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Discussion Starter #21
Rather than coiling it perhaps a hanging zig-zag arrangement, as was (is?) used on some liquid fuel hoses, might be another option.
I was considering this but was thinking how a thick cable would be able to arrange like that (any ideas?), thanks for the help though :)
 

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Charging "cables" don't break from being left out in the rain.

The cable is completely waterproof.

An unplugged end connector can suffer degradation from the weather, hence my suggestion to design a better "mousetrap" holster.
 

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Suggest for your project, that you completely keep away from Rapid charging cables.

You will need an engineering degree to properly understand their design and function before you even attempt to improve upon their user functionality.
 

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A cord winding system for an EVSE charging station could work, if it is designed to only energise when fully unwound, to prevent heat buildup in an otherwise coiled up lead. I think a lot of these designs have a set of brass or carbon contacts and a circular tracked PCB inside them, so the cable drum can connect to the fixed wiring of the holder. A little bit like the brass contacts behind a car steering wheel for the horn, airbag and radio controls. How that sort of design would stand up to 32A flowing is another issue for you to research.

EVSEs currently have a number of electrical safety features built into them which have to pass before the EVSE contactor will supply power to the car. Having an EVSE wall box with an integrated cable holder like this might work, providing it checks the cable is fully extended. Something to count the number of rotations of the cable drum to verify full extension? There's also the clutch / pawl mechanism inside one of these drums that clicks so the cable does not automatically recoil unless tugged or a button is pressed to rewind the cable.
122380

One thing I hate about that sort of design is the socket on the end would just dangle there in free air. No weatherproofing to it. A holster for the socket "gun" would be good, maybe a lid over a larger enclosure?

One other thing which might be useful for you is how an EVSE works. There's an open source project called OpenEVSE which has some useful documentation online.

Good Luck!
 

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Finn, my gge charger setup exactly fits your description of trip hazard, untidy cables lying around, etc. I have 2 chargers I use frequently, so that makes my gge even more untidy & dangerous!

I aldo have wondered about how to get a tidier & safer solution, but haven't come up with anything yet. One thing you do not want is a spring-tensioned system that's constantly trying to pull the charge cable back into the holder/whatever. When the plug is in the car, you do not want sideways tension on it - the control signal pins can be a bit sensitive & fussy about not being pulled to one side. So you put some sort of lock/ratchet to stop this, problem solved. Then after a charge, you release the ratchet, and the whole cable flies back at a dangerous rate of speed, possibly abrading the cable sheath, possible making the plug flap around dangerously & damaging that. That's what me ancient Electrolux vacuunm cleaner does, but I can control the speed, and th 13A flex is ok snaking over carpet. For an EVSE this is a no-no, so you put in some sort of speed control, maybe a viscous damper/whatever.

All this is getting rather complex, suggesting the design't going the wrong way. Simpler is often better. So you scrap the spring idea, and make it hand-would. Speed problems are now solved, but instead you have the problem of how to wind 8m of thickish cable back into the holder without dragging it over the ground. You can't be at the charger and at the car's end of the cable at the same time! So you have to lift it from the car end, and carefully drop it back beside the holder, and then you can wind it neatly away. But you got your hands wet.muddy lifting & supporting the cable while you wound it. Time for another think.

Ideally we (at least I do) want something that holds the cable out of the mud/dust, lets us stretch it from the charger to the car along whatever route we choose, and lets us retract it simply without getting our hands dirty or scraping the cable. The desire to keep the cable itself clean (=safer) suggests to me that the support for the cable needs to be distributed along the cable, maybe continuously, maybe every 50 cms or so. Winding the cable up around a drum has the problems of possible overheating if cable is used when wrapped tight, so maybe that can be avoided by folding the cable in a zig-zag manner? Or winding it in a loose, well ventilated coil would be ok. But tbh, these charging cables (especially th e32A ones) are pretty stiff things and won't like being flexed. They much prefer being coiled.

