Hi Jason
Thanks for your letter.
What time or cost would be involved to make get the rain and sun light
sensors to work for the louver?
I've not worked with a rain sensor before, but light sensors are easy to
work with, rain's a bit trickier, probabkly 2 hours tho get them playiung
nice with the rest of it
So are you indicating that a washing machine solenoid is not just one
wire wrapped around in a coil or that it is best to have several
parallel wires wrapped around instead of one? I thought all solenoids
had only one strip of wire wrapped around.
one wire many times around, or many wires fewer times around the magnetic
strength is the same (but at different input voltages)
to make the 240V solenoid work on 12V at the samee strength you need to
make the wire 20 times shorter and 20 times fatter (cross section), you
can do that by buying a new fatter wire or by recycling the old one.
looking at the catalog picture of SS-0904 you'd need to drill out a few
rivets to get the bobin out and after rewinding it replace them with new
rivets (or bolts)
What do you mean by the "aluminium tube will slow down the response
rate of your solenoid" are you indicating that there would be less
pulling force in aluminum than plastic?
The peak strenght will be the same, but the aluminium will resist the
changes. softening the the onset and ending of the pull.
never use an aluminium tube for the core of an AC solenoid,
it'll act like a short-circiuted transformer (probably catch fire)
I also wound about 2 meters of the thin wire around a plastic straw
and it did pull a nail. I then wound the wire around an aluminum pipe
about the same diameter and it also pulled the nail with about the
same force.
However, the bigger pipe has not worked yet. Probably because the
weight is heavier and I have not yet wound enough wire. I plan to try
to wire a single strand of wire around the pipe that is maybe 100
meters long. Would that work or do you suggest winding several shorter
strands of the wire around the pipe in parallel.
For maximum strength, figure out how short a piece you can use without it
overheating and use many of that length. (not quite that simple because
you'll be packing them closer together so the heat will be more
concentrated.
For a solenoid the strength is determined by the number of turns and the
current that flows through them, longer wires have proportionally higher
resistance so while you gain more turns you lose bu having less current.
and come out about even. (see Ohm's law)
It is important to
note that I do not want to get the solenoid to get too hot if it is
left on. I could leave it one all the time. Would it be possible to
make a solenoid to perhaps pull 2 kg over a say 2 inches and remain on
all the time that the vent is open?
2Kg x 2", it's good to finally have some figures.
Something like Jaycar YM2734 with a 1 inch lever on the end of the
shaft looks, to me, like a better solution.
It'll have atleast 4.8Kg of force on the end of that arm....
(more atthe start and end because the angle is less)
because at the end of the stroke the crank will be in line with the motion
the motor won't slip when the power is off.
840mW is less power than a solenoid is likely to need too.
Bye.
Jasen
