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A simple re-arrangement of the three Circuit Breakers used in the In-Out arrangement produces a small three Circuit Breaker mesh - sometimes drawn as a triangle with a CB on each side of the triangle.
In this mesh arrangement, we only need any two of the three Circuit Breakers to be closed for full operation between all three substations. This allows for maintenance on the circuit breakers plant without disruption to the ability to generate power to the grid.
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