High Voltage Circuit Breakers

High Voltage Circuit Breakers

Electrical substations play a critical role in the National Grid as they distribute electricity to entire communities the circuit breakers at these stations routinely interrupts short circuits to prevent damage to the system they perform the same function as the circuit breaker box in your home but on a much larger scale the size of a car or even a large truck these circuit breakers troubleshoot high current situations at electrical substations this protects the grid and prevents power cuts making one of these beasts starts with a cast aluminium tank that has receptacles for bushings an assembling technician inspects each tank for dirt or floors before protective covers are placed on the bushing receptacles he installs bases for current transformers on these.

Receptacles adhesive is applied to the outside of these metal bases and squares of plastic insulation are pressed onto the blue areas with the help of an overhead lift the technician installs the two current transformers on the insulated basis these current transformers will act as sensors enabling the circuit breaker to detect short circuits in just milliseconds at another station lubricant is brushed onto the moving part of the interrupter that will break the electrical current when needed the exhaust tube that helps direct the flow of gas used to break the current is installed then the interrupter module is placed in an upright position on the floor to await the contact assembly the technician dabs thread-locking liquid into the mounting holes of the stationary contact assembly and installs a resin.

Ring in the base he goes back to the exhaust tube and inserts the stationary part into the moving one leaving the end protruding then he applies more threadlock to the assembly holes of a large tube that will shield the entire interrupter once it’s installed in the tank it will also direct the flow of interrupting gas after assembling it to the interrupter he inserts a synthetic insulating tube and the entire module is flipped over in order to work on the other end another insulating tube is installed the unit is placed on a stand to steady it as the contact assembly is inserted this is the part that opens to interrupt the electrical current the technician caps one end of the interrupter with the unit that houses the bell crank the bell crank is slid into its housing this crank will convert the rug to.

Emotion from the operating mechanism to a linear motion the crank is turned to confirm that it rotates freely the technician then clamps leads to test probes inserted in the interrupter and applies a hundred amps of current this testing device measures the interrupters resistance to the current to confirm that it’s within an acceptable range with a lift bearing the load another team member guides the interrupter module into the cast aluminium tank he bolts the bell cranks housing to the tank opening and places cylindrical electrical shields in each of the bushing receptacles he then encases the Transformers at the base with aluminium covers they’ll protect the transformer wiring from rain snow or dirt lifts now hoists the silicon rubber wrapped.

Bushings into the receptacles they’re bolted in place and the rear of the tank is capped this interrupter is now ready to be mounted to the steel support structure each high voltage circuit breaker will be equipped with three interrupters the team connects the bell cranks to the operating system in the control cabinet and they equip each Bell crank with a pressure gauge the earth the circuit breaker to the support structure with copper cables this will prevent shocks to anyone who touches it in one last test towering transformers apply high voltages to the circuit breakers and now these mechanical monsters are ready to interrupt situations before they become really shocking.