Inductive triggered relay to start dust collector?
#15
Last night, after I posted, I did a Google search and found this;  https://www.youtube.com/watch?v=VHgaBxTPEPM
It appears that the amount of current can be adjusted. I didn't pay too much attention as I was looking for a wire wrapped around a larger one or the donut coil I had mentioned. It didn't look too hard; perhaps that was what the P.C. board did on the industrial vac.s.

Your relay may work fine with 12vac. If I was going to change to D.C., I would use a full wave bridge rectifier. You also stated that "wrapping an 18g wire around one of the hot wires to Sawstop was enough to induce 12vac between the wrapped wire and earth ground". I don't fully understand that. Did you show voltage between the two ends of the 18ga.?

Although I enjoy tinkering and learning new things this might all be just an interesting thought process fo me since I just saw this https://www.amazon.com/Current-Sensing-N...3252629578 when I was looking for a current sensing breaker.
Sign at N.E. Vocational School Cabinetmaking Shop 1976, "Free knowledge given daily... Bring your own container"
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#16
(10-31-2022, 09:32 PM)MstrCarpenter Wrote: Last night, after I posted, I did a Google search and found this;  https://www.youtube.com/watch?v=VHgaBxTPEPM
It appears that the amount of current can be adjusted. I didn't pay too much attention as I was looking for a wire wrapped around a larger one or the donut coil I had mentioned. It didn't look too hard; perhaps that was what the P.C. board did on the industrial vac.s.

Your relay may work fine with 12vac. If I was going to change to D.C., I would use a full wave bridge rectifier. You also stated that "wrapping an 18g wire around one of the hot wires to Sawstop was enough to induce 12vac between the wrapped wire and earth ground". I don't fully understand that. Did you show voltage between the two ends of the 18ga.?

Although I enjoy tinkering and learning new things this might all be just an interesting thought process fo me since I just saw this https://www.amazon.com/Current-Sensing-N...3252629578 when I was looking for a current sensing breaker.


The voltage I measured was between one end of the 18g wire and ground.
I suspect it may be ghost voltage as mentioned by someone else earlier, that will disappear when a load is applied, I’ll check that and let y’all know once I have a rectifier. 

The Amazon item you posted looks like a nicely packaged version of almost exactly what I’m trying to do. 

I could use the switch on it to switch the power on from a power supply and power the coil on a contactor and it would achieve exactly what I’m looking to do.

I’ve ordered one to at least play with, will continue working on my original plan as parts come in.

I’m also curious about learning new things.

Thanks 
Duke
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#17
As was suggested the voltage I had measured was ghost voltage that disappeared as soon as a load was applied.
Unfortunately wrapping more wire, and even thicker wire several more wraps did not result in more voltage as I expected.

Going to have to try wire with less insulation as well as different directions of wrapping the wire.

As MstrCarpenter linked to the inductive switch worked perfectly to sense current through the wire and close the low voltage relay. If I can’t get my own inductive coil to produce 24vac (that’s what contactor coil needs as mentioned also by )MstrCarpenter
Then I’ll use the inductive switch to make an auto switch.

Duke
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#18
(11-03-2022, 08:03 PM)JDuke Wrote: As was suggested the voltage I had measured was ghost voltage that disappeared as soon as a load was applied.
Unfortunately wrapping more wire, and even thicker wire several more wraps did not result in more voltage as I expected.

Going to have to try wire with less insulation as well as different directions of wrapping the wire.

As MstrCarpenter linked to the inductive  switch worked perfectly to sense current through the wire and close the low voltage relay. If I can’t get my own inductive coil to produce 24vac (that’s what contactor coil needs as mentioned also by )MstrCarpenter
Then I’ll use the inductive switch to make an auto switch.

Duke

A lot more turns are needed.  Not sure what you mean by wrapping in a different direction but it wont work as you are thinking.    Use the type inductive switch you linked but with a built in delay off .  Roly
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