Ok, now we are getting somewhere. Bear with me, only a couple more questions:
My circuit pulls-in the relay if the Lift is up, and allows it to drop out when the lift is down. If you use a relay with a 1C contact configuration (SPDT, Common, Normally Open, and Normally Closed contacts), you can choose if the Trimble gets a CLOSED contact if the Lift is Up or if the Lift is Down. Which way does the Trimble want it to be?
The sensor voltage is proportional to Lift position. As originally drawn, my circuit will pull-in the relay when the sensor voltage is between 2V and 12V, or about 15% Up to 100% Up. I can adjust my circuit to switch the relay at any particular position of the lift. At what point in the Lift travel would you prefer to start the data logging?