DSP-100/2000
Users Manual
Resistance
The resistance test measures the dc loop resistance for each cable pair. The resistance results screen displays the resistance, limit, and pass/fail result for each cable pair. A PASS result means that the measured resistance is less than the limit. A FAIL result means that the measured resistance exceeds the limit.
Length
The length test measures the length of each cable pair tested. The main Autotest results screen shows the length of the cable pair having the shortest electrical delay. Length is displayed in meters or feet. The length results screen displays the length, limit, and pass/fail result for each cable pair. You can change the length units in the SETUP mode, as described in “Selecting a Length Unit” in Chapter 2.
Notes
A 2 to 5 percent difference in measured length between twisted pairs is typical. This difference is due to differences in the number of twists in the cable pairs.
Differences between measured and actual values of cable length can be caused by variations in the cable’s NVP value. To ensure maximum accuracy of length measurements, perform an NVP calibration as described in Chapter 6.
The length test limits include an extra 10% to account for variations in NVP.
A PASS result means that the measured length is within the specified limit for the selected test standard. A FAIL result means that the measured length exceeds the limit.