Sunrise Global CE4000, Cable Explorer TDR Module TDR Basics, Measurements, Locating Cable Faults

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Chapter 3

Measurements

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Chapter 3 Measurements

TDR BASICS

Locating Cable Faults

The CE4000 TDR has two cable test modes, Auto and Manual. Select the desired icon on the Main menu for the preferred mode of operation. Press the MENU key at any time during operation and the unit will return to the Main Menu screen (Figure 3-1).

Figure 3-1

The CE4000 operates on the same principle as most TDRs. A test pulse, typically called the incidence pulse is transmitted into the cable under test. The pulse travels down the cable at a speed that is controlled by the properties of the cable. The speed is called the VOP or velocity of propagation and is measured as a percentage or decimal fraction of the speed of light. When the pulse reaches a discontinuity in the cable some of the energy (all of the energy if the cable is open or shorted) is reflected back up the cable toward the original source. The TDR measures the time required for the round trip of the reflected pulse from the TDR, from which it was launched, to the fault and back to the TDR. The distance to the fault is then calculated by the formula:

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Contents CE4000 CE4000 Cable Explorer TDR Disclaimer Contents Maintenance And Service Introduction Instrument Overview IntroductionGeneral Information CM1000 Mainframe and CE4000 Module Mainframe Input/OutputCM1000 mainframe and CE4000 module CE4000 Keyboard Functions History Preparation for USE Unpacking And Initial InspectionGeneral Information Shipment Contents Charging InstructionsSafety Precautions First Time Module Installation CE4000 Cable Explorer TDR Power Up To Self Test Screen SetupGetting Started Main Menu Screen Detail Setup Overview System Setup Detail Time & Date Cable Select Detail Insert Save changes by pressing the Save F3 key Cable Test SET Cable Length Cable Type CE4000 Cable Explorer TDR TDR Basics Locating Cable FaultsMeasurements VOP Measurements TDR Trace Loss and Return Loss RTL Trace Signatures TDR Tests with the CE4000 Auto Test Mode Display CE4000 Cable Explorer TDR Zoom Peak Hold Save Manual TDR Measurements Display M1/M2 Pulse Gain / POS Measurements CE4000 Cable Explorer TDR Stored Files CE4000 Cable Explorer TDR Next Adjust Compare Load Performance Specifications and KEY Features Power EnvironmentInterfaces DisplayMaintenance and Service Battery ReplacementInternal Rechargeable Battery General MaintenanceCleaning Troubleshooting Firmware Upgrades CompactFlash Card ReplacementCE4000 Cable Explorer TDR Warranty Technical SupportReturning Equipment to Sunrise Customer’s ResponsibilityMaintenance and Service CE4000 Cable Explorer TDR Appendix Cable Data Additional Cable dataVOP