Scheme R

This scheme is used to prevent the paralleling of lines #1,2,3 through a common tie bus.

Initial Conditions: Line #1 feeds load #1 through breaker #1; Line #2 feeds load #2 through breaker #2; Line #3 feeds load #3 through breaker #3. Tie breakers #1,2,3 are locked open with no keys present. Breakers #1,2,3 are closed with their respective keys "A & D", "B & D" and "C & D" captive.

Switching Scenario 1: Feeding load #1 from Line #2(#3): Open and lock breaker #1 thereby removing the "A & D" keys. Use the "A" key to unlock and close Tie breaker #1; Use the D key to close tie breaker #2(#3). Reverse to restore the initial conditions.

Switching scenario X: Congruous to above; i.e Feeding load #3 from Line #1(#2); Feeding load #2 from Line #1(#3).

Note: The tie breaker key interlocks are dual combinated and can accept two independent keys.

Additional Schemes:
A / A1 / B / B1 / C / D / E / F / G / H / H1 / H2 / K / L / M / N / O / P / R / U.P.S. System / Capacitor Bank Access Scheme