The document summarizes the replacement of a failed SF6 breaker unit in a 115kV substation in Kuwait using live line work techniques. A team from ELESA SA and IMCO Engineering conducted the replacement, which involved bypassing the circuit switcher, replacing the faulty breaker unit, and installing new jumpers while the line was still live. This allowed the job to be done without an expensive shutdown and avoided losses of $1 million from deferred oil production. The successful project set a precedent for introducing live line work in substations in Kuwait.

1. OBJETIVE:
The objective is to present the replacement and
re-connection job (doing Live Line Work) of an
SF6 breaker unit, from S&C, in the 115 kW & 20
MW substation of Join Operations, in SUG oil
field, Kuwait.
DEVELOPMENT:
After more than 5 years working for different
utilities, ELESA S.A., which is a company
dedicated to maintenance, consulting and Live
Line training in both local and international
levels, did contact with IMCO company which
carries out construction and maintenance
projects in Kuwait and other Middle East
countries. An agreement between companies
was established, that allow us to complement
and enrich ourselves.
In this opportunity the challenge was to replace
an SF6 breaker unit, from S&C, that was failed
due to gas leakage.
It was located in a radial substation that supplies
20 MW to the high production SUG Oil Field.
In the emergency, and in order to restore the
power supply, the complete circuit-switcher was
by-passed, and a shutdown was programmed to
replace the interrupter.
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COMISIÓN DE INTEGRACIÓN ENERGÉTICA REGIONAL
REPLACEMENT OF CIRCUIT-SWITCHER IN 115 KV SUBSTATION
Author/s: Carlos Arata
Company: ELESA International S.A.
Author/s: Jalal Mohesen – Pablo Jurado
Company: IMCO Engineering & Construction Co.
COMPANY INFORMATION
ELESA SA
Telephone: (54) 93461 512966
E-mail: info@elesa.com.ar
c.arata@elesa.com.ar
IMCO
Address: P.O. Box 9309 Ahmadi, Kuwait
Zip Cod: 61004
Telephone: (965) 2398 1661
Fax: (965) 2398 4708
E-Mail: pjurado@imcokw.com
jmohsen@imcokw.com
KEY-WORDS: Uninterrupted production
– Innovation – Complementation
between companies
COMPANY: ELESA SA - IMCO Engineering & Construction Co.
COUNTRY: Kuwait
Type: Technical Paper
Kuwait, May 2011.

2. By-passed circuit-switcher
By chance I was giving training and refreshment
course to the Live Line crews when I knew about
the equipment failure. It seems to me and
interesting challenge, and us when to see the
substation.
The job to be carried out was similar to others
that we have already made at the 66 kV
substation of EDEN Company in Argentina.
But the two main differences were, by one side,
the unavailability in Kuwait of the equipment that
ELESA has for substation jobs, and by the other
side, the generous safety distances in the
substation portal structure.
After discussing the possibility of doing the job
by applying Live Line Work, the scheduled
shutdown was suspended.
The similar jobs previously done consisted in by-
passing measurement and operation
equipments, for maintenance, which avoided the
replacement of them, thing that made no sense
at that time. We did these types of jobs since
2002, when we finished the construction of the
prototype for working in substations.
By-pass 66 kV Substation, EDEN, October
2003
Steps of the task
Basically the Live Line Work in this case
consisted of 4 main steps which are:
1) Replacement of the failed breaker unit
2) Circuit-Switcher-to-Surge Arrester
jumpers installation
3) Circuit-Switcher-to-Line jumpers
installation
4) Removal of the temporary by-pass
jumpers and old jumpers from line-to-
circuit switcher (having close the
circuit-switcher previously)
1) Replacement of failed breaker
unit
The failed unit was the middle one, which is the
most difficult to work on, for all steps.
Two Class A, approved to work up to 132 kV,
insulated lift, were used to do the job.
We had to study carefully the safety distance to
work on the installation.
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COMISIÓN DE INTEGRACIÓN ENERGÉTICA REGIONAL

