I've got a v3f25 drive, I'm looking at it now. And it does have 61u,61n,and 30. The building maintenance guy said they've had leveling issues since it was installed in 2009. When I've got the gap between the sensors and magnets at 3/8" , I have to move the sensor almost 2" up or down away from magnet before the led goes off. I've tried increasing my gap but that leads to inconsistencies. It's like the magnets are way to strong or the sensors are way too sensitive.
