Max distance to a magnetic alarm sensor

[Ira]

My specific use case is for an Elk M1G panel. I want to use a magnetic alarm sensor, e.g., a window open/close sensor, at a driveway gate about 1500' from the house. I can run a cat6 cable underground to the gate. Can I use one of the twisted pairs to connect the sensor to an M1G zone, or is 23AWG "not enough"? I would rather not use multiple pairs for this.