PDi WaveStar 2000A, Installation And Operation Manual

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WaveStar Static Transfer Switch 2000A 3-Pole
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Ctrl Nr: PM375118-004
7 Operational Modes
The STS has three modes of operation:
•
Normal
•
Redundant
•
Bypass
7.1 Normal Mode Operation
For normal operation, the MODE OF OPERATION toggle switch on the ROI panel should be set to
NORMAL . The STS should be left in Normal mode for all but unusual circumstances. (See Figure 16,
Redundant Operator Interface (ROI).)
In Normal mode, when the active source falls out of specification, transfer to the other power source is
automatic. There are three (3) operational choices that govern automatic transfers:
1. Transfer algorithm: choose between VSS or POG ; default= VSS . (See 9.2 Switch Settings
screen and 1.3 Transfer Process: Algorithms .)
2. Preferred Source : choose whether Source 1 or Source 2 is the preferred power source;
default= Source 1 (see Figure 13 Home screen).
3. Retransfer = Yes or No : after a transfer to the alternate source (i.e., the non-preferred
source), should the STS automatically retransfer back to preferred source when that source
is good or remain on the alternate source? Default=
Yes (See 9.2 Switch Settings screen).
7.1.1 Preferred Source
In Normal mode operation, the load is connected to the designated Preferred Source by default, as long
as the voltage and frequency of all phases of that source are within acceptable limits.
•
At initial startup, Source 1 is the default Preferred Source .
•
The Preferred Source can then be set by a logged-in user with at least operator access
privileges on the Home screen.
•
Either input power source can be designated as the Preferred Source by the setting the
Preferred Source
– 1 / 2
virtual control on the Home screen.
•
When the Preferred Source fails
—that is, when the Preferred Source goes outside acceptable
predefined limits
—the STS transfers the load to the alternate source using the chosen algorithm,
VSS or POG.
7.1.2 Retransfer Control
The Retransfer control determines whether the STS maintains an affinity for the Preferred Source
whenever it is within acceptable parameters.