Wire and cable fault location equipment has rised as a
result of cable applications, using the progress and development of electronic
technology, after having a century of changes, the key still but looks Nisshin.
As a result of few cable systems failure, positioning experience accumulate
very slow. Using the use of automation, technology, the instrument has made
substantial progress. Power Cable Fault Locator is utilized to do this work.
There are four steps of cable fault location process.
(1)CABLE FAULT TYPE JUDGMENT
Should first
serious take a look at the failure of cable throughout, fully understand the
faulty cable, and detailed records, which will help find fault faster.
Positioning method and sort of cable fault. Judgment cable fault type enables
you to measure the insulation resistance or DC voltage test. Shaking table or
digital megger relative measurement fault cable and white, and metal outer
sheath-ground insulation resistance value. Point of failure the measured worth
of the insulation resistance measuring voltage, the condition of the environment,
sometimes values ??vary greatly. At different voltages, to see the changes over
time, the insulation resistance of the fault point, combined with the
characteristics from the cable and laying path, so that you can interpret many
of information, as an example, the sort of failure as well as the possible
positions.
(2)FAULT PRETARGETING
Bridge method and
wave reflection way of the the pretargeting two main means. The proportion of
resistance on the point of failure on sides of the cable core resistance and
instrument constitutes the Murray Bridge, can be a traditional classic cable
fault location. Positioning the bridge equipment low cost, simple operation,
and had widespread use. Traditional positioning from the bridge, the rated
output voltage only 500V, unable to locate high impedance fault. The big
quantity of applications, cross-linked polyethylene cable breakdown is
difficult to form the conductive zone breakdown point resistance is high, or
even have the ability to withstand our prime voltage was flashover type
breakdown. Using the positioning of the popularity of wave reflection method,
the method of application of the bridge gradually reduce, not known towards the
new cable users.
(3)PATH DETECTION
The precise
positioning ahead of the point of failure, you need to know the position and
direction of the underground cable, the relevant details are often inaccurate,
not even. With a dedicated path analyzer measured to find the position and
direction of the underground cable. Path analyzer uses the audio induction
method to appraise the cable path. The audio generator for the the measured
cable input audio signal current on the headend, the receiver is received on a
lawn fault cable generates a magnetic signal to its path and depth measurement.
(4)ACCURATELY FIXED
Depending about
the kind of fault, there are various ways and instruments for pinpointing.
Cable Fault Locator is a necessity. Fault Location in Power Cable is designed
to locate cable faults, pinpointing the fault location, route tracing, cable
identification, voltage withstand make sure cable information management. It
could locate all kinds of cable faults for many voltage level cables, including
open circuit, short circuit, low insulation, high insulation and flashover
faults, etc. Most power cables were buried underground, invisible, and
unrealistic, with modern new power cable fault testing equipment, it may
discover the fault point quickly, solve problems immediately and restore power
source.