3. General view and distances
The lift trucks that we used have two articulated
booms, with the upper one telescopic (Class A).
These features make them quite versatile to
work in complicated installations, giving as good
flexibility to find the most suitable position.
Besides this, they have a material handling
system with 700 lbs capacity in the worst
condition. We used this feature to remove the
failed unit and to install the new one (Step 1, see
the following picture)
Installing the new SF6 unit
2) Transformer side jumper
installation
One again here the more complicated to
install was the central phase jumper, to
which we had access by positioning the
bucket between the insulators of the circuit-
switcher. In order to connect the circuit-
breaker with the jumpers on the surge
arrester, and due to there wasn’t enough
room to work by barehand method, we
installed a jumper by using hotsticks, made
of extra-flexible cooper conductor (120 mm²)
mechanically reinforced with an extra-
flexible steel wire, and with two duckbill
clamps of 400 A capacity each one, which
was much more than we need, an also this
feature allowed us to handle the jumper by
using two sticks, therefore improving the
safety at the work.
3) Circuit-switcher-to-line
jumpers installation
The jumpers to be installed were 6 m long. First
they were installed in the pedestal insulator of
the open switch, and then in the lug of the
tension clamp.
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4. Leaving the lug free
But as n the lug there was the existing
permanent jumper still connected forming a loop
in which the by-pass was installed, before
connecting the new jumper a piece of the old
jumper had to be removed.
In this case, due to the distances at the portal
side are wide enough there is no difference in
starting to work in the middle phase or in the
lateral ones.
Going up with the new jumper
The new jumper was attached first to the main
conductor using a short flexible jumper, before
connecting both lugs. This short jumper took the
capacitive load of the new jumper and
mechanically insures the connection to avoid an
unexpected drop of the jumper.
Fixing the new jumper to the dead-end
terminal
4) Removal of the temporary
by-pass jumpers and old
jumpers from line-to-circuit
switcher (having closed the
circuit-switcher previously)
Once the new permanent jumpers have been
connected, it was missing to remove the
temporary by-pass jumpers installed during the
emergency, and the original jumpers from line-
to-switch that were tied back forming a loop.
This task was done working with simultaneously
with two insulated lifts, due to they were
available as well as the necessary personnel.
The synchronization of the task was in charge of
the supervisor on ground, and the good
communication was insured by using walkie-
talkies.
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5. The operation of disconnection of the by-pass
was made with hotsticks according to the
fundamentals of the barehand method, in order
to eliminate any possibility of one lineman to be
in series with the circuit.
Preparation to disconnect the by-pass
The by-pass jumper to be removed was still
attached to the old piece of jumper by an
insulated rope, which is lately removed, while the
other crew picked-up the by-pass jumper.
The other crew removes the by-pass jumper
Removal of the by-pass jumper with two crews
working together
Having completed the above mentioned step, the
last thing to do was to remove the old permanent
jumpers, which were cut in three pieces to avoid
they were opened due to their elastic memory
while removing, since, we must remember, these
jumpers were 6 m long.
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COMISIÓN DE INTEGRACIÓN ENERGÉTICA REGIONAL

6. CONCLUSIONS
The technician that was sent by S&C (the
manufacturer of the equipment to be replaced)
didn’t know about the possibility to do this job
Live, although it could done in a safe way and
according to the previously developed
procedure.
The execution of this Live Line Work avoided a
costly shutdown to the oil company, that was
planned to be of at least 8 hours with a loss of
approximately u$s 1 million in differed oil.
In addition the execution of this job is an
important precedent to introduce the concept of
Live Line Work in Substations that had never
been considered before in this country.
LESSON LERNT
The conjunction of qualified personnel, and
necessary equipment together with the team
work for the development of the procedure and
the explanation of it to the people who make the
decisions (which showed reluctant at the
beginning), allowed the completion of a this kind
of job for the first time in the country and
probably in all Gulf area.
RECOMENDATION
Start thinking that a Live Line Work in
Substation is possible until the contrary is
demonstrated, don’t think in the reverse way.
Site work team
ELESA SA
Carlos Arata
IMCO
Pablo Jurado
Khaled Alí Manssur
Mohamed Abou Elenin
Nabil Abd el Mohesen
Ahmed Sultan Mohamed
Mohamed Abdul Ghani
Mohamed Khalaf Shakoor
Rheda Mohamed
V. Perumal
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COMISIÓN DE INTEGRACIÓN ENERGÉTICA REGIONAL

7. CONCLUSIONS
The technician that was sent by S&C (the
manufacturer of the equipment to be replaced)
didn’t know about the possibility to do this job
Live, although it could done in a safe way and
according to the previously developed
procedure.
The execution of this Live Line Work avoided a
costly shutdown to the oil company, that was
planned to be of at least 8 hours with a loss of
approximately u$s 1 million in differed oil.
In addition the execution of this job is an
important precedent to introduce the concept of
Live Line Work in Substations that had never
been considered before in this country.
LESSON LERNT
The conjunction of qualified personnel, and
necessary equipment together with the team
work for the development of the procedure and
the explanation of it to the people who make the
decisions (which showed reluctant at the
beginning), allowed the completion of a this kind
of job for the first time in the country and
probably in all Gulf area.
RECOMENDATION
Start thinking that a Live Line Work in
Substation is possible until the contrary is
demonstrated, don’t think in the reverse way.
Site work team
ELESA SA
Carlos Arata
IMCO
Pablo Jurado
Khaled Alí Manssur
Mohamed Abou Elenin
Nabil Abd el Mohesen
Ahmed Sultan Mohamed
Mohamed Abdul Ghani
Mohamed Khalaf Shakoor
Rheda Mohamed
V. Perumal
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COMISIÓN DE INTEGRACIÓN ENERGÉTICA REGIONAL