The DURESCA Busbar System
The conductor is made up of a cylindrical aluminium alloy type EN AW-6101B T7, or of an electrolytic copper. The insulation lies directly on the conductor and consists of wrapped paper dried under vacuum and impregnated with EPOXY resin. Conductive grading layers are embedded during the wrapping in the insulation for the field control. An earth screen in copper of min. 50 mm2 is embedded in the insulation. It is, in case of an exceptional failure, the best protection for the people and the installation. On the whole lenght of the bar, the surface of the insulation is covered by a protection tube. This tube provides an effective barrier against moisture ingress and an good protection against shocks.
The single bars are manufactured in lengths up to 10 meters. For longer bus runs or by tight place conditions where only short pieces can be installed, the single busbars are joined together on site. The joints are flexible or rigid and are also electrically shielded by insulating sleeve. The single bars are custom made and their installation consists mainly of the easy assembly of standard components. The adjustment of the length occurs in the insulating sleeves through the use of flexible connectors.
Testing / Quality assurance each single bar is subject to a routine test schedule which consists of:
measuring of capacitance, tan delta, partial discharges and 50 Hz withstand voltage test. Each GIS connection part is additionally pressure tested to check its sealing properties.
- Protection class Busbars IP 67. Cylinder and protection boxes IP 64 as standard, IP 68 on request.
- Allowed ambient air temperature –40°C up to +40°C (other ranges on request)
Type DURESCA® DE
The insulation body is protected by a high quality (PA12) corrugated tube in polyamide. Furthermore, the corrugation provides an increase of the creepage distance on the end of the busbar. The selected quality authorizes as well an indoor or outdoor use.
The good behaviour in the severe climatic conditions was checked according to the ASTM Cd 2565 standard and tested in an independant laboratory. MGC has used this type of protection tube for more than 20 years.
Description of DURESCA® busbars, type DE:
- Indoor/indoor, outdoor/indoor or outdoor/outdoor service
- Solid, separate and fully isolated phase bus
- Earth screen in copper, embedded in the insulation and designed for an exceptional fault current of 8 kA /1s
- High short-circuit capability
- Partial discharge free operation
- Factory tested
- Custom engineered for each individual installation
- Compact design with reduced bending radius
- Easy and fast installation
- Without maintenance
Type DURESCA® DG
In case of particular requirement in an heavely polluted area the polyamid corrugated protection tube could be replaced by one in CrNisteel or Aluminium.