FT video on fuses and electric cars mises the point

Impetus

The British financial newspaper, the FT has a video this evening on the topic of fuses blowing and electric cars.

Virtually every country in Europe operates with trip switches instead of antiquated fuses, aside from "the British Isles". RCD trip switches are faster to activate and safer. All new property in Ireland should be built with 2 pin + earth plugs/sockets, as was the case when Siemens installed electricity in Ireland back in the day. Those with British 3 pin flat plugs who buy a new house can use adapters, until they have changed the plug or appliance. In the continental wiring system one has a single power cable running from virtually each socket to a trip switch. Using a standard plug that is small, convenient and international.

The British style 3 pin flat plugs are not fit for purpose. If you use them at 2 or 3kW demand, they will heat up - a potential fire risk. If somebody touches a live wire, they will probably be dead before a fuse blows. Not so with an RCD trip switch.

The British system (copied by the Oirish) needlessly duplicates the fusing application - trip switches react far faster. And a low power connection to each tripswitch, is far safer than the British style ring main.

When the British came out with the 3 pin flat plug, it worked OK from a power transmission perspective up to 13 A. As more and more people got electrocuted they had to install an insulation on the 3 pins of the plug. Leaving the metallic contact between the plug and socket inadequate causing overheating at higher wattage levels.

The electric car is another reason to dump the three pin flat socket and ringmain wiring in a home or office. All it causes is problems.

https://www.ft.com

(bottom of page for the video).






https://www.ft.com

brightspark

You are obviously unfamiliar with the Irish wiring systems currently in use (and to a large extent have been for quite some time)

RCDs do not replace fuses, (an RCBO might). The equivalent to a fuse is an MCB which does not protect against electric shock either.

Houses in Ireland are now protected by a combination of RCDs and MCBs, or RCBOs on socket circuits, and this has been the case for about 30 years in all new installations.

The 13A plug top will probably only heat up dangerously if there is a faulty connection in the plug or socket. The flat pins "should" lead to a longer lasting good connection. I have rarely worked with the European sockets but from my experience the old 15A round pins used here previously were prone to becoming loose.

Ring mains are less popular here now, and prohibited in parts of installations. Their real danger comes from when the "ring" gets broken, it isn't easy to notice until either properly tested or another fault occurs.
A correctly wired ring main is no more likely to cause a fatal electric shock than a radial circuit. 32A or 16A MCB won't blow before a fatal shock occurs

I think you will find the European plugs are part insulated now to prevent inadvertent finger contact with the live pin.

One major advantage the 13A style has over the European style is that the polarity is maintained, the European plug can be plugged in either way, meaning you don't know which pin is live.

Whilst improvements to domestic electrical safety are always progressing, I very much doubt that electric cars are going to result in a complete redesign of domestic wiring systems.

brightspark

Just watched the video...

What they are concerned about is an issue concerning the maximum load that can be drawn at a time.

Chargers of about 11Kw are being proposed, (equivalent to an power electric shower). Hardly going to stop you putting the kettle on, but might cause a problem if you using the shower or electric cooker!

An 11Kw charger won't be something that you just plug in, it will need a separate circuit.

The video is also warning about the demand put on the grid, everyone comes home at the same time, cooks dinner, charges their car and probably taking a shower as well. Peak demands are a difficult issue when generating and distributing power.

Impetus

brightspark wrote: »

I think you will find the European plugs are part insulated now to prevent inadvertent finger contact with the live pin.

One major advantage the 13A style has over the European style is that the polarity is maintained, the European plug can be plugged in either way, meaning you don't know which pin is live.

Whilst improvements to domestic electrical safety are always progressing, I very much doubt that electric cars are going to result in a complete redesign of domestic wiring systems.

2 pin plugs maintain their polarity because there is an earth PIN in the socket which only allows the 2 pin plug to be inserted in one direction.

You can't have finger contact with a 2 pin plug, because the socket surrounds the plug as one inserts it - ie the pins are out of view and out of touch by the time they make contact with the power.

The British style 3 pin flat sockets look ugly and with the growth of appliances one needs many of them. Look at a Huff Haus https://www.huf-haus.com/de made for the mainland European market, with the sockets installed in a British version of the Huff Haus, and how ugly the sockets look in a perfectly wired, factory made minimalist building using German socket systems for comparison.

The bottom line is that the fuse in the plug seldom blows - it is the trip switch (call it by any name you like) that blows first. Logically every socket or group of sockets should have a cable running back to a dedicated trip switch to allow one to use the lowest amperage power into each group of sockets.

