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edadmartin July 31st, 2012, 07:19 PM I tested manualy the glass N.O reed switch using a 3/8" x 1/8" rare earth magnet disc. I hooked the wires from my red lion cub I counter to the reed switch, I tried the magnet passing north up, south up, and on edge, all seemed to work but, not consistently. Id like to know which edge or side should pass above the reed switch. The edge, north or south?? how far away from the reed switch should it pass? Also should the reed switch be showing the edge or flat of the reed switch to work correctly? Can the leads of the reed switch be bent to a 90 degree or do they need to be left unbent on installation? Thanks guys
Ronkirn July 31st, 2012, 07:49 PM The problem is "dwell" or the time the magnet is in close enough proximity to the switch. It has to be long enough for the magnetism to 'grasp" the reeds, pull them together, make the contact, and allow those lazy little electrons to head down the wire and shove the counter up one digit…
try it at slower speeds, see what happens
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most of the better winders use an optical trigger to perform the task. The magnet's fast, but it ain't nuthin to light…. light's a speedy little bastuurd… I can wind at about 2500 rpm with one...
Ron Kirn
dsutton24 July 31st, 2012, 07:54 PM Your counter should have a dip switch or jumper that chooses high speed or low speed filtering in the input. 'Betcha if you put it in the low speed position it will work flawlessly.
Magnet reed switches are 'bouncy' as heck, it might take some experimentation to get it right.
Rich_S July 31st, 2012, 09:13 PM I'm leaning the same way as Ron, but I don't think the magnet per se is the problem; it's the mechanical nature of the read switch. A solid-state sensor would work better - like a Hall effect sensor.
There's more to it than that, but it gets hard to describe in a forum post. Your sensor and counter both need to be able the overall speed of the winder (pulse frequency) but also react to the duration of the signal (pulse width). Ideally your sensor should be "on" for half of each rotation and "off" for the other half. In the practical world, it mean a bigger magnet is better than a little one.
I could be more specific if I saw some pics and had the dimensions and speed range of the winder.
Yes, I do this for a living; I'm an industrial automation engineer.
dsutton24 July 31st, 2012, 09:24 PM Ideally your sensor should be "on" for half of each rotation and "off" for the other half.
No, that's not necessary, we use Red Lion counters to count knife tip revolutions using inductive proxes. The knife blades are 3/8" thick and describe a 30" arc.
Yes, I do this for a living. I'm a box factory grease monkey.
(The best way to do what the OP wnats to do is to use a Hall Effect switch to sense the magnet. A prox would also work great if there's a convenient flag or hole to sense. Reed switches are pretty archaic.)
Rich_S July 31st, 2012, 10:13 PM I said "ideally". The real-world take away is "bigger is better", meaning the sensed bit has to be big enough to be "seen".
I like the inductive prox idea, just replace the magnet with a chunky bolt head. A reflective photoeye would work, with a piece of reflector tape of the winder. That's the way optical hand-held tachomters work.
Rob DiStefano August 3rd, 2012, 08:12 AM what ron and others have said - you want an optical/infared trigger for yer counter. reed switches can't accurately handle the high rpm speeds required for a good coil winding machine. a red lion cub 3L000 is a perfect 5 digit counter - now find the correct, and inexpensive, optical trigger.
edadmartin August 3rd, 2012, 12:30 PM My sd card is full ,but Ill post a pic soon so you can see what I have to start with. My dc analog power supply is rated 30volts variable and 3 amps. My DC motor is 24volt variable and has a 1/2" x 1" shaft. My counter is a red lion cub I , It does have a HS and LS lead. I got some glass reed switches on ebay, I know nothing of there stats or if I need a different one. The rare earth magnets are from woodcraft they are 3/8" x 1/8" discs and have major pull for their size. My motor will run 0-1200 rpms max
Keyser Soze August 4th, 2012, 10:27 AM ... - now find the correct, and inexpensive, optical trigger.
Fast
Cheap
Accurate
You can only have two.
Rob DiStefano August 4th, 2012, 10:31 AM Fast
Cheap
Accurate
You can only have two.
fast/accurate - yes.
cheap - depends on whether you wanna spend $5 or $20 or $60.
edadmartin August 8th, 2012, 12:28 AM Would some one post a link to a optical/infared trigger. one that would work with my red lion I counter thanks.
Rob DiStefano August 8th, 2012, 06:37 AM there's a thread going on about an optical refracting trigger for a lion cub 3L, here ....
http://www.tdpri.com/forum/tele-home-depot/338763-simple-cheap-pickup-winder-2.html#post4356415
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