Hall Effect Sensor?

[Dave293]

Hi

I am in the process of making a new counter for my winder and I have a question.
How do I connect the the hall effect to my counter? I am out of ideas, what to I connect and where?

The counter is an electronic counter kit, I have assembled it and it works great.
Here is more info on the kit, including schematic.
http://www.oceancontrols.com.au/counters_timers/k129.pdf

Here is the hall effect I have and some info on it.
http://blast02.lns.mit.edu/targets/ion/manuals/Allegro_3503.pdf

Thanks
Dave

[Joe Gwinn]

Hi

I am in the process of making a new counter for my winder and I have a question.
How do I connect the the hall effect to my counter? I am out of ideas, what to I connect and where?

The counter is an electronic counter kit, I have assembled it and it works great.
Here is more info on the kit, including schematic.
http://www.oceancontrols.com.au/counters_timers/k129.pdf Four digits isn't really enough for pickups, where one can have more than 10000 turns. Five digits are a better choice.

Here is the hall effect I have and some info on it.
http://blast02.lns.mit.edu/targets/ion/manuals/Allegro_3503.pdf
Wrong hall sensor. This one is linear, intended for measuring the magnetic field and yielding a voltage that varies smoothly and proportionally with magnetic field, while the counter expects a binary logic signal. One can make this work, but some added circuitry is needed to generate the needed logic signal when the hall-sensor output voltage passes a specified threshold.

There are hall sensors (from Allegro and others) that contain the necessary logic and yield a binary output signal, well suited to driving a counter (if the voltage levels are matched).

Perhaps a CUB3 counter and a reed switch would be the quicker way home.

[Sock Puppet]

Hi,

As the hall sensor you have is linear, then you'll need to convert the output to a -Ve going pulse for the clock input using a comparator as shown here:

http://ecow.engr.wisc.edu/cgi-bin/get/ece/317/schowalter/317lab6fan.doc

The magnet polarity is important.

HTH

S.

[mkat]

Four digits isn't really enough for pickups, where one can have more than 10000 turns. Five digits are a better choice.

Joe, the K129 wraps to 0 and continues from there once reaching 9999. I may be mistaken, but that doesn't sound like an issue to me, wind to 1000 after 9999, unless the overflow causes some other problem.

Regards,

Michael

[Dave293]

Four digits isn't really enough for pickups, where one can have more than 10000 turns. Five digits are a better choice.

As said this counter starts back at 0 after 9999 or you can add 2 of these counters together and have an 8 digit counter if needed.


Wrong hall sensor. This one is linear, intended for measuring the magnetic field and yielding a voltage that varies smoothly and proportionally with magnetic field, while the counter expects a binary logic signal. One can make this work, but some added circuitry is needed to generate the needed logic signal when the hall-sensor output voltage passes a specified threshold.

There are hall sensors (from Allegro and others) that contain the necessary logic and yield a binary output signal, well suited to driving a counter (if the voltage levels are matched).

Perhaps a CUB3 counter and a reed switch would be the quicker way home.

I bought this hall sensor as it was the only sort I could get locally. Maybe a reed switch would be a better option.

Thanks everyone for the help!:)

[Joe Gwinn]

As said this counter starts back at 0 after 9999 or you can add 2 of these counters together and have an 8 digit counter if needed.Sounds workable, but a bit clumsy.

I bought this hall sensor as it was the only sort I could get locally. Maybe a reed switch would be a better option. It's the locally that's the problem. Unless you are very fortunate in your location, it's pretty much essential to use the catalog distributors like Mouser, Digi-Kay, Allied, Newark, et al. These companies have at least ten times the selection of even the largest of brick-and-mortar stores, and collectively they exceed brick-and-mortar by a factor of 100.

The disadvantage is that their catalogs are pretty big and intimidating, making the web interface almost useless if you don't know exactly what you are looking for. So, order the paper catalogs (which are free), as browsing is far easier in a book.

[Dave293]

Thanks!

