25 / 44
Mechanical Technology — June 2015
23
⎪
Sustainable energy and energy management
⎪
loads supplied by the alternator.
Customised high-, medium- and low-voltage
LS alternators, also available in either 50 or
60 Hz and with 4 to 24 poles, are rated from
500 kW to 25 000 kW and can be driven by
diesel or gas engines, turbines fuelled by gas
or steam, wind turbines or hydro turbines.
Also in the LS range are alternators
designed for specialised applications, for
example, in agriculture. The
robust Tractelec is a gen-
erator driven by a tractor’s
power take-off (PTO) shaft,
p r ov i d i ng
an alter-
n a t i v e
source of
energy production. This 3-phase Partner alter-
nator, which operates efficiently in demanding
farming environments, is coupled to a gearbox
with oil-cooled lubrication and an electrical
protection and distribution box.
Servicing isolated parts of Africa
According to Robertson, the company’s “highly
skilled technicians” have the expertise to as-
sist with inspections, diagnostics and repair
procedures; re-assembly, installation and
commissioning, as well as the implementation
of preventative and predictive maintenance
programmes. “It is important, especially in
isolated locations, to have a secure and efficient
power supply and a reliable support facility. For
this reason, our on-site service offering is well
received, particularly by companies in remote
areas. This field service includes inspection and
fault finding, as well as refurbishment and repair
of most types of generator.
“Where repairs are not possible on site, work
is undertaken at Vert Energy’s Johannesburg
workshop, or at a certified repair facility in
Africa.”
Apart from the company’s 24-hour assis-
tance with any emergency electro-mechanical
breakdown or repair situation, Vert Energy also
offers a customised preventive and emergency
maintenance programme, designed to minimise
the downtime of either prime power or standby
generators.
Proactive maintenance management not
only increases reliability of a system, but also
upholds consistent procedures and schedules
and maintains the factory warranty coverage of
every component. The company uses original
spare parts and accessories, according to strin-
gent OEM specifications.
Preventative maintenance for diesel engine
generators also reduces long-term operating
costs and ensures extended service life of the
system. By following diesel maintenance proce-
dures and a manufacturer’s recommendations,
the risk of failure on critical power applications
during start up is reduced.
Project successes
Vert Energy’s recent projects include the re-
winding of a 750 kVA exciter stator, in situ
below deck, on board a vessel out at sea near
Mozambique, without any interruptions to the
normal operation of the ship. Vert technicians
also installed and commissioned new generators
aboard a vessel in Namibia during a recent the
retrofit programme. These units were tested
under various loads and operating conditions
out at sea.
Other notable challenges involved the servic-
ing and maintenance of three 7 000 kVA alter-
nators at a gas turbine power plant in Nigeria
and the restored operation of a faulty 800 kVA,
525 V generator in Lesotho.
Vert Energy is the authorised sales and sup-
port partner of Leroy Somer EPG (Electric Power
Generation) products in southern Africa and
carries a full range of genuine spare parts for low
and medium voltage LS alternators. Spare parts,
such as diodes, varistors and automatic voltage
regulators (AVRs), are always readily available
and complement the full range of alternators
from 20 kVA to 2 000 kVA, which are carried
ex-stock in the Johannesburg warehouse.
Vert Energy also offers an intensive product
training programme, which entails an in-depth
look at the value of alternators used in electric
power generation.
q
The removal of the rotor from a 1 650 kVA alterna-
tor with a failed stator at Vert Energy’s Meadowdale
premises in Edenvale, Gauteng. The unit is being
stripped and checked to ensure there is no damage
to the rotor.