Cable Fault Locator TDR RI-407 “SWIFT+”
for Power Lines applications

Cable Fault Locator TDR RI-407 – a high-precision digital reflectometer specifically designed to determine distances to all types of irregularities and faults in power cable lines: open circuit, short circuit, coupling, cable splice, parallel branch, wet cable.

The implementation of additional high-voltage methods makes it possible to locate high-resistance faults on power cables.

Cable Fault Locator TDR RI-407


It can also be used on any other metal cable lines, communication cables, signaling and control cables, computer networks, television and radio frequency cable lines.

Overview

Overview

TDR RI-407 cable fault locator implements the following measurement methods:

  • Time Domain Reflectometry (TDR)
  • Arc Reflection Method(ARM or SIM )*
  • Impulse Current Method (ICM)*
  • DECAY  travelling wave method*

* when used in complex with high-voltage pulse generators (HVPG), for example: ADG-200-2 “STINGRAY-M”

Time Domain Reflectometry (TDR)

the most accurate and safe mode – effective for diagnosing low-resistance faults (less than 1 kOhm) and short circuits, searching for cable line breaks, joints/splices, parallel branches, etc.

More about this method:

Time Domain Reflectometry (TDR). Theoretical basis.

Time Domain Reflectometry (TDR). Practical techniques.

The method allows you to perform the following works:
• cable length measurement;
• measurement of distances to impedance inhomogeneities or faults;
• measurement VoP (v/2) of the line at its known length;
• determination of the nature of cable fault.

The TDR method is based on the phenomenon of partial reflection of electromagnetic waves in places where the impedance of a line changes. When measuring by the TDR method, a short voltage probe pulse is sent to the line, which, partially reflected from the impedance inhomogeneities, returns back. The reflected pulses return to the TDR-device some time after the sending of the probe pulse. Knowing the signal velocity of propagation in the line and the delay time of the reflected signal, it is possible to calculate the distance to the impedance inhomogeneity (fault). Reflections from the probe pulse are observed on a range-scaled screen, and by their form can be determined the nature of inhomogeneity.
Inhomogeneities of the impedance are the result of a violation of the cable production technology, as well as a consequence of mechanical and electrical damage during the construction and operation of the cable. Inhomogeneity also occurs in the points where any devices are connected to the cable line (coupling, branch, cable splice/joint, Pupin coil, etc.), or in points of faults (open circuit, short circuit, wetting of the cable core, leakage to earth, leakage to an adjacent wire, broken pairs, etc.). The TDR method makes it possible to see multiple inhomogeneities, both discrete and distributed, depending on the ratio of their length and the minimum wavelength of the probe pulse spectrum.

TDR RI-407 reflectogram examples:

m250pw10a1g0U1
The reflectogram of the cable taken with the TDR RI-407, pulse width is 10 ns, the pulse amplitude U1 (18 V). The inhomogeneities at the far end of the cable are practically invisible against the background of noise.
m250pw10a1g0U2
The reflectogram of the cable taken with the TDR RI-407, the pulse width is 10 ns, the INCREASED amplitude U2 (86V). The inhomogeneities at the far end of the cable are well visible against the background of noise.
m250pw10a1g0U2_zoom
Detailed view of the trace at the far end of the cable using a horizontal zoom.

Arc Reflection Method (ARM)

in combination with a High-Voltage Pulse Generator (HVPG), for example ADG-200-2 “STINGRAY-M”, allows to detect High-Resistance faults (> 1 kOhm) with the accuracy of the TDR method.

You can read more about this method at the link:

Arc Reflection Method (ARM) for high-resistance faults prelocation

!407+ГВИ_shema_realizacii_impulsno_dugovogo_ADG_metoda копия копия

Localization of high-resistance faults at the site of a defect is usually difficult when using a low-voltage pulse measurement method. One of the ways to localize such defects on power cables is the Arc Reflection Method (ARM).

The essence of the ARM method is that a short-term electric arc is created (with the help of High-Voltage Pulse Generator ) at the place of cable damage. A burning electric arc has a low resistance, so it is well detected by an TDR.

The method does not require preliminary burning of the insulation and is especially effective when working on cables with a polyethylene sheath.

