Brochure

Liebert
®
STS2 Static Transfer Switch
The Liebert STS2 Static Transfer Switch provides an automatic, seamless
transfer between the outputs of two independent UPS systems and
the input of a critical load in a dual-bus power system. If the primary
UPS should fail, the switch will automatically transfer the loads to the
surviving UPS. For redundancy, the Liebert STS2 features three separate,
self-correcting logic modules. Each controller is capable of working
independently and each helps monitor the other two. Available in
capacities ranging from 100 up to 1000 amps.
True Front-Access Design
All mechanical and electronic components of the
Liebert STS2 are accessible from the front of the unit.
This gives you several immediate benefits:
Greater freedom in system design. The Liebert STS2 can be placed adjacent
to or in back of other equipment. It can also be placed against a wall or
partition.
Simplified installation, with ample space for cable connections through top
and bottom access plates.
Less floor space required for maintenance access.
Simplified maintenance, with all key components visible, serviceable and
removable from the front
of the unit, without the need to shut down the connected load.
Other Features Of The Liebert STS2:
Internal CANBUS protocol provides high-bandwidth communication
between system components via twisted-pair cables. Options can be added
as simple network nodes.
Internal dual-bus control power.
Simplified installation and maintenance.
Full range of communications options to fit any
monitoring strategy.
Three-pole switch configurations.
Optimized Transfer option uses the patented Liebert static transfer control
algorithm to eliminate downstream transformer inrush saturation. Meets
CBEMA and ITIC standard for critical loads.
True Internal Redundancy
The Liebert STS2 has triple-redundant logic. Each
DSP controller is capable of working independently,
and each helps monitor the other two. If one
malfunctions, the other two lock it out. Each
controller has power feeds from both power supplies.
The two power supplies feature true dual-bus power
distribution. Both have dual inputs, one from each
AC input source. All power connections have diode
protection, so that internal or external faults cannot
propagate. The result is a rugged, fault-resilient
package that is optimized for real-world applications.
Easy-To-Use Color
Touch-Screen Interface
The controls of the Liebert STS2 are
intuitive and simple. The pop-up menus
are easy to understand and provide a
wealth of operational and diagnostic
information.
The color LCD monitor is divided into
three segments. In addition to a system
mimic diagram, there is a status/
alarm panel and a section dedicated
to operator instructions and menus.
You benefit from improved operator
effectiveness, reduced training time,
and less chance of operator error.
The Key To High-Availability Power.
Power Distribution Systems
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