Counter Idea

[David King]

There's nothing wrong with the 16.6V, just put a 1K or 5K pot in series with any old LED and put your meter in series as well in DCA mode. Turn the pot from max down until you get to 20ma. Measure the DCR across the pot and substitute that value of resistor.

[tonedeciple]

There's nothing wrong with the 16.6V, just put a 1K or 5K pot in series with any old LED and put your meter in series as well in DCA mode. Turn the pot from max down until you get to 20ma. Measure the DCR across the pot and substitute that value of resistor.

That's a good idea. I'm going to keep the 16.6VDC and do either this or add a 7805 regulator and some capacitors. I know for sure I'll order at least five of those QRB1114s just to play it safe.

[-Elepro-]

This all makes sense, except for one thing; how did Elepro come up with the 4k7 R2? I need to know this since I want to drop the power source to 5VDC.

with 4k7 at 12volt you have more than 2mA.... it is enough for counter...

[tonedeciple]

with 4k7 at 12volt you have more than 2mA.... it is enough for counter...

I couldn't figure out the requirement for the counter. At any rate, here is what I've come up with by relying on everyones help here and elsewhere. It may be overkill, but I think it'll work. I have to order a few components, but I've got the power supply regulated at 5VDC now.

[MistaT]

That pretty much will work, but I am a bit concerned about the 10k resistor. At 5 volts, you will only draw 0.5 ma. I am not sure that is enough current flow through the sensor for it to "turn on" hard enough for the counter to "see" a voltage low.

If it were me, I would make that something like 270 ohms. This would give you enough of a current flow through the opto to it would turn on hard enough for the counter to see the pulse.

[tonedeciple]

That pretty much will work, but I am a bit concerned about the 10k resistor.

I wondered about that as well. I got that number from a similar config:

http://classicamplification.net/winder/OPTEK-CUB4.pdf

...and this recommendation:

QRB1114 IR Sensor (SKU: 35140) - HVW Technologies

I guess I can't start low and work up until I have enough of a pulse to trigger the counter accurately.

[MistaT]

Well basically there is a lot of room here for a very wide resistance range. Honestly I am surprised at their recommendation of 10k, but if that is what they recommend, then I guess it should work.

Like I posted earlier for getting my Cub5 counter going, I used a 560 ohm with a 12V power supply.

So like you said, start with a 10k if you are comfortable with that and see if it works. You certainly won't blow anything up for sure. If your circuit doesn't work, then cut the resistance in half. Keep doing that until it does work. But do your ohms law calculation so you know how much current is flowing through your circuit and keep the current below all of your devices max. allowed current, and you should be fine.

[tonedeciple]

Honestly I am surprised at their recommendation of 10k, but if that is what they recommend, then I guess it should work.

Of course they don't know what my counter requires. Elepro stated 2mA should be enough which I calculate at 5V to be about a 2k resistor. Are 1/4-watt enough? Or should I opt for 1/2-watt.

I have to say this whole experience has been a lot of fun It has reall blown the dust of the left side of my brain!

[MistaT]

Well here is the deal for calcualting power needed for a resistance.

P = I * E

Where:
P = Power in watts
I = Current
E = Voltage

So lets take ur example with a 2k resistor. Since you calculated 2ma, I will use that.

P = 0.002 x 5 = 0.01 watt <== This is how much will be dissipatted by the resistor.

With resistors, its a good idea to take your calculated dissipation and double it (safety factor) then go to the next highest wattage.

OK all that to say that 1/4 resistors are just fine. But at least now you know the thought process in the future.

BTW, I'm glad this is a learning experience for you, and I am glad to help out. Like I have said before, I get a lot out of this forum, and I am thrilled to be able to give back a little.

[RedHouse]

I wondered about that as well. I got that number from a similar config:

http://classicamplification.net/winder/OPTEK-CUB4.pdf

....

These resistor values are derrived from the Optek application note 213 which describes in detail the requirements of the LED and collector current for the transistor. They work, I use the setup daily.
(with a CUB counter)

I couldn't figure out the requirement for the counter...

I Looked back over these pages in this thread but couldn't see exactly which counter you bought, there were two posts asking if a certain one was any good but I didn't see which brand/type you actually bought?.

Anyway that's why the CUB4 and CUB5 are really well suited for our application, they have Schmidt trigger inputs and can handle up to 4-28V signals, and have a "high speed" counting input for up to 5kHz (not the CUB4L8 though) which is fast enough to count the turns on a Dremel tool.

Winding at a rate of 2000 RPM is actually 33.3333 revolutions per second, which re-stated is a mere 33.3Hz signal and a walk in the park for the CUB4/5. The ongoing debate over duty-cycle within these counter threads is not critical with the CUB counters and optical switch, CUBs trigger on a rising (or is it falling?) edge of the input signal, not the apeture of duty-cycle time.

