ABB Ratingen, Germany and ABB Pinetops, USA have developed a new OVR three phase reclosure for 15 to 38 kV. The new reclosure has been successfully launched in the USA.

Among other new features the vacuum interruptor is directly and fully encpasulated with cast resin. ABB selected hydrophobic Araldite® systems as insulation material to replace polyurethane.

A thermal cycle test at ABB AG, Calor Emag Medium Voltage Products, Ratingen, has shown reclosers made from hydrophobic Araldite® systems pass -80 °C without any cracks.

Helmut Leskosek, Production Plant Manager, says: “Hydrophobic Araldite® is an outstanding product. I don’t know any other epoxy material which is able to encapsulate different materials such as copper, aluminium, steel and ceramics withstanding -80°C without cracks.“

Hydrophobic Araldite® systems are Hydrophobic Cycloaliphatic Epoxies (HCEP) which are developed from standard Cycloaliphatic Epoxies (CEP), which have no fewer than 35 years of successful field service. HCEPs combine hydrophobic properties with high thermal shock resistance.

The hydrophobicity of the material reduces discharge activity, leading to less erosion and improved life expectancy. Reduced leakage currents and lower flash-over probability result in enhanced product reliability.

Many lab studies and our customers’ field experiences underline the excellent performance and reliability of hydrophobic Araldite® systems: salt fog studies (IEC 61109), wheel tests (IEC 61302), and the EDF approval test (EN26E20) confirm reduced leakage currents as well as superior tracking and erosion performance.

Hydrophobic Araldite® systems, used for outdoor insulators, bushings, switchgear parts, and instrument transformers, perform reliably in the most demanding conditions, such as salt water, high humidity, and environmental pollution.