Dahua NVR4204-P-4KS2 User Manual page 248

Check the Enable box to enable tripwire function.
Click Rule setup to draw the tripwire. See Figure 4-97.
Select SN (Line1/2/3/4) and direction, and then input customized rule name.

Line1/2/3/4: System supports four tripwires. Each SN stands for one tripwire.
Figure 4-96
Figure 4-97
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