Order duplicate or replacement keys

Scheme H2

This scheme is used to prevent the paralleling of any of the sources while allowing the switching of the loads to alternate sources.

Initial conditions: Utility feed A supplies load A through breaker #1 which is closed with its interlock key "A" captive. Utility feed B supplies load B through breaker #4 which is closed with its interlock key "B" captive. Breakers #2, #3, and #5 are locked open with no keys present in their respective interlocks.

Switching scenario #1: Supplying loads A and B by utility feed A(B) through breaker #1(#4) and breaker #5: Open and lock breaker #4(#1) thereby removing the "B"("A") key. Use the "B"("A") key to unlock and close breaker #5. Reverse to restore the initial condition.

Switching scenario #2: Supplying loads A and B by generator 1(2) through breaker #2(3) and breaker #5: Open and lock breaker #1(#4) thereby removing the "A"("B") key. Use the "A"("B") key to unlock and close breaker #2(#3). Open and lock breaker #4(#1) thereby removing the "B"("A") key. Use the "B"("A") key to unlock and close breaker #5. Reverse to restore the initial condition.

Switching scenario #3: Generator 1(2) supplying load A(B) through breaker #2(#3): Open and lock breaker #1(#4) thereby removing the "A"("B") key. Use the "A" ("B") key to unlock and close breaker #2(#3). Open and lock breaker #4(#1) thereby removing the "B"("A") key. Use the "B"("A") key to unlock and close breaker #3(#2). Reverse to restore the initial condition.

Note: The key interlock on breaker #5 is dual combinated and can accept either an "A" or a "B" key.

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