On my 2nd winder (the one folks refer to where I showed the Optek/CUB thing) I used the circuit shown which gives the specified collector current for the sensor to function correctly (see app note) and I used what equates to a 20% window or duty cycle, the counter handles this quite easily at that machines max speed of 1500 RPM. On my latest (3rd) winder I used a 25% window just because it was easier to mill out.
(my most recent winder has the opto-vane built right into the aluminum bobbin flange)

[tonedeciple]

I Looked back over these pages in this thread but couldn't see exactly which counter you bought, there were two posts asking if a certain one was any good but I didn't see which brand/type you actually bought?.

I bought a Redington 7600-731DC for $5. When I hooked up everything initially, it counted almost all the way to full speed before stalling. I don't know the actual RPM but it's a sewing machine motor with a 1-1/2" drive pulley spinning a 4" bobbin pulley.

Unfortunately I couldn't find any specs for this basic counter so some guess work went into the input requirement. The 4k7 resistor worked well with 12VDC (16.6VDC no load according to my meter).

I used your R2 equation for determining my R3. I used the values from the QRB1114 spec sheet. However, it doesn't take into consideration what the counter might need. I figure I'll start with 10k.

BTW, your site was REALLY helpful. Thanks for sharing the info. I hope to do the same eventually, though my winder won't have quite the capability as yours. Although I have an idea for an auto traverse using a servo and a servo tester circuit. But that's for another day. Can't wait to see version 3.0!

[RedHouse]

I bought a Redington 7600-731DC for $5. When I hooked up everything initially, it counted almost all the way to full speed before stalling. I don't know the actual RPM but it's a sewing machine motor with a 1-1/2" drive pulley spinning a 4" bobbin pulley.

Unfortunately I couldn't find any specs for this basic counter so some guess work went into the input requirement. The 4k7 resistor worked well with 12VDC (16.6VDC no load according to my meter).

I used your R2 equation for determining my R3. I used the values from the QRB1114 spec sheet. However, it doesn't take into consideration what the counter might need. I figure I'll start with 10k.

BTW, your site was REALLY helpful. Thanks for sharing the info. I hope to do the same eventually, though my winder won't have quite the capability as yours. Although I have an idea for an auto traverse using a servo and a servo tester circuit. But that's for another day. Can't wait to see version 3.0!

Hmm... bummer the data sheet isn't available. I just tried a few searches w/o success either.

[tonedeciple]

It Worked!

Thanks for all of the help from everyone. The counter does exactly what I'd hoped it would do. And, at speed faster than I can comfortably wind. Here is a link to a video. Please be aware the wiring is proto. I'll solder it to a circuit board when I get a chance.

YouTube - Winder Test

[packrat99]

How about this counter? Do you think it might be a good choice regardless of the method for tripping? It's super cheap.

American Science & Surplus : Does This Count?

I just bought four of these and they work great, they are internal powered just like a watch, it never turns off. It counts pulses applied to one of the rear terminals, reset is done by applying a positive voltage to the other terminal. I use a 9 volt battery switched through a reed switch to the counter input (5-30 volts). You can't beat these for 5 bucks. I use it on my mini-lathe winder with a reed switch just above the chuck and a small magnet stuck to the chuck. It works well to about 1000 rpm, then I think the switch bounce causes it to start skipping. The only very minor drawback is it won't count backwards, only up. Really neat little counter. I've wound eight pickups so far and no problems with the counter at all.

Initially I tried to use an optical sensor, the counter was happy with it, but the sensor needed to be in a dark enclosure, wouldn't work with the bright lights needed to keep an eye on the wire. When I have time I'll try another type, this one was out of an old 5 1/4 disk drive, detected the notch in the discs, I guess those were pretty dark inside.

BTW, I used Jason's drawing to make a cam that runs off of the little threading indicator on the lathe, it works pretty well but is having some reliability issues, it tends to bind once in a while. It drives a rod back and forth just like his design and since it is geared to the lathe, doesn't need a separate motor. Does a pretty smooth job, I just need to beef it up a little bit.

For the price of that Schatten winder, I would consider a mini-lathe and have a tool that will do lots of things for a little more money.

[tonedeciple]

It works well to about 1000 rpm, then I think the switch bounce causes it to start skipping.

My counter doesn't appear to skip with the phototransistor even at full speed, which is about 2,250 rpm if my calculations are correct. I like to wind at around 1,100rpm and after about 5-6 minutes, I had a 6k Ohm humbucker bobbin with 44 awg wire. I feed the wire by hand, so I had to stop the winder a couple of times to check the coil shape.

My only concern now is the life expectancy of the motor. It gets pretty hot after 4-5 minutes, even with a fan.