We have a motor that need to install two standalone vibration sensors very close, but we are not sure how close can be. We read in another doc that every sensor should be 3 ft apart from the modem, but we couldn’t find info between these two sensors together.
There is no minimum distance for sensors. You can mount them so close they are touching.
One suggestion though would be to look at this product if you are monitoring two points adjacent to each other:
OK, Thanks for input