There are many makes and designs of air break disconnect switches each offering their own level of bounce in their operations. EHT has witnessed the operations of many types of disconnect switches and observed various level of bouncing. EHT has seen minor bouncing on high quality switches to major bouncing on poorly designed air breaks where the entire structure was oscillating significantly, causing major concerns to their users.
By using EHT’s advanced variable speed controller, the IMCC, it is possible to significantly reduce or completely remove the bouncing. By configuring and fine-tuning the system to work with a given design, the IMCC Motor Operator compensates the various forces that occur during operations like compression, resistance and slack. Compensating these forces is performed using smooth acceleration and deceleration along with precise position measurement.
Reducing the mechanical bounce on a isolator, will positively impact the lifespan of the insulators, of the structure and the air break itself. Excessive mechanical bounce will cause premature wear on the equipment and structure which may result in failure of the equipment and damage of the structure.
Furthermore, the bouncing, which occurs during the operation, causes current peaks in the motor, which has a negative impact on the lifespan of the motor. Performing smooth acceleration/deceleration and removing the irregularities in the operation will prevent these excessive current peaks and will increase the life of the motor.
Some disconnect switches do not have efficient speed reducing mechanism. These isolators will knock hard into the jaw while closing, often more than once, before rotating into the contact fingers. The knocking causes undesired vibrations on the air break switch and on the insulators. In some cases the knocking on the contact fingers reduces their lifespan.
IMCC variable speed capabilities can reduce the speed before entering the jaw eliminating virtually completely the knocking.
Extinguishes Electric Arcs Faster
On high voltage switches, large electric arcs are produced during operations. These arcs inject harsh harmonics into the grid, which tends to damage the power transformer’s solid insulation. The arc also causes premature degradation of the main contacts causing pitting on the surface.
Using the EHT’s variable speed controller can reduce the arcing time by over 50% by accelerating the operation within the arc area,
Ensures Optimal Contact Pressure
The positioning of competing motor operators is performed using cam switches. These cams are very difficult to adjust, provide poor position precision and poor reliability as they tend to misalign gradually over time. As the cams move, the closing position changes thus causing the motor operator to stop outside the optimal closing range. This alters the contact quality and causes overheating which damages the main contacts.
The IMCC solves this problem since cam switches are replaced with a robust optical positioning system that is easy to configure. This system never misaligns and assures optimal positioning/pressure at all times. This protects the contact fingers from overheating, and more importantly prevents the mechanism from stopping right in the middle of an operation due to a faulty cam alignment.
Find Out More About the IMCC Benefits
|IMCC PROVIDES MONITORING DATA||IMCC DETECTS FAILURES AND NOTIFIES||IMCC ONE SIZE FITS ALL – FROM 25KV TO 1200KV|