Page 23 - Energize April 2022

NEWS

Dry cast resin transformers have important

benefits over oil cooled transformers

egrand’s range of cast resin transformers (CRT) has been movement, is pre-equipped for the mounting of IP reinforced
designed for high-efficiency, enhanced safety and low enclosures.
Lenvironmental impact during energy distribution in diverse Legrand’s standard distribution transformers have rated power
applications. Typical installations include data centres, shopping between 100 and 3150 kVA, primary rated voltage up to 36 kV
malls, hospitals and residential buildings. CRTs are also suitable for and secondary rated voltage up to 433 V. Special transformers
photovoltaic (PV) installations and wind power, as well as offshore have rated power up to 17 000 kVA. The variable impedance level
applications, the railways, shipping and airport facilities. selection enhances the options on the fault level requirements and
These CRTs, which efficiently transfer electrical power between various tap settings are also available.
two different voltage systems, at the same frequency, ensure Accessories include thermal sensors or thermistors, electronic
reduced electricity consumption and minimal energy waste. units for temperature control and forced ventilation systems to
According to the firm’s specialists, there are important increase transformer power in temporary overloads or at high
advantages of CRT transformers over traditional oil cooled units. environmental temperatures. The company can also supply MV
The major benefits are reduced environmental impact, easy terminations for plug-in connections, surge arrester kits and anti-
installation, low maintenance requirements, flexibility in use seismic supports. Various enclosure options are available, with
and efficient operational costs. Unlike conventional oil-cooled different degrees of protection against the environment, as well as
transformers, which are highly flammable, these eco-friendly for human protection.
transformers have no risk of insulating fluid losses and are a low The synergy of products from Legrand group companies
fire hazard – even in harsh environments, such as mines and facilitates seamless integration between power distribution
chemical and petrochemical plants. The robust construction of systems, to provide the guarantee of a certified distribution system.
these units can withstand high thermal shocks and enables safe Legrand EdM cast resin transformers, Zucchini busbar trunking
operation in damp, salty and polluted environments. systems and XL³ cabinets, are manufactured according to stringent
The compact CRT system has been designed for low quality, environmental and safety specifications. Each component
maintenance requirements, which significantly reduces operational in the system ensures simplified and safe installation, with the
costs. Since no cooling fluids are necessary in the system, no versatility for any type of power application, in any environment.
oil analysis, refilling or oil purifications are needed. In addition, The company’s specialist services include enclosure building
the absence of flammable insulation liquids, the use of self- up to IP31, power factor monitoring and thermal imaging. The
extinguishing materials that are exempt of toxic gas emissions, company, with final acceptance test (FAT) and site acceptance
reduced noise levels and low electromagnetic emissions, ensure testing (SAT) capabilities, also offers complete installation and
greater safety and enhanced environmental protection in all commissioning services, as well as service level agreements.
sectors.
As cast resin units operate on the principle of air cooling and Contact Internal Sales, Legrand SA, Phone 011 444-7971,
take longer to reach operation temperature, they are particularly legrand.south-africa@legrand.co.za, www.legrand.co.za
well suited to feed loads with frequent current breakaway starting
current. Dry type cast resin units have smaller weight, size and
dimensions than oil transformers and with the absence of cooling
fluids, they can be safely installed inside commercially occupied
buildings. CTRs installed inside the building can be closer to the
loads, with the advantage of minimising connection costs and
reducing losses in the supply line. Civil costs are also lower, as there
is no need to cater for the construction of oil containment bunions.
The company’s CRTs have notable features for enhanced
efficiency and optimum safety. Rubber inserts alleviate the
transmission of vibrations between core and windings, also
reducing operating noise levels and absorbing thermal expansion of
components. Sockets on the MV side adapt the primary voltage to
the mains, which can be set with the transformer switched off. Typical installations include data centres, shopping malls, hospitals
Class F insulating material, at 155°C, allows for a temperature and residential buildings. CRTs are also suitable for photovoltaic
rise of 100°C and the epoxy resin insulation means low (PV) installations and wind power, as well as offshore applications,
maintenance. The carriage of these units, which allow safe the railways, shipping and airport facilities.

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