Need some technical help wiring in a tachometer on a Lollar style winder

[kayakerca]

I bought a "real" cheap tachometer off ebay (in transit from China currently) that I want to install on my Lollar style winder. It is not a "no-voltage" input signal like the turn counter I installed and I have no background in electronics what-so-ever. I need help (instruction) on how to wire the tachometer so I don't wreck it. I want to use a reed switch triggered off of a magnet on the drive pulley (which is how I drive the turn counter). I have attached the instructions from the tachometer. Since I am not providing the input in the form of some kind of wave generation, I'm guessing I must use the alternate wiring which has 3 wires: ground, signal, voltage, plus a resistor. I would really appreciate help to set this up property.

tachometer manual.pdf

Thanks in advance.

Take Care,

Jim. . .

[Corcia]

most probably this is going to be a silly question but....
why a tachometer and not a counter?

[kayakerca]

most probably this is going to be a silly question but....
why a tachometer and not a counter?

I have a counter on the winder. I am building a winder like the Lollar winder setup (which I personally think is excellent and a great book). The motor off the sewing machine that drives the winder turns at some unknown speed, and the motor off the fan turns the CAM at another unknown speed. If you knew those speeds and could vary them, you could build pickups that were basically 'side by side' windings to quite scattered (for lack of a better word) windings, AND, you could reproduce that pattern of winding with relative consistency. So, if you add a rheostat to the winder and the traverser, you can control the layering density of the wire on the pickup if you know the ratios of the traverser to winder. For that you need to be able to measure the speed (rpm's) of both motors and be able to vary those speeds. That's where the tachometer comes in. Incorporate the tach into the winder through a DPDT switch (one to the fan motor, the other to the winder motor) and you can vary you pickup layering with consistency. I am using a rheostat from a ceiling fan which has 2 rheostats in it, one for the ceiling fan and a second for the light in the ceiling fan (and it works as I've tested it). Once you get the layering speeds figured out, you use a little EXCEL spreadsheet (Winder speed calculator.xls) to calculate the way you want the layering to lay down on the pickup. I'm just a little anal I guess.

Long winded explanation, I know. But I need to know how to modify the wiring so as not to wreck the cheap tach.

Take Care,

Jim. . .

[Corcia]

I have a counter on the winder. I am building a winder like the Lollar winder setup (which I personally think is excellent and a great book). The motor off the sewing machine that drives the winder turns at some unknown speed, and the motor off the fan turns the CAM at another unknown speed. If you knew those speeds and could vary them, you could build pickups that were basically 'side by side' windings to quite scattered (for lack of a better word) windings, AND, you could reproduce that pattern of winding with relative consistency. So, if you add a rheostat to the winder and the traverser, you can control the layering density of the wire on the pickup if you know the ratios of the traverser to winder. For that you need to be able to measure the speed (rpm's) of both motors and be able to vary those speeds. That's where the tachometer comes in. Incorporate the tach into the winder through a DPDT switch (one to the fan motor, the other to the winder motor) and you can vary you pickup layering with consistency. I am using a rheostat from a ceiling fan which has 2 rheostats in it, one for the ceiling fan and a second for the light in the ceiling fan (and it works as I've tested it). Once you get the layering speeds figured out, you use a little EXCEL spreadsheet ([ATTACH]15580[/ATTACH]) to calculate the way you want the layering to lay down on the pickup. I'm just a little anal I guess.

Long winded explanation, I know. But I need to know how to modify the wiring so as not to wreck the cheap tach.

Take Care,

Jim. . .

I see. well, to wire the reed switch you should connect one lead of the switch to the +V, the other lead to the resistor and the resistor to the "Signal" connector; I don' t know if you already have the reed otherwise you might buy an hall effect sensor (1.99$ from Alliedelec) and wire the 3 leads.
I have just a doubt regarding your method: it works only for constant speeds, during transient states you are not able to know how the machine is winding, but this will happen only during ramp-up/down of both motors

[kayakerca]

I see. well, to wire the reed switch you should connect one lead of the switch to the +V, the other lead to the resistor and the resistor to the "Signal" connector; I don' t know if you already have the reed otherwise you might buy an hall effect sensor (1.99$ from Alliedelec) and wire the 3 leads.
I have just a doubt regarding your method: it works only for constant speeds, during transient states you are not able to know how the machine is winding, but this will happen only during ramp-up/down of both motors

These are the reed switches I used for the no-voltage input counter. Would this type of reed switch work in the wiring scenario you layed out?

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V+ terminal --> reed switch --> resister --> signal terminal (along with leaving the ground terminal unused)

Also, are there any advantages with using a half effect sensor you mentioned in conjunction with a neo magnet on the drive pulley and how is it wired in? I'm guessing that a half effect sensor is a more sophisticated form of reed switch and the 3 leads are marked as to how they would wire into the circuit? As I mentioned in my first post above, I have no background in electronics what-so-ever, so I apologize if my questions sound a little stupid.

I think the tach setup should work well on the winder as if it takes say 8 minutes to wind a pickup, it would only take a fraction of a second to get to speed, after which the layering would consistently be applied in the structure that results from a specific combination of pulley vs. CAM speeds. Remember, there is a separate rheostat for each of the CAM and drive pulley motors and a DPDT switch to change the tach reading between the two motors if tweeting is needed/desired during winding. It will probably be another 3 - 4 weeks for the rest of the parts I plan to use have landed.

Thanks in advance,

Jim. . .

