The CircleScout GX utilizes periodic GPS reporting to track the position of your center pivot. It also can tell you when your pivot starts or stops.
Each CircleScout GX contains a cellular modem, GPS chip, rechargeable battery, and a printed circuit board to interface with the control circuits on your center pivot. The connection cord to the CircleScout is simply looking for a constant ~ 120 VAC signal when your pivot is walking. When it sees this signal go from low to high, it triggers an event that the pivot started. When it sees this signal go from high to low, it triggers an event that the pivot stopped.
When the pivot starts walking, the rechargeable battery in the CircleScout begins to charge and usually will fully charge in 5 to 10 minutes. When the pivot stops walking; the rechargeable battery maintains power to the cellular modem, which then transmits the event code that the main AC power supplied by the pivot has dropped out.
The CircleScout GX is designed to parallel off the forward and reverse run control circuits of the pivot. Because of this simple and easy to install design, it does not provide remote control functionality and cannot prevent a pivot from operating normally.
If a CircleScout GX fails to report a stopped pivot event the most likely causes are poor cellular coverage on the spot of the field where the stop occurred, or a battery that didn't fully recharge since the pivot was started.