CHAPTER 5: Measurements
•A reversed number 1 indicates a split pair.
•A straight line between pairs indicates a good pair.
•No line between wire pairs indicates an open.
•An X between wire pairs indicates a reversed pair.
•A between wire pairs indicates a short.
•The measured length of the pairs
In the example, OMNIScanner displays split pairs on 1 - 2 and 4 - 5 although they are wired straight through, a reversed pair 3 - 6, an open on wire 7, and a short on wire 8 to the Shield.
Press ESC to exit the WIREMAP screen.
5.3.2LENGTH/DELAY
The Length/Delay function measures a cable’s length, propagation delay, and skew. OMNIScanner will determine whether the cable is open or shorted.
The accuracy of the NVP (Nominal Velocity of Propagation) setting determines the exactness of length measurements. The NVP specified by cable manufacturers is used for all the cables in OMNIScanner’s library. When creating or editing cables, the NVP value can be customized. (See Section 3.5, Setup: Cables, for further information.)
Delay is a measure of the time required for a signal to travel from one end of the circuit to the other. OMNIScanner measures the delay from when the pulse was sent and when the reflection was received. Knowing the speed that the pulse
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