IT angle
This may displace the claims of the Power over Ethernet people that their socket is the only 'power outlet' which is the same in every country on earth.
US, Euro e-car makers back 'standard' AC/DC jack
Audi, BMW, Daimler, Porsche and Volkswagen have joined Ford, Chrysler and General Motors to back a standard fast-charge connector and jack for e-cars. The system combines a multi-pin AC port with a two-pin DC inlet. Slow, but cheap, overnight charging is handled by the AC lines, but drivers will be able to use the same …
-
-
Friday 4th May 2012 10:55 GMT Blofeld's Cat
@Extra pins
Split phase, signalling and vehicle detection.
There's some pretty hefty voltages (600 VDC) and currents (400 A) involved as well.
-
Friday 4th May 2012 10:46 GMT Lee Dowling
That has to be the ugliest socket I''ve ever seen in my life. Even SCART and DVI were more elegant.
What was wrong with just putting a pair of DC pins side by side in a large-enough connector, and maybe one small one for some kinda "sense/data" pin that could also act to key the connector's polarity? AC pins are going to differ in voltage and frequency anyway and you're going to have them handle them in the car by, well, converting them to DC. Surely that's better done at the fuelling station AND home charger than anywhere else, otherwise they would just add weight to the car and be skimped upon (and be upgrade-proof!)?
Or is this is a drive to "sell" you 100 KWh of AC electricity that is only 90KWh once you have DC losses and only 80KWh once your battery gives you it back? Push the thermal / conversion losses onto the poor sap stupid enough to buy an electric car?
Still have yet to actually see anyone in real life top up an electric car, though, and I live inside the M25 and do an awful lot of driving.
-
-
Friday 4th May 2012 11:14 GMT Lee Dowling
Re: Connector design
And how does that help make the connector more complex (and the same connector is used for "home" fill-ups too - that's one of the stated points of the standardised, dual-power adaptor!)?
That amount of power, in a female socket means you have to jab metal objects into the end to short it. It will be suitably fused, but more importantly it will probably have contact-sensing (like any modern "jumpstart" battery - if you short the connectors at any point, no power flows - power is ONLY applied when it's probed the other end and found a load that's suitable for charging and operates on dumb principles because lead-acid batteries don't have any circuitry!). Failing that, the "keyed" connector should ensure that there's contact and could even be designed to relay correct physical contact of the connector back to the "pump" which only switches on when it's been told that the connector is mated properly (can be as simple as a spring-button lock on the connector that only operates when "latched" into the correct socket).
If it hasn't, I refer to my original point - what a crap, overcomplicated connector.
And I'd rather have two huge meaty inch-thick DC cables that do auto-sensing than all that gumph which just looks ripe to go wrong in the case of a sheared cable or damaged connector (you're telling me that little old ladies trying to force that into their car's port sideways for years at a filling station won't eventually break those plastic interiors and make the AC contact the DC?).
It just seems an incredibly ugly, overcomplicated and poor design to make dual AC/DC connectors and pumps and then rely on convertors inside your car (and your problem if they blow up and you can't charge your car any more) rather than just pushing ONLY DC and doing all the messy, expensive conversion before you shove things down a standardised, minimalist connector that needs as little as possible done to it afterwards and metering it from actual, usable DC power at the point of filling.
-
Friday 4th May 2012 12:29 GMT Ru
Re: "rather than just pushing ONLY DC"
If your car accepts standard AC, you can charge it anywhere regardless of the availability of charging equipment. You could just nail a suitable plug onto the end of a standard domestic power lead or industrial 3phase outlet... this is pretty much how basic home charging is done on most e-vehicles anyway.
Making the charger optional makes life easier for everyone, except the sorts of people who get angry about power sockets.
-
This post has been deleted by its author
-
Friday 4th May 2012 11:42 GMT Blofeld's Cat
Re: Connector design
It wouldn't be beyond the wit of man to automatically stop the e-car from driving off if the charger's attached!
Quite so. Unfortunately people tend to underestimate the capabilities of idiots.
Motorhomes have interlocks to prevent the engine being started if they are plugged into a hook-up bollard, and yet I repair or replace several hook-up bollards every year.
It just takes a small piece of grit, a loose connection or the supply being turned off and twang!
-
-
-
Saturday 5th May 2012 18:28 GMT Alan Firminger
Guesswork
Look at the pictures. And remember that cars travel around.
The plug mains connector shows what we can assume is two pins and earth. There is also space for different configurations around the earth.
The socket shows five pins for mains and a blank space. One pin has to be neutral.
The plug will give connection to one of four voltage options.
