Press the ESCAPE key to exit.

Editing the Cable Type

To display the EDIT CABLE screen, press Cable (F1) from the Ready screen, then press Edit (F2). This screen displays the characteristics of the cable you will be testing.

Press the or arrow key to highlight the (cable) Name or NVP (Nominal Velocity of Propagation) field. The Impedance field is for reference only and does not affect test results. The highlighted field will be enclosed in a box. Use the Scanner keypad to enter the Cable Name or the NVP value.

Press Del (F2) to delete the character at the cursor.

If your Scanner has an alphanumeric overlay on the keypad, use the keypad to enter the cable name. If your Scanner does not have an alphanumeric overlay, press Edit (F2) to edit the name. See Chapter 4: Editing, Printing & Updating for more information on editing.

Note: If you change the information for a factory supplied cable type and do not edit the cable name, an asterisk (*) will appear before the cable name.

If you are not sure of the NVP value, press GetNVP (F4) to calculate it. See Calculating NVP for more information.

Press Save (F1) to store the new settings and exit. If you have changed the cable information, press Default (F1) from the CABLE SETUP screen to select it as the cable type to use during testing.

Press the ESCAPE key to exit without saving.

Calculating NVP

To display the CABLE NVP screen, press Cable (F1) from the Ready screen, then press Edit (F2); then press GetNVP (F4).

For an accurate Length test, the NVP (Nominal Velocity of Propagation) must be set correctly. NVP is a measure of how fast a signal travels down a cable compared to the speed of light. It is usually between 60% and 90% and is specified by the cable vendor. The Scanner has a large library of cables with the manufacturer’s specified NVP.

This screen lets you calculate the NVP for cables over 50 feet (15.24 meters) long. The PentaScanner and PentaScanner Cable Admin calculate the NVP based on the longest wire pair in the cable. The PentaScanner+ calculates the NVP based on the shortest wire pair in the cable.

You can use the CABLE NVP feature to create a custom cable type when the cable type is not known.

If your Scanner has an alphanumeric overlay on the keypad, use the keypad to enter the cable length. If your Scanner does not have an alphanumeric overlay, press Edit (F2) to edit the length. See Chapter 4: Editing, Printing & Updating for more information on editing.

Press Del (F2) if you wish to delete the character at the cursor. After you have entered the cable length, press Calc (F4) to calculate the NVP.

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Microtest TSB-67 - 568A Annex E manual Editing the Cable Type, Calculating NVP