I though about ordering from mouser but I have some pickups I want to mind now and didn't really want to order just a hall effect and maybe some eyelets all the way from the US :) I'll wait to I have a bigger order and order the right one then, for the time being i'll use a reed switch.

[mkat]

Sounds workable, but a bit clumsy.

It does work and it's much cheaper than the cub counters.

[Phil m]

Micheal,

If you're looking at CUB's locally they are expensive but you can get a used CUB3 on ebay for $20 and get it shipped to you. With shipping I paid $35 for mine and it was a great investment. The guy also made money shipping it to me because that thing weights no more than 100 grams.

[mkat]

Micheal,

If you're looking at CUB's locally they are expensive but you can get a used CUB3 on ebay for $20 and get it shipped to you. With shipping I paid $35 for mine and it was a great investment. The guy also made money shipping it to me because that thing weights no more than 100 grams.

Ok, sounds like a good deal Phil. I'll keep an eye out for them.

[Joe Gwinn]

If you're looking at CUB's locally they are expensive but you can get a used CUB3 on ebay for $20 and get it shipped to you. With shipping I paid $35 for mine and it was a great investment. The guy also made money shipping it to me because that thing weights no more than 100 grams.It's that locally again. They cost $31 new from Digi-Key: http://catalog.digikey.com/scripts/partsearch.dll?Detail?name=RLC03-ND.

One thing I like about the CUB3 is that they have user-replaceable batteries. The counters with built-in lithium batteries are disposable, as the batteries cannot be replaced without surgery.

[Phil m]

Micheal's in Sydney, Australia. That's why I suggested ebay as I got mine from there. There's a Red Lion distributor here, however you're looking at $60-$100 AUD for a CUB.

Thanks for the digi-key tip though. $31 is cheap and I'll probably get another one soon :)

[mkat]

Micheal's in Sydney, Australia. That's why I suggested ebay as I got mine from there. There's a Red Lion distributor here, however you're looking at $60-$100 AUD for a CUB.

Thanks for the digi-key tip though. $31 is cheap and I'll probably get another one soon :)

Ok, here is a rough estimate of the cost looking at the product and international shipping prices at the Digi-Key web site:

CUB3: USD$31.32
Shipping to Aus (USD$18 - $32 depending on destination, estimate only): USD$20
Processing fee on all international orders except Canada: USD$6
Total: USD$59.32, AUD$75.19

So, not really better than buying local (Australia) it seems.

[Joe Gwinn]

Ok, here is a rough estimate of the cost looking at the product and international shipping prices at the Digi-Key web site:

CUB3: USD$31.32

Shipping to Aus (USD$18 - $32 depending on destination, estimate only): USD$20
Processing fee on all international orders except Canada: USD$6
Total: USD$59.32, AUD$75.19The AUD is 0.7887 USD, so USD $31.32 becomes AUD $39.71, not AUD $60-$100, so it seems that the price in Australia is significantly higher than the US. Shipping in bulk is very cheap, so that isn't the reason. More likely, it's the lack of competition in Oz.

So, not really better than buying local (Australia) it seems.The real issue with locally is the lack of selection and of competition. Shipping is less of an issue if one doesn't have to cross the Pacific Ocean, but still most of that USD $20 is per-order overhead, so one would benefit from fewer, larger orders. And slow delivery is cheaper.

[mkat]

The AUD is 0.7887 USD, so USD $31.32 becomes AUD $39.71, not AUD $60-$100, so it seems that the price in Australia is significantly higher than the US. Shipping in bulk is very cheap, so that isn't the reason. More likely, it's the lack of competition in Oz.
Joe, not sure what you mean about it not being AUD $60-$100. If you look at my post above, you'll notice that it is the total cost including shipping and the international processing fee. I recalculated it today and the total is AUD$72.59. Also, the cheapest shipping Digi-Key offer is via United States Postal Service Global Express Mail @ USD$18. As you say, shipping in bulk may be cheaper, but it's relative. There is no way we're are going to get it cheaper than that (shipped to Australia) from Digi-Key. Local to the US is cheap for this product, not here.