I find the 2 pin plugs never get warm - and I put this down to the insulation that was added to the defective British plug after they discovered people being electrocuted with their flush socket design. BT had the same problem with the phone connector. BT in typical British fashion did not opt for the RJ7 used in most other countries. Instead they re-invented the wheel, and in the process created a phone socket (for a POTS line) that little children could get their fingers into and if the phone line was in 'ringing mode' at the time, the child got a nasty shock.

Neither Britain, nor Ireland has a good reputation for the quality of its engineering or design. Wiring and plumbing standards make this abundantly obvious. If there is a dumb way to re-invent the wheel, it will be done in IRL or GB or both! (eg the postcode/eircode compared with the European, US, Russian, or Japanese norm of a 4 to 7 digit number).

Impetus

brightspark wrote: »

Just watched the video...

What they are concerned about is an issue concerning the maximum load that can be drawn at a time.

Chargers of about 11Kw are being proposed, (equivalent to an power electric shower). Hardly going to stop you putting the kettle on, but might cause a problem if you using the shower or electric cooker!

An 11Kw charger won't be something that you just plug in, it will need a separate circuit.

The video is also warning about the demand put on the grid, everyone comes home at the same time, cooks dinner, charges their car and probably taking a shower as well. Peak demands are a difficult issue when generating and distributing power.

I have installed heat exchangers to heat and cool a house I inherited in Cork, and they use a fraction of the power that other systems (eg oil, gas etc) use. 400w gives one about 2kW equivalent of heating (with the latest R32 refrigerant). My next plan is to use solar panels to power the heat exchangers - and as I am away most of the year, much of the power I generate from PV solar can be fed back to the grid. I haven't looked into the feed-in tariff offerings in Ireland yet. Anybody know how much one can make per kWh by selling power to the grid?

If I had an electric car (I am waiting for battery efficiency to improve) I could do a slow charge of the car batteries from the PV cells - or draw on the credit balance from the feed-in tariff to pay for my driving energy.

brightspark

Impetus wrote: »

2 pin plugs maintain their polarity because there is an earth PIN in the socket which only allows the 2 pin plug to be inserted in one direction.

Completely misleading. They can be inserted either way.

https://en.wikipedia.org/wiki/AC_power_plugs_and_sockets

The Schuko connection system is symmetrical and unpolarised in its design, allowing line and neutral to be reversed

Impetus wrote: »

You can't have finger contact with a 2 pin plug, because the socket surrounds the plug as one inserts it - ie the pins are out of view and out of touch by the time they make contact with the power.

Surprisingly though children can put their fingers into sockets in Germany as the sockets are not shuttered, unlike most other countries.
The Schuko sockets can also take "Europlugs" however not safely, this is also a design flaw.
Other countries such as Denmark have previously used round pin plugs that didn't have recessed sockets so they also had issues with inadvertent finger contact.

Impetus wrote: »

The British style 3 pin flat sockets look ugly and with the growth of appliances one needs many of them. Look at a Huff Haus https://www.huf-haus.com/de made for the mainland European market, with the sockets installed in a British version of the Huff Haus, and how ugly the sockets look in a perfectly wired, factory made minimalist building using German socket systems for comparison.

To be honest no plug/socket is really aesthetically pleasing.

Impetus wrote: »

The bottom line is that the fuse in the plug seldom blows - it is the trip switch (call it by any name you like) that blows first. Logically every socket or group of sockets should have a cable running back to a dedicated trip switch to allow one to use the lowest amperage power into each group of sockets.

"Call it by any name you like"???? You obviously don't understand that the shock protection is given by the Residual Current Device (RCD). The MCB which replaced the fuses in a consumer unit offers minimal protection against shock unless the fault to earth is very high, e.g. a live conductor directly touching metal.

Impetus wrote: »

I find the 2 pin plugs never get warm - and I put this down to the insulation that was added to the defective British plug after they discovered people being electrocuted with their flush socket design.

I would put it down to substandard plugs. Cheaper plugs have more problems with loose connections, I will admit that the fuse-holder within the plug is often the main source of the loose connections.
However the fuse in the plug top is a safety device if correctly fitted. It should "blow" before the cable to the appliance overheats in the event of an overload.

When I was an apprentice it was well known not to use the cheaper brands of sockets in areas such as kitchens etc that would have high demands and if price was a factor to only use cheaper sockets where the usage would be light. I suspect that in an effort to reduce prices in many developments cheaper outlets were more widespread.