[Corcia]

These are the reed switches I used for the no-voltage input counter. Would this type of reed switch work in the wiring scenario you layed out?

eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices

V+ terminal --> reed switch --> resister --> signal terminal (along with leaving the ground terminal unused)

From the "wiring" point of view they should work, but without a datasheet it is not possible to say it; the most important thing to check is the maximum commutation speed, if you have to measure the speed of a motor that turns at 2400 rpm the reed has to close (and re-open) 40 times in a second (40Hz), so if the reed is "slower"than that you will not be able to measure the speed correctly. as per the picture i've seen those reeds seems not to be high performance one (but it is only my opinion...datasheet is needed).
For the Hall effect sensor it will wire with the 3 pins: +V, GND and Signal, how the pin are assigned varies from sensor to sensor but everything is in the datasheet (that is provided by supplier or very easy to find on the web) once you select the sensor and you have it in your hands it's in a nutshell.

[Jazz P Bass]

Your best bet is to use a PNP proximity switch, as stated in the literature.
A reed switch will never work at high rpm's.
The switch bounce alone will ruin the signal.

[kayakerca]

From the "wiring" point of view they should work, but without a datasheet it is not possible to say it; the most important thing to check is the maximum commutation speed, if you have to measure the speed of a motor that turns at 2400 rpm the reed has to close (and re-open) 40 times in a second (40Hz), so if the reed is "slower"than that you will not be able to measure the speed correctly. as per the picture i've seen those reeds seems not to be high performance one (but it is only my opinion...datasheet is needed).
For the Hall effect sensor it will wire with the 3 pins: +V, GND and Signal, how the pin are assigned varies from sensor to sensor but everything is in the datasheet (that is provided by supplier or very easy to find on the web) once you select the sensor and you have it in your hands it's in a nutshell.

I am using one of these reed switches on the counter and it seems to provide a reasonable count at the 1000 -1100 rpm speed when I time the number of turns in one minute at 1000 rpm (using a hand held tach). Can you use the half effect sensor on a 2 terminal no-voltage input counter as well? If so, which of the 3 leads on the hall effect sensor would not be used?

Thanks in advance,

Jim. . .

[kayakerca]

Your best bet is to use a PNP proximity switch, as stated in the literature.
A reed switch will never work at high rpm's.
The switch bounce alone will ruin the signal.

Is the hall effect sensor referred to by Corcia a PNP proximity switch? Again, I know nothing about electronics.

Thanks in advance,

Jim. . .

[Jazz P Bass]

[QUOTE=kayakerca;230246]Is the hall effect sensor referred to by Corcia a PNP proximity switch?
QUOTE]

Nope.

[kayakerca]

[QUOTE=Jazz P Bass;230248]

Is the hall effect sensor referred to by Corcia a PNP proximity switch?
QUOTE]

Nope.

At the risk of another "Nope", would you be willing to provide a little guidance?

Thanks in Advance,

Jim. . .

[Corcia]

Jim, the hall effect sensor i am referring to ( http://www.alliedelec.com/Images/Pro...K/387-0200.PDF ) is a NPN.
as per the no-voltage input, no, it is not possible to use the hall effect sensor, you need a reed, but if you have doubts about the one you have, you can just buy another on (but first check the max commutation frequency).
please consider that the limit for reed switches is 50 Hz, for Hall effect limit is thousands of Hz, that's why i suggest the usage of Hall effect sensors.
otherwise, as far as you're using a disc with a magnet on to trigger the sensor, you might choose a slotted photoelectric switch or sensor (here a switch: http://www.alliedelec.com/Images/Pro...K/387-0212.PDF ); BTW you can use a slotted photoelectric switch in place of the reed in the no voltage input.

[kayakerca]

Jim, the hall effect sensor i am referring to ( http://www.alliedelec.com/Images/Pro...K/387-0200.PDF ) is a NPN.
as per the no-voltage input, no, it is not possible to use the hall effect sensor, you need a reed, but if you have doubts about the one you have, you can just buy another on (but first check the max commutation frequency).
please consider that the limit for reed switches is 50 Hz, for Hall effect limit is thousands of Hz, that's why i suggest the usage of Hall effect sensors.
otherwise, as far as you're using a disc with a magnet on to trigger the sensor, you might choose a slotted photoelectric switch or sensor (here a switch: http://www.alliedelec.com/Images/Pro...K/387-0212.PDF ); BTW you can use a slotted photoelectric switch in place of the reed in the no voltage input.

Thank you for all the information and help Corcia. I will definitely got with the hall effect sensors for the tachometer. The reed switch seems to work fine on the wind counter as I did a test of it today and ran the winder at full speed for 1 minute (~ 1120 rpm according to my hand held tachometer) and the counter showed 1133 at the end of the minute. Given that I had to start and stop the winder manually, I think the count is very accurate.

Thanks again for all you help. I will let you know how things work out when the tachometer arrives and I get it installed.

[Corcia]

this is what you should do if the pull-up resistor is needed (it should be), in case in this configuration the tacho should not work just remove the resistor.
PS: the resistor is a "bridge" between V+ and Signal, so once you soldered the resistor pin 1 still goes to V+ and pin 3 to Signal.

[kayakerca]

[ATTACH=CONFIG]15589[/ATTACH]
this is what you should do if the pull-up resistor is needed (it should be), in case in this configuration the tacho should not work just remove the resistor.
PS: the resistor is a "bridge" between V+ and Signal, so once you soldered the resistor pin 1 still goes to V+ and pin 3 to Signal.

I was going to ask if the resister was wired in parallel (as a bridge) with the hall effect sensor or in series. You answered the question before I asked. The data sheet for the hall effect sensor lists a large number of versions of the part. Is there one with parameters that is better suited to the tacho I will be using?

Again, thanks for all your help.