devices.
https://www.controleng.com/articles/cost-effective-explosion-protection-for-industrial-wireless-networks/?oly_enc_id=0462E3054934E2U
Tomi Engdahl says:
How to Replace an Electrical Outlet – Replace Burnt Out Electrical Outlet and Old Damaged Socket
https://www.youtube.com/watch?v=B16l7RurJuQ
Tomi Engdahl says:
Outlet fire
https://www.youtube.com/watch?v=AKkvJhNGhiw
Student facing charges after viral challenge sparks fire at school
https://www.youtube.com/watch?v=C5XJ1RThaVw
Tomi Engdahl says:
OVERHEAD TRANSMISSION LINES (OHTL) GROUNDING
https://waleedalzahar.blogspot.com/2020/10/overhead-transmission-lines-ohtl.html?m=1
In general, a protection system must be provided for the transmission towers, as well as a safe environment for the personnel working on these towers. A grounding wire is used above the tower. And it has several names earth wire, shield wire, skywire, static wire. Its type can be steel or OPGW wire.
OPGW ground wire is a dual functioning cable are grounding and telecommunications purposes. The conductor is constructed with a central optical fiber core surrounded by helically laid aluminum-clad wires, aluminum alloy wires, galvanized steel wires, or combinations thereof.
Tomi Engdahl says:
https://inspectapedia.com/aluminum/Copper_Clad_Aluminum_Wire.php
Tomi Engdahl says:
https://www.cablejoints.co.uk/blog/article/live-line-working-methods
Tomi Engdahl says:
Generator Protection – Types of Faults & Protection Devices
https://www.electricaltechnology.org/2020/10/generator-protection-faults-protection-devices.html
Tomi Engdahl says:
” The average year sees almost 8,000 electrical fires in the UK alone, with these leading to nearly 4,000 injuries and more than 30 deaths.”
https://247homerescue.co.uk/blog/electrical-faults-lead-to-8000-house-fires-every-year/
or this
https://www.electricalsafetyfirst.org.uk/what-we-do/our-policies/westminster/statistics-england/
The UK attltude towards electrical safety is, at best, pathetic. I hear that it is very common to bypass the main fuses completely, since there is only one or two circuits covering the entire house, and when it blows, everything . In the UK, electrical circuits are usually minimally protected, basic anything goes circuits. 30 amps in a 250 volt system is just insanity. The British do not protect their houses at the source of the residential circuit, but the terminus – the electrical chord.
“All plugs are fused. Most are supplied with 13 amp fuses, and 1 amp, 2 amp and 5 amp fuses are commonly available. Always change the fuse to one which is appropriate for the unit. rootbeer277 says that the fuse should be the one appropriate for the power cord, not the appliance. To a certain extent, these are one and the same, in as much as it’s important that an appliance which will drain 13 amps has a power cord that can cope with it. On the other hand, it’s safe to have a 13 amp power cord on a device that will only use, say, 1 amp. But in that case, I’d rather have a 1 amp fuse.”
https://everything2.com/title/British+Residential+Electric+Wiring
My claim stands – in the UK, 13 amps is the standard protection, notwithstanding the British insanely asinine concept of feeding the entire house with only one fuse and one circuit.
Tomi Engdahl says:
The largest UK panel fuse is 45amp for electric shower, 32 amp for socket outlets, 16amp for some other equipment, heaters and the like, and 6amp for lighting.
Tomi Engdahl says:
Back at the turn of the last century, during the infamous Tesla-Edison wars, the US Congress passed a law, thereafter known as Ohm’s Law (Oportunistic Hegamonistic Monopoly) that decreed America would always, in perpetutiy, and forever, protected by Constitutional mandate, use 110 volts AC as a residential standard. The rest of the world, however, did not feel obligated to follow this law and used 220 volts instead, following Kirchoff.s Postulations, (Kirckoff being a famous and powerful European Institution (EI) politician for watt it’s worth.)
Tomi Engdahl says:
Most dangerous job…
https://youtu.be/oBJyyEAw-6g
Tomi Engdahl says:
https://op.media/teemat/turvallisuus/vaarallisia-sahkolaitteita-ja-leluja-markkinoilla-tuoteturvallisuus-on-yrittajan-vastuulla-96fb405a21de4b72a87dcea092b47d42
Tomi Engdahl says:
Meme GuyNextPrev
Fuse Replacement Guide
Tags: funny, fuse, replacement, guide
https://memeguy.com/photo/155107/fuse-replacement-guide
Tomi Engdahl says:
USA outlets info from
https://www.facebook.com/groups/majordomo/permalink/10161430621239522/
So long as there’s more than one single device (outlet, etc) on the circuit, code allows for 15 amp outlets to be on 20 amp circuits.
The outlets themselves are rated for 20 amp passthrough, they just don’t have the slot to allow for 20 amp appliances to be plugged in. 20 amp outlets with the T slot, in residential, are allowed only on dedicated circuits (such as a clothes washer) with a SINGLE outlet (not a duplex) or hardwired circuit. Commercial is a different ballgame.