Liebert SmartSwitchTM - Manual (Page 6)

2 Introduction
1.0 I
NTRODUCTION
The SmartSwitch™ is an automatic transfer switch designed to provide fast automatic transfers
between two independent, synchronous AC power sources to provide continuity of AC power to
critical equipment, such as information technology equipment, despite irregularities in either of
the two AC input power sources. The transfer is accomplished with sense and transfer times of
less than 6 milliseconds. The SmartSwitch is available in a 2, 3, or 4 pole configurations, with
ampacities of 13, 15, 20, 25, 30, 50, or 60 amps, in a floor, wall, or rack mount packages. Inputs
may be hardwired or plug connected to the two input branch circuits. Outputs may be receptacles
or hardwired connected to the load equipment.
The SmartSwitch consists of two modules, a fixed module containing the input and output connec-
tions and bypass switch with a compartment that holds the plug-in and removable electronics/
switching module. Figure 1 shows a typical one-line schematic diagram of the SmartSwitch.
Figure 1 Typical SmartSwitch One-Line Diagram
1.1 Specifications
1.1.1 General Specifications
• Manual and Automatic Transfers.
• Sense and Transfer Time: Less than 6 milliseconds.
• Break-Before-Make Switching.
• Selectable Preferred Source.
• Selectable Auto/Manual Retransfer.
• Retransfer Time Delay: 1 to 60 seconds adjustable.
• In-Phase Transfer Window: 1 to 20 degrees adjustable.
• Output Overload Transfer Inhibit: 1 to 10 times full load current adjustable.
• Programmable Switch Self Test.
• Convection Cooling.