Double Break Disconnectors
Construction
The Double break Disconnectors are of simple construction centre post-rotating breaks at both ends. The three-column disconnectors are mounted on a fabricated steel frame and rotating post is supported by two ball bearings to ensure smooth operation.
Main Contact
The main contact consists of two fixed contacts mounted on support insulators on both end and one moving blade mounting on the rotating insulator at the centre. The fixed contacts are made out of hard-drawn electrolytic copper duly silver plated and are of reverse design supported by stainless steel springs. The main blade is equipped with a turn and twist mechanism that ensures reliable contact pressure, smooth closing and opening of the switch and self-wiping which makes the disconnector suitable for installation in areas with severe climatic conditions. Depending on the voltage ratings, anti-corona shields shall be provided. The dead -center interlocking of operating mechanisms ensures there are no inadvertent changes in the open or close switching position even under extreme external conditions
Earthing Switch
The earthing switch can be built onto the right-hand side and/or left-hand side of the disconnector. The earthing blade is made out of an aluminum tube and is equipped with silver-plated copper contacts.
Operating Mechanism
The disconnector and/or earthing switch can be of individual pole or three pole type and is operated by means of motor operated mechanism or manual operating mechanism. In case of individual pole motor operation, the three poles can be operated electrically through a master and follower circuit and in case of three pole operated switch, the poles are interconnected by means of adjustable coupling pipes. The drive mechanism also housed the auxiliary contacts for position indication and interlocking.
Testing
The disconnector and earthing switches are designed, and type tested in accordance with the latest IEC specifications. Quality Management systems are being maintained according to ISO:9001-2008.
Installation & Maintenance
The disconnectors and earthing switches are pre-assembled and adjusted. The construction is designed so that all disconnectors can be installed and adjusted at the site without any special tools. Clear instruction manual and assembly drawing ensure hassle-free installation. SMC disconnectors are virtually maintenance-free. However, to ensure a long and trouble-free service period, a visual inspection of contacts and bearing points can be carried out at intervals
Testing
The disconnector and earthing switches are designed, and type tested in accordance with the latest IEC specifications. Quality Management systems are being maintained according to ISO:9001-2008.
Installation & Maintenance
The disconnectors and earthing switches are pre-assembled and adjusted. The construction is designed so that all disconnectors can be installed and adjusted at the site without any special tools. Clear instruction manual and assembly drawing ensure hassle-free installation. SMC Disconnectors are virtually maintenance free. However, to ensure a long and trouble-free service period, a visual inspection of contacts and bearing points can be carried out at intervals.
Centre Break Disconnectors
Construction
Centre break disconnectors are of simple construction, with both ends rotating and breaks at the centre. The two-column disconnectors are mounted on a fabricated steel frame and rotating posts are supported by two ball bearings to ensure smooth operation.
Main Contact
The main contact consists of a U- shaped tube, in which the main contacts and the rotating contacts are installed. They are made of copper, with a silver-plated surface. Each contact finger is provided with stainless steel springs to ensure reliable contact pressure. The contacts are self-cleansing which makes the disconnector suitable for installation in areas with severe climatic conditions. Depending on the voltage rating, anti-corona shields will be provided. The dead -center interlocking of operating mechanisms ensures there are no inadvertent changes in the open or close switching position even under extreme external conditions.
Earthing Switch
Earthing switch can be built onto the right-hand side and/or left-hand side of the disconnector. The earthing blade is made out of an aluminum tube provided with silver-plated copper contacts.
Operating Mechanism
The drive mechanism is enclosed in aluminum or stainless-steel cubicles with a robust gear mechanism to endure more than 10,000 operations. The operating mechanism also houses the auxiliary contacts for position indication and interlocking.