An example of reflectogram of a cable line obtained by a ARM method:

m500p50a1g0U2_ARC
Localization of high-resistance faults by the ARM method of the TDR RI-407. The reflectogram of the cable obtained by the TDR method is displayed in green color. We see the whole cable to the end, the high-resistance fault is not determined. The reflectogram recorded by the reflectometer during a short-term breakdown in the point of the fault is displayed in blue color. Signal is reflected with negative polarity from low arc-resistance.

Impulse Current Method (ICM), DECAY  travelling wave method

in combination with a High-Voltage Pulse Generator (HVPG), for example ADG-200-2 “STINGRAY-M”, it allows to determine the location of high-resistance defects in cases where the fault is distributed in nature and electrical breakdown occurs without ARC ignition (respectively, ARM is not applicable)

You can read more about this method at the link:

!407+гви_shema_realizacii_metoda_kolebatelnogo_razryada _ГВИ-копия

Impulse Current Method (ICM), DECAY  travelling wave method for determining high resistance faults

Locating faults caused by a floating breakdown of insulation is usually difficult when using a low-voltage TDR measurement method. One of the ways to localize such defects on power cables is the oscillatory discharge method (ICM / Decay).

The method of oscillatory discharge (wave) is based on measuring the duration of the period of the oscillatory process that occurs during the breakdown of a charged cable.

To create an oscillatory process in the cable, with the help of HVPG, the voltage in the cable is smoothly raised to breakdown, but not higher than the value determined by the norms of preventive tests, or with the help of HVPG, the built-in high-voltage capacitor is charged and then discharged into the cable.

The reflectometer in this case acts as an oscilloscope that records the oscillatory process in the cable (using a current sensor – ICM method or voltage sensor – Decay method).

An insulation defect causes a breakdown at the place of damage, a and an oscillatory discharge occurs in the cable. Knowing the speed of propagation of the electromagnetic wave along the line and the period of the oscillatory process, it is possible to calculate the distance to the breakdown:

x(v,t)
X is the distance to the floating breakdown, m
v – velocity of electromagnetic wave propagation in the cable , m / µs
tpp – time of the period of the oscillatory process, µs
s – speed of light equal to 299.8 m / µs
KU – the value of the shortening factor
m1000g160_WAV
Localization of high-resistance faults by the TDR RI-407 by the Impulse Current Method (ICM). The distance to the high-resistance defect is defined as the period of the oscillatory process arising during the breakdown in the cable.
Specs

TDR RI-407 cable fault locator technical specifications

 Specifications

 
Measurement modes
  • Reflectometry  (TDR)
  • Arc-Reflection Method  (ARM)
  • Impulse Current Method (ICM)
  • Voltage Decay (Decay)
Displaycolor TFT 10” (800х600 px)
Distance range (time delay)from  0  to  256000 m  (from 0 to 2560 us)
Measurement subranges 0 – 62.5 m (0 – 0.625 μs)
0 – 125 m (0 – 1.25 μs)
0 – 250 m (0 – 2.5 μs)
0 – 500 m (0 – 5 μs)
0 – 1000 m (0 – 10 μs)
0 – 2000 m (0 – 20 μs)
0 – 4000 m (0 – 40 μs)
0 – 8000 m (0 – 80 μs)
0 – 16000 m (0 – 160 μs
0 – 32000 m (0 – 320 μs)
0 – 64000 m (0 – 640 μs)
0 – 128000 m (0 – 1280 μs)
0 – 256000 m (0 – 2560 μs)
Distance measurement error 0.025% to 0.2%     from subrange
Effective sample rate 800 MHz
Output impedance 75 Ohm
Probing pulse duration 10 ns to 100 μs
Amplitude of the probing pulse   (per open circuit)
  • U1 – not less than 18 V (not less than 9 V per load)
  • U2 – not less than 86 V   (not less than 43 V per load)
Receiving sensitivity no worse than 10 mV
Overlapped attenuation range not less than 73   dB
Shortening factor setting range from 1.000 to 3.000, with a step of 0.001
Time delay adjustment range (pulse-arc method) from 0 to 50 ms, in 0.2 ms increments
Synchronization (pulse-arc method)
  • measurement input
  • TRIG input
Amplitude Sync (Wave Method) -165 to +165 V, in 2 V steps
Nonvolatile memory size for traces at least 1000 traces
PC interface via external USB flash drive
Continuous battery life at least 6 hours
Continuous operation time via network adapter unlimited
Dimensions 152х339х295 mm
Operating temperature range -20 ° C to + 40 ° C
Instrument weight with battery no more than 4 kg
Features