Your car has an input voltage appropriate to the market, which means you have a connector that selects what it wants. Public recharge stations, perhaps in hotels and car parks, offer all the voltages.
-
-
-
Friday 4th May 2012 11:14 GMT Charles 9
Re: Anti tamper?
IIRC the AC part of the plug's designed to be used in an enclosed setting, such as a garage. If the chav can get into the garage to reach your plug, you have bigger problems than them making off with the cable.
As for the DC part, this is meant for quick applications so exposure there would be limited: more like at the filling station.
-
Friday 4th May 2012 11:30 GMT Omgwtfbbqtime
Re: Anti tamper? @Charles9
The charging stations I have seen so far (in LocGov owned/operated car parks) do not have their own cables attached as far as I could see.
I have never seen any of these bays occupied - though the maximum stay 4 hours sign Sunderland Council have inflicted on these bays may have more to do with that.
-
Friday 4th May 2012 15:23 GMT Phil O'Sophical
Re: Anti tamper? @Charles9
>: do not have their own cables attached as far as I could see.
That's because such cables are likely to suffer the same fate as garage airlines. Give the charging point a socket, and have the cable attached to the car. That way you have some change of finding a usable charging point.
Or just use a liquid like biodiesel or ethanol. Tried & tested.
-
Saturday 5th May 2012 12:53 GMT Charles 9
Re: Anti tamper? @Charles9
"Or just use a liquid like biodiesel or ethanol. Tried & tested."
And then rejected. Diesel is too polluting, and biodiesel too low in volume to use mainstream. Meanwhile, ethanol isn't as powerful as petrol and can't be produced in mainstream volumes without eating into food supplies. Meanwhile, synthetic petrol production is still in the initial phases. I would be great if it worked out, thought we'd still need a source of vast power to produce it all (*yawn* call me when you can present a cost-effective land-effective non-fossil non-nuclear power plant design in the 2GW range or so--then we'll talk).
-
-
-
Friday 4th May 2012 12:01 GMT Steve Button
Re: Anti tamper?
Charles 9, errrr No. these things are popping up outside of many buildings (like the office I'm sitting in which has a couple, although I've never seen them used). It's a really good point about anti tamper. It just needs a place where you can attach a padlock or something similar, but you just know someone is going to be left sitting on the tarmac because a) someone has decided to maliciously unplug them or b) someone else with an electric car hijacks your juice.
-
-
Friday 4th May 2012 11:19 GMT Lee Dowling
Re: Anti tamper?
They'd be too busy sticking two pounds into a charging station and then finding ingenious way to blow it up like connecting it to a nearby lamppost, arcing them to each other, sticking their finger in it or whatever else.
Electric cars are a really stupid idea at the moment anyway. Charge time in hours is the cause of the problem you describe and one of their biggest downfalls. A tank-filling time in minutes means most people don't leave the car unattended while fuelling. A similar charge time would do the same but because of the sheer huge nature of the power involved (the equivalent of a tank full of petrol, which is extremely safe considering its energy density), it's not going to happen for a very, very, very long time and even then still be more dangerous.
Hopefully, we'll stop all this electric junk soon and come up with something that's likely to actually work better than a milk float (all-electric since the 1960's, I believe).
-
-
-
-
-
Friday 4th May 2012 13:39 GMT Anonymous Coward
lmgtfy @easyk
No, not two 120V lines. Residential distribution is single phase 240V. There are transformers on the poles with a center tap. Every house has three wires: two hot and one neutral/ground connected to the center tap on the transformer and to ground in the house. Use the two hot wires, you get 240V; use one hot and the neutral you get split-phase 120V. The electric panel divides half the 120V circuits on one hot lead, and the other half on the other lead.
Electric water heaters, stoves/ovens, heating systems, clothes dryers, and the rare heavy duty appliance all run on 240V; everything else runs on 120V.
Is that the same as two 120V lines that are 180° out of phase? Seems like it could be hard to keep two independent 120V feeds in phase; easier (if more expensive) to use a transformer to split a single phase 240V supply.
-
Saturday 5th May 2012 18:45 GMT Alan Firminger
230 volt supply was agreed as a European standard giving an acceptable compromise between the continental 220 volt standard and the UK's 240 volt. This was settled about 1988, I am not going to research that - just accept a long time ago.
Prior to this and after we all had and have a supply spec within plus and minus 6 % . The continentals had many supplies below tolerance, so they made an effort and solved two problems, probably helped by a grant from Brussels.
There are still 220 volt goods on the continent and many of us have legacy 240 v items. No matter.
-
-
This topic is closed for new posts.
Biting the hand that feeds IT
