are to operate essentially as they were designed to

[france3]

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are to operate essentially as they were designed to ?

The bus system discussed is shown in Figure 13. The bus loads include several high inertia fan motors that dominate the voltage charactistic3 during the open circuit period. A detailed list of the bus loads is shown in Figure 13.
The existing auxiliary bus transfer capabilities were left in service and are to operate essentially as they were designed to before the TLC was installed. The TLC is installed so that it can be isolated from breaker control circuits by the operation of a cutoff switch (CO./TLC). The cutoff switch contacts are connected to allow the existing scheme to operate independently of the cutoff switch position.

[Тимурыч]

....и должны функционировать в соответствии с проектными характеристиками до установки TLC