The real issue with locally is the lack of selection and of competition.
I agree with this to a certain extent and possibly in this case. But, what I've seen, is that it is rare to get a really good deal here at all.

Regards,

Michael

[David Schwab]

Joe, not sure what you mean about it not being AUD $60-$100. If you look at my post above, you'll notice that it is the total cost including shipping and the international processing fee. I recalculated it today and the total is AUD$72.59

When I do the conversion from USD$31.32, I get AUD$39.736.

[mkat]

When I do the conversion from USD$31.32, I get AUD$39.736.

That's what I got too:

CUB3: USD$31.32, AUD$39.74
Shipping to Aus (USD$18 - $32 depending on destination, estimate only): USD$20, AUD$25.24
Processing fee on all international orders except Canada: USD$6, AUD$7.57
----------------
Total: USD$59.32, AUD$72.55

[Joe Gwinn]

Joe, not sure what you mean about it not being AUD $60-$100. If you look at my post above, you'll notice that it is the total cost including shipping and the international processing fee. I recalculated it today and the total is AUD$72.59. Hmm. I see that I misread your posting.

Also, the cheapest shipping Digi-Key offer is via United States Postal Service Global Express Mail @ USD$18. As you say, shipping in bulk may be cheaper, but it's relative. There is no way we're are going to get it cheaper than that (shipped to Australia) from Digi-Key. Local to the US is cheap for this product, not here.The point being made is that shipping and handling is partly per-order, not all per-gram, so it makes sense to make fewer but larger orders.


I agree with this [about local sources] to a certain extent and possibly in this case. But, what I've seen, is that it is rare to get a really good deal here at all.That's what I've heard too, so while parity with sources on the other side of the world will never be achieved, one can greatly reduce the impact.

War story: In the 1970s I worked in Sweden on and off, and then for a year. On 12 December 1973, I bought a HP-45 calculator in the US, for $400.00 (which is $1,816 in 2007 US dollars). Shortly after arrival in Stockholm, I went to some kind of industrial show, where the local HP Rep had a HP-45 on display, held down with a clear plastic collar bolted to a heavy podium. The price seemed a little high to me. The claim was that this was due to shipping. I did the exchange-rate conversion on the HP-45, and determined that for the difference, one could fly from Stockholm to New York, run into the city and buy a HP-45, run back to the airport and fly back to Stockholm, and be money ahead. The Swedish price was about double the US price. Oops. The nice salesman was not happy with me. My business partner was laughing through the whole episode. This kind of gross overcharging was typical in Sweden.

I have a quote for a HP-65 from HP Sweden, in Stockholm, dated 18 March 1974. The quoted price is 5,275 SvKr (excluding taxes), and the then exchange rate is 4.67 SvKr per USD (hand annotated by me on the quote), so this is USD $1,295.55 (1974 dollars). At the time, the US price was USD $795, so the ratio is 1129.55/795=1.42. Only a 42% markup from US retail price. At least it wasn't 100%. We didn't buy the HP-65.

[mkat]

There are hall sensors (from Allegro and others) that contain the necessary logic and yield a binary output signal, well suited to driving a counter (if the voltage levels are matched).

What about the counter debounce with a hall sensor, will this come into play as with the reed switch? Can you provide more info on an appropriate sensor for this kit?

[Joe Gwinn]

What about the counter debounce with a hall sensor, will this come into play as with the reed switch? Can you provide more info on an appropriate sensor for this kit?There is no bounce with a hall sensor, and counters like the CUB3 are pretty tolerant anyway. The key is the minimum pulse width that will register: It needs to be no shorter than five or so milliseconds. This will allow reliable counting with a reed switch, and if a counter can handle a reed switch, it can also handle a hall sensor (assuming you are using one intended for this purpose, not a linear sensor).