However the Schuko plug is rated at 16A, as opposed to the BS1363 which is only rated for 13A, which is about the current drawn by a 3kW load such as a "rapid boil" kettle.

Impetus wrote: »

Neither Britain, nor Ireland has a good reputation for the quality of its engineering or design. Wiring and plumbing standards make this abundantly obvious. If there is a dumb way to re-invent the wheel, it will be done in IRL or GB or both! (eg the postcode/eircode compared with the European, US, Russian, or Japanese norm of a 4 to 7 digit number).

I don't think any country gets everything right, there are lots of conflicting reasons why, but to say that neither Britain nor Ireland has a good reputation for engineering is wrong, even more so when you go back to when these standards were being considered.

brightspark

Impetus wrote: »

I have installed heat exchangers to heat and cool a house I inherited in Cork, and they use a fraction of the power that other systems (eg oil, gas etc) use. 400w gives one about 2kW equivalent of heating (with the latest R32 refrigerant). My next plan is to use solar panels to power the heat exchangers - and as I am away most of the year, much of the power I generate from PV solar can be fed back to the grid. I haven't looked into the feed-in tariff offerings in Ireland yet. Anybody know how much one can make per kWh by selling power to the grid?

If I had an electric car (I am waiting for battery efficiency to improve) I could do a slow charge of the car batteries from the PV cells - or draw on the credit balance from the feed-in tariff to pay for my driving energy.

A 1:5 power return for the heat pump is impressive, I had previously heard it was about 1:3 or 1:4. As you say combining that with PV to supply the input energy and the heating will be free (apart from installation and maintenance costs).

A lot of the renewable technology I've looked at appears to have about a 10 year payback, but it's been a couple of years since I last checked.
Unfortunately that 10 year pay back doesn't allow for maintenance and failures with no certainty that the system won't need to be completely replaced soon afterwards completely eroding any savings. Of course if oil/gas prices increase to the levels forecast by the people selling renewable technology then the savings would be more.

No feed in tariffs available here!



As to charging your car via solar, you will need a lot of panels

e.g. according to

https://en.wikipedia.org/wiki/Nissan_Leaf

The 30 kWh battery has a range of 172 km.
Ignoring the losses you would need a lot of panels to generate 30kWh

If for example you wanted to fully charge over 10 hours you need to be generating approx 3kW from the panels.

Looking at this site

http://www.theecoexperts.co.uk/how-much-electricity-can-i-generate-solar-panels

A 1m2 square panel has a theoretical potential of generating about 1000W...but they only operate at about 15-20% so you would need at least 5 to generate 1000W, to get 3kW you would need 15. That is assuming you can get 10 hours of sunlight, in reality you won't, and also your roof location, angle etc may reduce the power generated further.

So a minimum of perhaps 15 square meters of panels just to charge the car (but probably double as we are in Ireland so not always sunny).

Almost manageable...but my car is at work during the day, for many days throughout the year it's dark when I leave and dark soon after I get home. Solar panels don't work overnight!! So perhaps a spare battery to leave at home to charge during the day?

bk

brightspark wrote: »

Chargers of about 11Kw are being proposed, (equivalent to an power electric shower). Hardly going to stop you putting the kettle on, but might cause a problem if you using the shower or electric cooker!

brightspark, you are clearly very well informed on this subject and probably know better then me. But just FYI for anyone reading this, seemingly both Tesla and BMW have car chargers that monitor the load on the home and reduce the car charging rate if someone for instance turns on an electric shower.

brightspark wrote: »

An 11Kw charger won't be something that you just plug in, it will need a separate circuit.

Yup, when you buy a new EV in Ireland, ESB eCars will install for free a dedicated 3.3kWh EV charge point which is connected directly to the distribution board:

https://www.esb.ie/docs/default-source/ecars/ecars-terms_and_conditions_-2016

Hardly any EV owners are just using a random home plug (granny cable), partly because it is slower charging.

brightspark wrote: »

The video is also warning about the demand put on the grid, everyone comes home at the same time, cooks dinner, charges their car and probably taking a shower as well. Peak demands are a difficult issue when generating and distributing power.

Not really a major issue, most people who buy EV's charge them at night and use night rate electricity. Which is very much off peak and very welcome by the ESB.

Nearly all EV's come with the ability to control or schedule when they start and finish charging. For instance when you get home at 6pm, you plug it in, but it doesn't start actually charging until past midnight.

In future when we get smart meters, this will all get even smarter and EV's will only charge when electricity is at it's cheapest or when the wind is blowing.

To be honest, this video is a bit FUD and a bit scaremongering.