Cable Fault Location & Detection On Live Power Distribution Systems (Network Rail Approved)

Published 29 Apr 2019

Cable Fault Location & Detection On Live Power Distribution Systems (Network Rail Approved)

Locating Cable Faults

  • uploaded by Chris Dodds - Thorne & Derrick Sales & Marketing Manager

Fault locator to offer proactive monitoring, detection and location of both insulator and conductor faults on live low voltage unearthed power distribution systems.

CableGuardian by Viper Innovations allows for quick electrical fault location on rail signalling power systems and displays them clearly on a user-friendly interface.

The cable fault locator traces both insulation and conductor faults as multiple units can be connected can isolating insulation faults to a section of cable and pinpointing the location of the conductor fault.

CableGuardian has the ability to send notifications via e-mail, SMS, and even voice call for serious faults such as open circuits, short circuits and intermittent faults reducing the time spent trying to locate the fault due to Spread Spectrum Time Domain Reflectometry (SSTDR).

The modular nature of CableGuardian allows for remote compliance with the Network Rail M003 Maintenance and Testing requirements.

The cable fault detector is suitable for the following locations including rail industry signalling power systems, legacy system equipment upgrades and electrical power distribution systems with ungrounded (Isolation Terra) AC pairs at working low voltages of up to 750V on Network Rail infrastructure.

CableGuardian - Cable Fault Location & Detection

CableGuardian – Cable Fault Location & Detection


Cable Fault Location & Detection

Features & Benefits

  • Distributed and intelligent infrastructure for cable health monitoring
  • Integrity alarms and fault information direct to asset stakeholders
  • Helps to avoid injury and reduce downtime through early fault detection and cable location
  • Analytics facilitate proactive, rather than reactive, maintenance
  • Enables faster and more accurate repair, minimising service outage
  • Permits a move from a frequency based inspection regime to one driven by actual asset condition and performance
  • Immediately locates and alarms the first cut during cable theft
  • Enables compliance with the requirements of the Network Rail standard for Insulation Monitoring NR/L2/SIGELP/27725
  • Fault tolerance built in – each CableGuardian node is a “slave” to the “Supervisor and Analytics System” – no “Master” node required
  • Automatic configuration of CableGuardian nodes added or removed from the system
  • Inbuilt GPS for auto-location on installation (option)
  • Provides “data hub” for interfacing with IOT nodes such as weather centres and IP enabled cameras

CABLEGUARDIAN – Product specification

Input Power Supply (wiring options):110V AC 47/63Hz “domestic supply”
230V AC 47/63Hz “domestic supply”
Direct from Line Supply being
Line Supply Conditions:Voltage: 300V to 750V 1
Frequency: 47Hz to 63Hz
Capacitance: Up to 500μF
Power Consumption:25W typical
30W maximum
Earth Connections:“Reference Earth” and “Protective Earth”
wired connections via cable gland to
internal Earth terminal
Communications Options:Ethernet 10/100 Base-Tx
3G/4G Cellular (SIM embedded)
Fibre Optic 100Base-FX, LC Duplex,
1300nm Multimode
Service Port (setup & configuration):USB 2.0 Type A
IR Current Loop (option):Output: 4-20mA @ ±1%
(various modes available)
Front Panel Indicators:Input supply on
Internal power on
Line open / short circuit alarm
IR pre-alarm (Warning)
IR alarm (Fault)
IC pre-alarm (Warning)
IC alarm (Fault)
Downstream IR alarm
GPS & Cellular Aerial (option):External mounted, dual function (IP67)
Network Insulation Resistance (IR):1kΩto 1GΩ@
Directional Insulation Resistance:
(via External Coil)
1kΩto 10MΩ@ Network IC dependent
Response Value (Alarms) 2:1kΩto 10MΩ
Network Insulation Capacitance (IC):0.1μF to 150μF @±25% ±0.05μF
Directional Insulation Capacitance:
(via External Coil)
0.1μF to 80μF @ Network IR dependent
Line Voltage (True RMS):Up to 750V1 AC @±3% ±5V
Line Current (True RMS):
(via External Coil)
Up to 120A @±1%
Line Frequency:47Hz to 63Hz @±1% ±0.5Hz
Line Power (True RMS):±3% ±5W
Line Power Factor:-1 to +1
Polarisation Index (PI):In accordance with IEEE-43-2000
Dielectric Absorption Ratio (DAR):In accordance with IEEE-43-2000
Conductor Short/Open Circuit:Located to 98% accuracy by distance
Intermittent Conductor Faults:Duration >100mS
Operating Temperature Range:-25 °C to +70 °C (-13 °F to 158 °F)
Storage Temperature Range:-40 °C to +85 °C (-40 °F to 185 °F)
Relative Humidity:Up to 100%
Design Life:Minimum 15 years operation
Climatic Conditions:‘Category T1 environment’ as defined in BS EN 50125-3
Solar Radiation:1120 W/m2 as defined in BS EN 50125-3
Shock and Vibration:‘Outside the track’ as defined in BS EN 50125-3
Dimensions:See diagram below (in millimetres [inches])
Mounting:See diagram below (M6 fixings)
Construction and Assembly:In accordance with BS EN 61439-2
and BS 7671
Ingress Protection:IP54 as defined in BS EN 60529
Fire Protection:Category F1 as defined in
BS EN 50125-2
Product Standards
Safety: BS EN 61010-1:Overvoltage Category III (110/230V Mains & 750V 1 Line)
Pollution degree 2
BS EN 61010-2-030:Measurement Category III
Electro-Magnetic Compatibility:In accordance with BS EN 50121-5
Insulation Monitoring Device:IEC 61557-1
IEC 61557-8
Network Rail:NR/L2/SIGELP/27725
CableGuardian - Diagram

CableGuardian – Diagram

The CableGuardian system may consist of a single node or multiple nodes, depending on the  system monitoring requirements and the level of fault location granularity desired.

Data Storage & Analytics System

Data Storage & Analytics System

Rail Cable Accessories, Electrification & Installation Equipment

Thorne & Derrick stock an extensive range of 400V-33kV Rail Cable Accessories & Power Distribution Sytems including feeder pillars to contractors undertaking Low Voltage Power Distribution, HV Electrification & Substations, DC Traction & Networks, OLE and Track Feeder Cable Renewals – complete range of Network Rail PADS approved track terminations, cable joints, cable repair and connection products up to 25kV, including 3M Cold Shrink, Pfisterer CONNEX and Nexans Euromold products.

Full range of Cable Pulling Equipment & Products to ensure safe and efficient of rail cables in to cable ducts and containment infrastructure including cable troughs.

Further Reading