Synchronizer

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Either phase matching or slip frequency synchronizing may be selected. Phase matching provides

rapid synchronizing for critical standby power applications. Slip frequency synchronizing ensures that

the initial flow of power will be either out of the local system (export) or into the local system (import),

depending on whether a positive or negative slip is chosen. For both synchronizing methods, the

MSLC-2 uses actual slip frequency and breaker delay values to anticipate an adjustable minimum

phase difference between the utility and the local bus. Additional synchronizer functions include volt

age matching, time delayed automatic multi-shot reclosing, auto-resynchronizing and a synchronizer

timeout alarm. Each of these features may be enabled or disabled during setup.

The MSLC-2 control provides a safe automatic dead bus closure function. Deadbus closing permission

is granted to only one DSLC-2 or MSLC-2 control in the whole system through locking techniques done

over the communications network.

The MSLC-2. configured as tie-breaker control, allows selecting different closure modes or all modes:

• Alive bus A -> dead bus B

• Dead bus A -> dead bus B

• Alive bus B -> dead bus A