Eaton STS 2000A, Installation And Operation Manual

Page: 17 / 120

Eaton Static Transfer Switch 2000A 3-Pole Installation and Operation Manual 164001127—Rev 01 1
C Chhaapptteerr 11 S Syysstteem m D Deessccrriippttiioonn
This manual describes installation and operation of the Eaton PDI ® WaveStar ® Static Transfer Switch 2000
Amperes 3-Pole (STS 2000A). The Static Transfer Switch (STS) is a three-pole, two-position transfer device that
transparently transfers, automatically or manually, an output load between two three-phase input power
sources.
11..11 B Baassiicc C Chhaarraacctteerriissttiiccss
Purpose The purpose of the STS is to keep power supplied to a downstream mission-critical load by switching
between redundant power sources.
While a site UPS removes power anomalies originating between the power station and the site, the STS
mitigates the effects of anomalies between the Uninterruptible Power Supply (UPS), utility power source, or
other source and the STS load. These anomalies include:
• Loss of an upstream utility or UPS source
• Out of specification power from a power source
• Faulty transformers in PDUs
• Circuit breaker nuisance tripping
Transfer Switch The STS 2000A is a standalone transfer switch with two AC input sources and one AC output
load. The STS transparently transfers the output load automatically from one power source to the other, if the
active source fails or goes out of specification, or manually by operator directive, for testing or maintenance.
Static Transfer Switch Unlike electromechanical transfer switches, a static transfer switch has no moving
parts. It uses semiconductor technology, specifically silicon controlled rectifiers (SCRs), as power switching
elements, achieving faster transfers.
Sources The two input AC power sources should be independent power sources that are nominally of the
same voltage, phase rotation, and frequency. Inputs are usually from uninterruptible power supplies (UPSs),
but can be utility power sources, transformer outputs, or PDU outputs.
Output load The STS has a single AC output that supplies redundant power to downstream loads.
3-pole The STS switches a 3-phase AC load between the two AC sources. The neutral wire is not switched.
11..22 S Syysstteem m LLaayyoouutt
Figures Figure 1 , Figure 2 , and Figure 4 show the layout of the STS 2000A. Figure Figure 3 shows operator
interfaces. Figure Figure 5 has the 1-line electrical drawing.