Features

  • TDR RI-407 implements most effective and careful fault pre-location methods in the power cable : TDR, ARM, ICM, voltage Decay;
  • Color 10.4″ TFT-display with a resolution of 800×600 pixels;
  • Wide distance range – 1m … 256 km;
  • Powerful probing pulse (up to U2 = 86 V on open circuit ) for operation on long cable lines or cable lines with high attenuation;
  • Wide range of adjustable Pulse Width 10 ns …100 us;
  • Extremely short dead-zone – 1m;
  • Two-cursor measuring system;
  • High measurement accuracy – up to 0.025%;
  • Multiple Zoom feature – the possibility of a detailed view of any part of the reflectogram;
  • Suppression of asynchronous interference – Averaging feature;
  • Adjustable Digital Low-Pass Filter – for synchronous interference suppression;
  • “Difference” feature – the mode of point-by-point subtraction of traces, which allows displaying only differences;
  • “Capture” feature – the mode of detecting blinking faults – irregularities that are not constant in time;
  • expandable built-in Сables Library;
  • nonvolatile memory – at least 1000 detailed waveforms with the possibility of simultaneous display of up to 3 of them for comparison;
  • the ability to adjust VoP and Сursors positions in the reflectograms already recorded in the memory with subsequent rewriting;
  • “Screenshot” function that allows quickly save screenshot of the device in JPG file with date/time stamp; images are recorded to an external storage device simultaneously with the trace files and can be read by any graphic or text editor, which can be useful when drawing up reports;
  • USB port for quick and convenient data exchange with a PC;
  • expandable firmware functionality – easy and safe firmware update;
Delivery

TDR RI-407 cable fault locator delivery contents:

Delivery contents

 
Cable Fault Locator TDR RI-4071 pc.
Power adapter DC 12V 1 pc.
Connection cable 75 Ohm, 3 m,  BNC.M – «crocodile» clips with working width 25.4 mm1 pc.
Connection cable 75 Ohm, 1 m,  BNC.M-BNC.M2 pcs.
User Manual TDR RI-4071 pc.
CD with software and documentation1 pc.
Accessory bag1 pc.

Additional equipment

Arc Discharge Generator ADG-200-2 (10 kV, 200 J, 17kg)
Voltage protection unit UP-1 for operation on cables under voltage up to 380 V;
Extension cable   5 m, 75 Ohm, BNC.M-BNC.F
Connecting cable 1.5 m, 75 Ohm, BNC.M-crocodiles 25.4   mm
Connecting cable     0.1 m, 75 Ohm, & nbsp; BNC.M-crocodiles
Adapter BNC.M – terminals
USB-Flash drive
Media

Opereating cable fault locator TDR RI-407

TDR RI-407 & ADG-200-2 Part 1 Overview, Low-Resistance cable fault prelocating with TDR
TDR RI-407 & ADG-200-2 Part 2 High-Resistance cable fault prelocating with ARM, ICM
TDR method example (short spark gap at the end of the cable line)
Arc Reflection Method (ARM) — breakdown at the spark gap at the end of the cable line
Arc Reflection Method (ARM) — breakdown at the spark gap at the end of the cable line, (accelerated shooting 400 frames / sec)
Impulse Current Method (ICM) method – breakdown at the spark gap at the end of the cable line
Impulse Current Method (ICM) method – breakdown at the spark gap at the end of the cable line, (accelerated shooting 400 frames / sec)
Certificatie

TDR RI-407 cable fault locator certificates:

Russian Federation : The device is certified by the State Standard of Russia and entered in the State Register under No. 61483-15. & nbsp; Certificate of type approval of measuring instruments RU.C.27.004A. # 59677.

Republic of Kazakhstan : The device is registered in the register of the State System for Ensuring the Uniformity of Measuring Instruments of the Republic of Kazakhstan under No. KZ.02.03.07316-2016 / 61483-15. Certificate No. 13246 on the type recognition of measuring instruments.

Republic of Belarus : The device is registered in the State Register of Measuring Instruments of the Republic of & nbsp; Belarus under No. RB 03 16 7045 19. Certificate No. 12608 on & nbsp; type approval of measuring instruments.