PDi WaveStar 2000A, Инструкция по установке и эксплуатации

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Customer Communications Connections
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5.3.3 Remote Source Select Option
Two external two dry contacts can be used to control the remote selection of the preferred source. Dry
contact closures are generally used when two UPSs supply power to the system. If the preferred UPS
goes to bypass mode, the “good” UPS becomes preferred:
•
Signal 1 (Remote Select S1) dry contact closure will make Source 1 preferred.
•
Signal 2 (Remote Select S2) dry contact closure will make Source 2 preferred.
•
If both dry contacts closures are open, the preferred source control is returned to the system
operator control panel.
Any remote control signal or closure puts
the unit into a “Retransfer=Yes" mode to ensure system
redundancy. Normally the closures are controlled by auxiliary contacts in the UPS bypass circuit
breakers. If both dry contacts close, the first input to the STS is recognized.
5.3.4 Multi-Switch Link Option (N+1 UPS)
In an N+1 UPS Configuration, there are multiple STS units, each with a preferred source fed by a
separate UPS. The alternate source on all STSs is provided by a single backup UPS.
All STS units in an N+1 UPS configuration must have Enhanced Contractor Boards and the Multi-Switch
Link Option installed, providing coordination among the STSs.
Because the backup UPS can only provide power through the STS to a single downstream load, when an
STS transfers its load to the backup UPS, the STS must signal the other STS units that it is using the
UPS. The other STS units are locked out and cannot transfer to the backup source.
An “Inhibit Transfer” alarm is signaled on each STS. The STSs are prevented from transferring until the
Preferred Source on the STS using the backup UPS returns to normal and the STS retransfers the load
back to the Preferred Source.