When you coil a flex that has been lying flat, it likes to acquire one complete rotation of the coil as it gets put into one loop. This way, the individual cores don't get stretched to alonger or shorter lengths. If the coil isn't rotated, and you insist on winding it flat, the outer cores will be at a larger radius than the inner cores, so there's a lot of stress (force) and strain (defoemation, stretching/compressing) going on. By acquiring one rotation of the cable per loop, each core si sometimes at a larger radius, sometimes a smaller one, so there's so overall cumulative stretching or compressing of the cores. The energy required to twist the cable by one rotation per loop is far less than the energy required to wind it flat, so the coil prefers the lower energy configuration of one twist per loop

I had wondered about some kind of scissor-jack/ extending-concertina-tongs type of arrangement, possibly with plastic roller wheels, which extends from below the charger & snakes its way across the drive. Problem is it probably wouldn't let the cable twist as it extends. Ideally I'd like the cable to be sitting flat in a circular try, and as I extend the snake-gadget, the cable comes out of the tray, and does one complete rotation of the cable & plug for every complete loop that comes out of the tray. There's a circular->linear problem here, waiting to be solved! Perhaps you can come up with some rotary-concertina-thing? If it could be 3D printed in sections which clip together to suit any length of cable that would be a bonus!

There's a nice 3D printable cable-protector thing, see here.
http://www.thingiverse.com/thing:14716
I've used these to enclose 13A cable which travels up & down on my 3D printer as the heated baseplate rises & falls. I wonder if it's possible to make a bigger version of this which has a bit of rotation built-in, so as you extend it, it travels in a coil-like way? Then if the cable can be held in the middle, so it's say 25 cm from the ground, that would keep it clean?
 

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Your problem(s) definition.

  • Having to transport cable around everywhere
    • Leave cable at home all the time (tethered) or leave it at home and secured (non thethered)
  • Cable gets dirty and wet when lying on ground
    • Who cares, one never touches the cable, just the connector, this is the only bit that needs to be clean. In addition, make sure your driveway/paving/hard landscaping is occasional cleaned, has drainage etc and dont be a minger
  • Safety hazards of leaving electric cable out in the rain
    • there are no safety hazards for the cable itself, you just need to keep the end connector out of direct rain
  • Theft of cables
    • imagined problem? Make sure your insurance covers this unlikely eventuality
  • Untidy look of cables lying around
    • Instal a free socket EVSE, keep the charging cable in the shed, garage, under your bed, whatever
  • Trip hazard for pedestrians
    • Train them to switch off their smartphones and look where they are walking. Otherwise pull and spare cable off the front doorstep.
  • Each car has a cable, whereas it would be more environmentally friendly to have a cable at each charging station
    • eh? are you sure? what is the proportion of cars to chargers in the UK. Methinks its probably close to unity anyhow
  • Elderly having to bend down to pick up cable
    • The elderly need training in the same manner as your blind pedestrians. They need to taught to not touch the cable, just the end connector which of course will be stowed at hip height (approximately) thus negating any need to bend.
OK OP, really sorry to have to use the above tone and sorry for any cold water on your brillant idea, but really all the above are problems that are non existent or have simple trivial solutions.

Regards
 

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OP, not sure if you are familiar with the "story" of NASAs design brief and project for a space pen.....meanwhile the Russians came up with a very cunning solution.
 

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OP, not sure if you are familiar with the "story" of NASAs design brief and project for a space pen.....meanwhile the Russians came up with a very cunning solution.
That story is apocryphal.
 

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I was considering this but was thinking how a thick cable would be able to arrange like that (any ideas?), thanks for the help though :)
Cable laid ropes have a preferred coiling direction. Perhaps work towards a cable that practically coils itself to a diameter that fits the bag. Maybe some regularly spaced clips too along the length.
 

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I don't recognise most of those problems.
But i do see a potential problem that you could design a usefull product for.
theives stealing cables from cars.
You could make a cable tidy locking box for the car boot
 

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Discussion Starter #38
For your design technology course, may I suggest that you design a better parking holder for the type 2 connector, than any currently on the market. One that latches, provides a degree of rain or snow protection and is easy to mount to typical domestic dwelling exterior wall.
For use as my market research could use please re-state the problems you have with your parking holder, many thanks :)
 

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When you coil a flex that has been lying flat, it likes to acquire one complete rotation of the coil as it gets put into one loop. This way, the individual cores don't get stretched to alonger or shorter lengths. If the coil isn't rotated, and you insist on winding it flat, the outer cores will be at a larger radius than the inner cores, so there's a lot of stress (force) and strain (defoemation, stretching/compressing) going on.
I thought cable cores were spiral wound so there is no shortening/lengthening of the cores
 
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