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Has anyone rigged a tachometer to their winder using a reed switch as a trigger? I assume it could be done. I already use a reed switch for the counter.
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Yes, it can be done. Many counters will do this.Originally posted by JGundry View Post
If the duty cycle (on/(off+on)) is approximately 50%, many digital voltmeters (DMMs) will measure the speed in rotations per second (frequency in Hertz). Multiply by 60 to get rpm.
I do almost the same thing, measuring the frequency of the change-pulse train from the optical encoder on the bobbin axle. There are 500 change pulses per rotation, so multiply indicated frequency (on the DMM) by 60/500 to yield rpm. -
Thanks Joe! I never thought about using a DMM. I will give that a try.Comment
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Thanks again Joe. I tried this with my DMM today and it worked like a charm. It confirmed that the method I was using of using to nail down 1200 RPM was working. I have been using strobe effect of the 60hz overhead florescent light by adjusting the winder speed until the bobbins appeared to stand still to get 1200 RPM.Comment
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do you have any pictures of assembly? This is a great topicOriginally posted by JGundry View PostComment
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I don't have any pictures but it is really very simple. I'm using a reed switch to trigger a Red Lion Cub 5 (maybe a Cub 4, I always forget, the winder is at my office). The counter is lithium battery powered. All I did to get the RPM was to connect my DMM to a couple of leads I added to where the reed switch goes into the counter. I wanted to pinpoint 1200 RPM so I turned the DMM on and set it to hz/frequency and once it read 20 I knew I was at 1200 RPM since the reed switch is closed only once per revolution. The reed switch is triggered by a small rare earth magnet epoxied into the base plate of my tail stock winder.Comment
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