UR-15 Broadband Impedance Spectrum Cable Fault Analyzer - Beijing Kanggaote Instruments and Equipment

FEATURES
APPLICATION
SOFTWARE
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Features
■Non-destruc ve and non-intrusive: It does not necessitate cable disconnec on or disturbance, meaning it can assess cable integrity without causing damage to the cable or surrounding equipment.
■Wide Frequency Range: It can detect a wide range of faults,including subtle defects that may not be identifiable with traditional methods.
■High Accuracy: Provides industry-leading measurement precision with a maximum dynamic range of up to 140dB.
■Fast and Efficient: Requires only 20 seconds per phase in fast mode and 2 minutes per phase in precision mode, ensuring efficient tes ng.
■Versa le Applica on: Applicable for various cable types and voltage levels, such as: transmission and distribu on cables, DC non-armored cables, low-voltage cables.

Test Objects
Low-voltage distribu on cables, non-armored cables, transmission cables,
low-voltage DC cables.

Application
■Power Grid ■Subway ■Railway ■Airport ■Nuclear Power
■Hydropower Power ■Photovoltaic ■U lity
■Electric power tes ng company ■Oil field ■Petrochemical
■Cable manufacturer

Types of faults
■Cable: localized aging, electrical trees, water trees
■Cable Joint: moisture ingress, aging, defec ve workmanship
■Cable sheath: fracture, low resistance short circuit

Principle
■The instrument applies a set of sinusoidal voltage signals with different frequencies (e.g., 9kHz-1GHz) to the cable under test, measures the amplitude and phase of the reflected voltage, and calculates the amplitude and phase of the reflec on coefficient and wave impedance.
■Using Fourier transform, the frequency-wave impedance data is transformed into a me-amplitude curve. By se ng the wave velocity, the me-amplitude curve is converted into a distance-amplitude curve.
■Based on the changes in reflec on characteris cs at different posi ons,the type and severity of defects and faults are evaluated.

Successful Case
■May 2023: During a major overhaul and maintenance shutdown at a domes c power plant, insula on resistance of the Phase B cable was found to be below 17kOhm at a tes ng voltage of 100V.Despite no apparent abnormali es detected in the Time Domain Reflectometry (TDR) results, the UR-15's Broadband Impedance Spectrum (BIS) technology successfully pinpointed the fault loca on at 3.7% of the cable's total length (approximately 2.6meters). Subsequent excava on confirmed the accuracy of the localiza on, revealing that mechanical damage to the cable's sheath resulted in discharge and eventual insula on breakdown.
■June 9, 2023: Collabora ng with experts from a subway power supply company, a diagnos c test was conducted using UR-15 on 263 14-27 tracks of 750V non-armored cables. The test iden fied two issues: a breakage fault and a fault with low impedance, likely caused by moisture ingress. The cable's total length was approximately 500 meters, with the breakage and low impedance located at 63 meters and 81 meters, respec vely. On-site inspec on revealed significant changes in cable layout around the 60-meter mark, where the cable was suscep ble to sunlight exposure and moisture ingress due to altered installa on condi ons.
■ June 1, 2023: A fault simula on test was conducted at the Jiangxi Electric Power Research Ins tute.Ini al tes ng of the Phase B cable (in good condi on) covered the en re length of 548.5
meters. BIS tes ng iden fied four high-resistance faults at 44.6 meters, 124.2 meters, 213 meters, and 283.7 meters, aligning with the predetermined simulated fault points.

■At the beginning of the test, the insula on resistance of the three-phase cable joints was measured as follows: 199MΩ,380MΩ, and 253MΩ. Upon on-site examina on, it was
confirmed that moisture had permeated the joint at the 60-meter mark. A er repair, the insula on resistance improved to 3.94GΩ, 528MΩ, and 338MΩ.Subsequent on-site inspec on revealed thermal aging in the joint at 160m, resul ng in changes to the insula on resistance,which measured 50GΩ, 447GΩ, and 228GΩ a er repair.

■The 220kV oil-filled cable experienced an outer sheath failure at 100V test voltage, the insula on resistance of the B Phase cable sheath is lower than 17kΩ. Time domain reflectometry (TDR) test results showed no significant abnormali es.

Application
■Power Grid ■Subway ■Railway ■Airport ■Nuclear Power
■Hydropower Power ■Photovoltaic ■U lity
■Electric power tes ng company ■Oil field ■Petrochemical
■Cable manufacturer

KGT UR-15