ACTOM High Voltage Equipment (HVE) recently introduced a vertical break (VB) 33kV isolator with composite rubber insulators for the first time, with the aim of meeting the special requirements of industrial operations faced with limited space constraints in their high voltage distribution substations.
“These units are designed mainly for heavy industry, high pollution, indoor substations such as smelters and are also suited for the railway network, where high current switches are required for use on the electric locomotive fleets,” Craig Aaron, HVE’s Senior Product Support Manager, explained.
“The VB isolator is type-tested in accordance with the international IEC 62271 standard for indoor substations. It has a much smaller footprint and is much lighter in weight than our standard horizontal double side break isolators. These units can be used as conventional isolators or customised into live to earth configuration, eliminating any operation failure of the mechanical interlocking during the operation of the isolator or earth switch, with the use of one operating mechanism.
“Once the unit is operated from the live position it automatically closes in the earth position, making it safe for operators to use. The unit is designed with self-wiping low-friction contacts for low maintenance and easy operation. The hinged part is manufactured with laminations for the current to be transferred with no sliding or touch contacts, to eliminate any unnecessary maintenance.
“In addition, all our VB units can be engineered and customised to ensure that every customer’s specific requirement is fully met.” Craig stated
HVE is currently extending the range down to 11kV and 22kV network. All VB isolators produced for the market, despite being specially customised for each individual user, will have a cost saving for the smaller footprint and having one operating mechanism to operate the live and earth switch.
HVE’s VB isolators are the only locally manufactured vertical break isolators designed for the industrial market that are currently available.
“Our 33kV VB isolator has a current carrying capacity ranging from 1600A to 2500A, making it particularly well-suited to high current heavy industrial applications,” said Craig, adding that the new product can be used for single- or multi-phase and in live-to-earth options.
HVE received its first order from a large steel smelter in Ekurhuleni shortly after giving notice of its intention to introduce the new product into the market after successfully completing type tests on the prototype for it.
The order, supplied in July, was for two 33kV 2500A 31,5kA 170BIL live-to-earth motorised units – one to replace an aging isolator in the existing smelter plant and the second for installation in a new substation that has been established to distribute power to a plant extension that is currently under construction.
