Concox GT03C User Manual page 9

e.g.
FENCE,ON,0,N22.57139,E113.87710,5#
It means the radius is 500 meters（radius 1=100M，2=200M····and so on）
The device will reply "OK" if set successfully. As long as the device goes in or out of this circular
area, it will send alarm to the SOS numbers.
You can also set current location coordinates as the centre of the circular fence,
"FENCE,ON,0,0,0,radius#" (This SMS command is only available when device get located)
 Go-in fence SMS:
Any number can send the following message"FENCE,ON,0,latitude,longitude,radius,IN#" to
turn on circular fence function
e.g.
FENCE,ON,0,N22.57139,E113.87710,5,IN#
It means the radius is 500 meters（radius 1=100M，2=200M····and so on）
The device will reply "OK" if set successfully. As long as the device goes in this circular area, it
will send alarm to the SOS numbers.
 Go-out fence SMS:
"FENCE,ON,0,latitude,longitude,radius,OUT#"
e.g.
FENCE,ON,0,N22.57139,E113.87710,5,OUT #
It means the radius is 500 meters.（radius 1=100M，2=200M····and so on）
The device will reply "OK" if set successfully. As long as the device goes out of this circular area, it
will send alarm to the SOS numbers.
(2) Rectangle fence
Specify two points in the map and use them as diagonal line, you can draw a rectangle area, which
is the rectangle fence.
 Go in/out fence SMS:
Any number send the command
upper left corner, the latitude of lower right corner, the longitude of lower right
e.g.
FENCE,ON,1,N22.541183,E113.916,N22.557743,E113.892334#
The terminal will reply "OK" if set successfully. Any time the terminal enter or leave this rectangle
fence, it will send alarm message to the preset SOS numbers.
 Go in fence SMS:
Any number send the command
"FENCE,ON,1,the latitude of upper left corner, the longitude of
"FENCE,ON,1,the latitude of upper left corner, the longitude of
corner#".