Blobis (Customer) asked a question.
Is there a proximity sensor switch or something like it that will turn on or off when detecting rotation?
I don't need it to measure RPM,
Just need it to close circuit when a shaft starts to spin and open circuit when the shaft stops.
Automation direct sells Relays that monitor the frequency of a prox switch for speed monitoring.
https://www.automationdirect.com/adc/shopping/catalog/safety/safety_relay_modules/speed_monitoring_safety_relays#start=0
I don't need to monitor the speed. Imagine you have a shaft, and when it spins the sensor turns a light on, when the shaft stops the light turns off,
Can you place a chain sprocket on the shaft?
Here's a photo of a machine I built where I needed to confirm a shaft turned. The sprocket is triggering a proximity sensor. The proximity sensor was wired to a PLC, and in the program I had a one-shot from that prox to an off-delay timer. The prox was triggering the timer so its .DN bit was always true. If the .DN bit goes false, I knew the shaft was not turning.
Sounds like a prox with an off delay and I don't think one exists. You'll have to pair the sensor with an off-delay timer or PLC.
https://pharessensors.com/index.php/zero-speed-switch-sensor-model-zs09p-for-conveyors-and-more/
It needs a "flag" to sense, like key stock in the shaft end. Might be good for applications where there is no PLC.
If there is a PLC, there are a couple of ways to do this with no coupling to the shaft. One has already been mentioned and another is with a polarized retroreflective photo eye and a piece of polarized reflective tape on the shaft.
Either of those cases involves a timer (or two) that gets reset on each rising and/or falling edge of the sensor input.
Never seen these before. Thanks!
I think z28's speed monitoring relay would work well and you can set the speed range for an output to be on just about anything above zero speed.
Off-delays would work assuming your not stopping on a flag keeping the sensor on unless you're using a PLC like Todd is.
After thinking about it we use some Telemecanique XSA-V12151 for detecting that a fan hasn't thrown its drive belts. There is a pot on it you adjust for the speed setting
https://tesensors.com/us/en/product/reference/XSAVEQ5062
look at product called Whirligig, we had 100's of conveyors this product worked very well very simple. I cwould call it a zero speed sensor, when shaft turning a contact would close. Had a lot of these with very few problems.
These "Motor Standstill" safety relays are made for that exact purpose:
https://www.automationdirect.com/adc/shopping/catalog/safety/safety_relay_modules/motor_standstill_monitoring_safety_relays#start=0&sort=
From the technical specs:
"speed monitoring safety relay modules provide safe standstill detection on 3-phase and single-phase motors by monitoring remanence voltage. • Can monitor motor voltages up to 690 VAC or VDC • No external sensors necessary • Independent of direction"